Mar 162013
 
Earthquake danger zones in WA, OR, ID, MT.

Earthquake danger zones in WA, OR, ID, MT.

On Monday we quoted officials in Los Angeles who bravely told the truth and agreed it would be more than three days before any type of relief could be deployed to people after a major earthquake.

Their take – people should have enough on hand to be self-sufficient for at least two weeks.

On Friday a second story comes out, this time from Seattle, and with Oregon and San Francisco data also linked.  In a more detailed article and analysis, the Seattle Times looked at the likely consequences of a major but not improbably large earthquake occurring in the WA/OR region.

This chart, using information drawn from a Washington State Seismic Safety Committee report, shows the current shortfall between target recovery times and expected recovery times.

The complete 34 page report is available here and on its page 12 is the earthquake danger zone image we use above and an explanation of what it shows.

An earlier document here is also helpful in understanding weaknesses, vulnerabilities and dependencies.

Not Three Days.  And Not Two Weeks.  More Like Many Months.

We don’t know who started the ‘you should prepare for a three-day outage/disruption’ myth, and perhaps the originator’s intentions were good – on the basis that a three-day supply of life’s essentials are better than no supply at all.

But these reports abundantly show that after three days, there will still be next to no infrastructure or emergency support at all if the disruptive event is substantial in nature.

Furthermore, why do the quoted officials now talk about two weeks as the time period people should prepare for?  Their own studies show that two weeks is also a massively inadequate time frame.  Look at the data in their own reports (click the links above).

You can live without water for three days, but the target to restore water services is a week, and the current reality of when water supplies would be restored is an entire year.  Neither the target nor the reality seem close to acceptable, and clearly we must have our own water supplies.

One month for electricity, oil, gas, phone and internet service restoration – that’s the target.  The actual time to restore these services is currently projected at three months.  Okay, maybe you can live without the internet for three months, but without electricity or gas, and no oil products either (ie no petrol or diesel)?

Oregon data is not so clearly presented, but can be seen on the website of their Office of Emergency Management.  Kent Yu, who chaired their Oregon’s resilience planning, is quoted as saying that the current advice to stock up on enough water and food to last three days is laughable.  But his proposed alternative is only slightly less inappropriate, when he says ‘You need to prepare for at least two weeks’.  Clearly the emphasis in his statement needs to be on the modifying phrase ‘at least’.

The Seattle Times article lightly touches on the inter-connected nature of disaster recovery when it points out that if there’s no petrol and diesel, relief crews can’t get to where they need to go, and heavy machinery can’t operate.  But one wonders just how many inter-connected challenges will only be discovered after a disaster, and one wonders whether the current projected recovery times are realistic or wildly optimistic.

For example, the article correctly explains that replacement high voltage transformers would have to be built overseas and shipped here.  But the article says that this can take six months to a year – a statement that implies 6 – 12 months is an unusually long period of time.  In reality, most other analyses and real world experience points to lead times closer to 3 years from ordering to installing a new high voltage transformer.  And, for sure, if there were a sudden surge in demand for replacement transformers, no matter what the current lead times may be, the lead times for an unexpected sudden increase in demand would stretch way out.

Official Projections for San Francisco, Too

It is also interesting to view the seventh and eighth slides in this presentation that show the shortfall between targeted ideal response/recovery times and actual expected response times in San Francisco.  In particular, note how hospitals, which ideally would be disaster resistant, are expected to be out of service for up to 36 months, and emergency utilities, which ideally should be restored within four hours, are expected to be out for 60 days.  Utilities for non-emergency services, which should be restored within 72 hours, are expected to stay out for 60 days.

Also notable is the desire to allow 95% of citizens to be able to shelter in place in their homes within 24 hours of an emergency, but the reality suggests it could take up to 36 months for 95% of citizens to return to their homes (and longer for the unlucky remaining 5%).

A more detailed analysis on the sixth page of this presentation shows in San Francisco that the authorities actually project that only 85% of residents will be back in their homes within 36 months, leaving now 15% still homeless three years after the event.

So, what about public shelters?  The aim is to have them operating within 24 hours, the current reality is it might take four months to get them online.

So, here’s the question to ask your non-prepped friends.  If it takes three years or more to be able to return home, and four months before you can live in a public shelter, and 60 days before there’s any power or water, what are you going to do until then?

Summary

The Washington State Seismic Safety Committee has, as its objective, a 50 year plan to improve the state’s ability to respond to a major (but not improbable) earthquake.  Who knows how long it will actually take, and at present, it has not received any funding or support even to move forward on its 50 year plan.

So, for apparently the next 50 years or more in WA, the official state studies confirm what you already know.  You’ll be on your own for too long, and if you’re not prepared, your very survival is gravely at risk.

Similar studies in Oregon and San Francisco have similar findings.

We don’t know where the myth of ‘prepare for a three-day outage’ comes from, and even the new claim of two weeks seems wildly optimistic too.  These studies all convincingly point to best case scenarios of weeks, months, and in some cases years of outages.

Share this article and our earlier article with your non-prepper friends to show them it isn’t just you who advocates self-sufficiency.  The very people your non-prepper friends hope to save them are saying that they can’t do this.  It is up to us.

Mar 152013
 
The famous 'Wolf Map' purportedly shows the location of treasure buried by Jesse James.  You'll need location data for your buried cache, too.

The famous ‘Wolf Map’ purportedly shows the location of treasure buried by Jesse James. You’ll need location data for your buried cache, too.

Note this is the first part of a two-part article on how to record and locate a buried cache.  Please also visit the second part to complete your reading of this article.

There are many reasons to bury some of your prepper supplies, and to do so at a hidden location.

The main reason is usually not because you have something illegal you want to hide.  The main reason is more likely to be because you want to protect your supplies from an uncertain future, and most of all, from people seeking to steal your supplies from you – either by theft/burglary while you’re away from your store, or by violence/force while you are present.

A buried cache is probably the most resilient form of storage there is.  It is (relatively) safe from man-made threats and also from natural threats such as hurricanes, tornadoes, and fire.  It is a constant temperature cool environment.  Obviously flooding is a threat, but equally obviously you shouldn’t have your retreat location in a flood plain to start with, and as long as your cache is waterproofed (which it should be, no matter if there’s a flooding risk or not) then some surface water above it for a while shouldn’t be a problem anyway.

The process of preparing items for burial, what to bury them in, and so on are all subjects for other articles at other times; our focus today is on a very important aspect of the complete process – being able to find them again.

Depending on where you locate it, finding your hidden buried cache may not be as easy as you hope and assume it is, and so you should carefully consider where to bury your cache, and what to use to help you locate it again.

On the other hand, if you make your cache location too obvious, then you run the risk of having other people find it, too.  It is entirely possible that if people think you may have a cache, then in the future they might go looking for it with the aid of a metal detector.  But while they’ll look for it close to your retreat and close to other objects, they’ll probably not painstakingly search through every square foot of all the acres you own, so it behooves you to avoid some of the easiest cache locations, because they are probably also the most obvious.

The few minutes it takes you to read this two-part article now, and the extra time it takes you to apply the ideas and concepts we explain, may be time extremely well spent.

The main things to consider are your choice of reference points, how you describe your cache location with relation to your reference points, and how many reference points you specify.

Using Multiple Reference Points/Bearings

We urge you to use multiple points of reference that you work from to calculate your cache location, either in terms of distances and/or angles/bearings, for three reasons.

First, the tools you use to identify your cache may not be available to you at an unknown uncertain future time.  For example, if your references are all compass bearings, maybe you don’t have a compass with you when you need to dig up your cache.  If your references are all distances from known points, maybe you don’t have a measuring tape with you.  And so on.

Second, some of the reference points you are using to locate your cache may disappear or change.  It is highly possible that fence posts might fall over, trees might be cut down, and so on.  Or maybe a reference point simply gets obscured by something else being built (or naturally growing) in front of it.  It you can’t see your reference point, then that becomes essentially the same as it no longer being there if you are using visual bearings.  If you are using distances, if something is built in front of your reference point, it becomes much harder to calculate the straight line distance when your measuring now has to do a loop around the obstacle.

Third, the more bearings or measurements you have, the more accurate your location fix becomes.  Maybe the first set of two bearings ends up giving you an oval area perhaps plus or minus ten feet on one axis and five feet on the other axis – that gives you 160 sq ft of space within which you’ll hopefully find your cache, and depending on what you’re using as a reference point, this is close to a best case scenario.

If you add another bearing, maybe that gives you a 4′ radius circle instead, – about 50 sq ft of space in which to find your cache.  That’s a huge improvement.

A fourth and subsequent bearing (or measurement) won’t necessarily reduce that area much – perhaps it might make it a 3′ radius circle (ie about 30 sq ft), but it gives you backups in case of problems with some of the other reference points.

The Closer Your Reference Points, the Better

Your reference points will give you a much more accurate ‘fix’ on your cache location if they are close to it.  For example, if one reference point is ‘The cache is six feet west of this fencepost’ then how hard is it to miss the cache?  You know you can measure six feet to within a few inches, and even if your measurement of what is west is off by an enormous 30 degrees, that only shifts your measurement by 3½ feet.

On the other hand, if you are measuring from the barn in the distance – let’s say it is 500 yards away – then if you have a 1% error in your distance measurement, that adds 15 ft of error.  In addition to the distance measurement, your bearing might be off too.  Lets be kind and say that you are not off by a huge 30°, but by only a tiny 3°, but that adds 78 ft of uncertainty. giving you now a zone 15′ long and 78′ wide – a huge 1170 sq ft within which your cache might be located.

As for a bearing to the mountain peak 10 miles away, even if you were to measure the bearing to it to an extraordinary 1° of accuracy, that still gives you 950 ft of uncertainty, which is close to useless.

Far away bearings can be okay to help you locate the general area, such as which field out of a dozen fields your cache is within, but you need your ‘real’ reference points to the cache to be as close as is possible in order to secure the most accurate fix on your cache.

Choosing Your Reference Points

Of course, you need to describe your cache location in terms of where it is related to a number of reference points around it.

The first thing to appreciate is that you want to have multiple reference points (see above) and they should be spread more or less around on all sides of the cache location if at all possible.

Ideally if you have only two reference points (which is not ideal) they should be at right angles to each other, when viewed from the cache.

If you have more than two, try to get some on the opposite side of the cache to the others.

Your reference points should be things you can readily find at any time of year, and ideally that you can see from your cache.

Your reference points should be as permanent as possible, and least likely to change or become unclear or obscured in the future.

Some things are vulnerable to changing over time.  For example ‘the highest tree, which is near the middle of that row of trees to the south’ – what happens if one of the trees next to it grows higher?  Or if the highest tree dies and falls down?

Even buildings are impermanent.  They may get pulled down, or they might get altered (so, eg, a reference point like a high point on the roof line or a corner of the building changes), or other buildings might be added in front, obscuring the reference building and making distance measurements now difficult.

If there are nearby official survey pegs and/or memorial markers, these are excellent objects to work from.  They probably look inconspicuous (make sure you can be sure of always finding them!) and are normal things to find on any property.

If you are in an area with utilities, then things like fire hydrants, power pylons or lampposts, manholes, and utility boxes can also provide semi-stable reference points.

There’s no reason why you can’t create your own markers to make things very much simpler.  Maybe you build a pig sty or a cattle water trough close to your cache and use that as a marker.  Maybe you run a fence line or dig a ditch or make some other sort of appropriate landscaping change.  Maybe you have a compost bin or a trash incinerator.

Angles, Bearings, and Distances

There are many different trigonometric techniques you can use to locate your cache with reference to external markers.  Essentially, they fall into three groupings – angles relative from something to your cache, bearings from a compass, or distances from a point.

While there are reasons to like bearings (ie as taken by a magnetic compass) we prefer using angles with respect to other objects if possible.  The reason for this is due to the earth’s magnetic north moving.  In the American redoubt area, every six or so years, magnetic north has shifted, with respect to true north, by a degree (note that this rate of change may speed up or slow down in the future and possibly even reverse).  There are also some people who theorize that the earth’s magnetic field may be due to flip over entirely in the foreseeable future; and if such an act were to occur, not only would you for sure be forced to your retreat and need to access your cached supplies, but magnetic bearings would become totally invalidated.

On the other hand, being able to say ‘follow a line that goes 25 degrees to the north of the heading from here to that other place’ is a relatively fixed reference that does not rely on a slightly unreliable magnetic north.

Of the three techniques, the best to use are measured distances.  These are much more exact than angles and bearings.  When specifying a distance, you generally give the magnetic bearing the distance should be measured from the reference point to the cache, this does not need to be quite so exact.

If you inscribe a partial arc on the ground at the measured distance from the reference point, with the arc swinging around even 30 degrees relative to the approximate line of travel, this is fine because your second measurement from another point will then intersect with the arc at only one or two points.  Add a third measurement and arc, and you now are starting to create a ‘hot zone’, and more or less in the middle of that hot zone is where your cache should be.

You can also use a concept of ‘run a line between this object and that object.  The cache is located at a point x feet from the first object on that line.’  Or, ‘run a line between this object and that object.  At a point x feet from the first object, now measure another y feet at an angle of z degrees from the line to reach the cache’.

There’s another form of reference you can use as well.  Boats will use sets of markers ashore and line them up, one behind the other, to allow them to know exactly where they are at sea.  You can use the same sort of technique – if it is possible to take advantage of, or to create, two objects that are lined up so they are (inconspicuously!) pointing to your cache, that is an obvious easy visual aid as well.

Read On for Part Two

Note this is the first part of a two-part article on how to record and locate a buried cache.  Please also visit the second part to complete your reading of this article.

Mar 152013
 
Some type of a diagram of how to find your cache from reference points will help you make sense of your notes.

Some type of diagram showing how to find your cache from reference points will help you make sense of your notes.

Note this is the second part of a two-part article on how to record and locate a buried cache.  Please also visit the first part to complete your reading of this article.

Recording Your Reference Points

In general, there is less possibility of mistake if you express each marker both in terms of how it is calculated from the marker to the cache, and from the cache to the marker.

To start with, when you have no idea where your cache is located, you’ll want to first go to known markers and use the information expressed in terms of how to find the cache from the marker.  After using one or two of these, you’ll end up with a likely location for your cache, and you can then fine tune the calculation from the cache using the directions from the cache.

Depending on the time of instructions, it is usually easy to express them in either direction.  A distance remains the same, no matter which end you’re measuring from, of course.  A bearing from a marker to your cache becomes the bearing from your cache to the marker by simply adding (or subtracting, whichever is easier for you) 180 degrees.  For example, a 50 degree angle from the marker to the cache becomes a 230 degree angle from the cache to the marker.

Some things won’t be so readily measured both ways.  If you’re using a relatively distant point (a bad thing to do, as discussed above) then you probably will only use the direction from the cache to the distant marker, so as to cut down on the travel.

There’s another aid to assist you in locating your cache as well.  You can take photos – both of the cache site from nearby points, and of the views you see from the cache site.

If you take pictures, don’t just leave them on a memory card.  Print them out.  That way you are protected in case your memory card fails, or the system you’d use to read the pictures off the card fails.

It is very helpful if you can also make up a diagram showing the angles, bearings, distances, reference points, and everything and how all the different parts line up and result in locating your cache.

How Do You Orient Your Cache to your Ground Zero Point?

You also need to plot how your cache lies in the ground so you know the overlap between where your cache actually is, beneath you, and the invisible ‘X marks the spot’ point above it that your calculations are hopefully directing you to.

If the first trial dig down to where you think the cache might be doesn’t locate it, are you best to now widen your hole to the north, south, east or west of that first point?

Our slight preference is to use more or less the center of the cache location as your reference point, but do whatever works best for you.

How to Measure Distances

This might seem simple, but the chances are that the distances you want to measure will be more than ten or twenty feet, so your choice of measuring tool starts to have an impact on the accuracy of your measurement.

On the other hand, if you have some flexibility in choosing your cache location, maybe it is prudent to locate it closer to a reference point, making it easier to return to in the future.

For longer distances, a laser rangefinder can be a great convenience, although it is obviously a high-tech product that you can not guarantee to be reliably available and functional in a future scenario.  We discuss laser rangefinders and other high-tech aids to locating caches in a separate article.

The best low-tech method of measuring longer distances is usually with a long measuring tape.  You should buy a couple of long measuring tapes – Amazon has a 400 ft tape and a 300 ft tape on convenient spools, for example – this link takes you to a selection of long tapes they offer.  These are much easier to use than a shorter tape that you have to keep ‘flipping over’ or ‘leapfrogging’ and reusing, and this makes them more accurate too.

You might want to consider buying two tapes.  That way, when figuring out your cache location, you can stretch both tapes out from different reference points simultaneously to see where they meet up.  Oh – don’t forget that with two reference points, there will be two points where the distances meet up, and sometimes a long way apart.  You need a third reference point and measurement, or accurate bearings to/from the two reference points, so as to know which of the two reference points is the correct one.

When you’ve measured out the distance from the reference point to where your cache should be located, be sure to pull the tape reasonably tight (not so tight as to stretch it, but tight enough to ensure the tape is in a direct line).  This will straighten the tape and give you a more exact measurement.

There are also measuring wheels available, but we don’t like these quite as much as tapes.  There are two possible errors introduced with a wheel that are not as prominent with a tape.

The first is that on uneven ground, the wheel may not read quite as accurately as on even ground.  This error can be minimized by using a larger diameter wheel – use a 12″ instead of a 4″ wheel, for example.

The other problem is that you need to move the wheel in a direct and straight line from the reference point to the measured distance.  If you weave about a bit rather than proceeding directly straight, then this will introduce some error, too.

These errors can be quite small, however, and you could also help minimize the error by measuring each distance twice and averaging the results.  Indeed, if the difference in measurement was significant, measure three or four times.

Identifying Cache Locations in a Forest

Much of our discussion to date has assumed that everything is in nice easy unobstructed straight lines from each other, such as in an open field.  But maybe you are instead hiding a cache somewhere in a forest.  All you can see around the cache are trees, and they all sort of look the same.

That is very much more difficult a scenario to work from, and is made harder by the fact that most forests have trees falling down from time to time such as to distort your perceptions of locations, tree counts, and so on.

There are various ways you can ‘signpost’ your way through a forest.  If there’s a clearly established trail, then that should be your reference point, and we’d probably then choose to use a wheel type distance measuring device.

We would segment the trail into lengths, each of which had a clearly recognizable tree or stump or other feature at the start/end of it.  The directions might be something like this

  • Proceed about 150 ft until finding two large trees on the right and no trees for at least 10 ft on the left of the trail.
  • From the further away of the two trees, now proceed another about 200 ft until you come to a fallen over tree parallel to the trail on the left.
  • From the base of the fallen over tree, proceed another about 180 ft until coming to a point where two trees on the right line up, one in front of the other, at a 30 degree angle.
  • At this point, head off the trail on a 75 degree angle until …..

Sure, you could simply say ‘Go 530 ft along the trail until reaching two trees lined up at a 30 degree angle’ but by splitting the path into segments, you give yourself recalibration points, and furthermore, if one of the points disappears, you still have other points to guide you.  Maybe the fallen over tree has been cut up and hauled away for firewood.  If you can’t find it, you instead know to proceed 380 ft from the two large trees on the right.

In addition, we don’t much like following trails, because other people follow trails too.  Trails are also not fixed.  They can disappear if they are not regularly used, or one lightly used trail can be superseded by a slight change in usage – a downed tree further along the trail might redirect people a new way, and so your trail now follows a different path.  In winter, snow can obscure the traces of any trails.

Probably the key consideration here is that if you’re going to hide a cache in a forest, it is best to hide it not too far into the forest, or, if further in to the forest, not too far from an obvious impossible to miss reference point.

Another technique you can use in a forest is to consider marking your trail by way of subtle signs on trees.  What is the most subtle sort of marking?  Hammer a nail or two into the tree at a specific height (say 3′ or so above the ground) and perhaps on the north side of the tree.

The nail will quickly disappear into the tree bark, but if you then go searching it out with a hand-held metal detector, it should be easy to spot if you know to focus on the north side of trees about 3′ from the ground.  Then plot a chart showing the ‘chain’ of marked trees, with bearings/distances from each to the next, and follow the ‘hidden’ trail you’ve created.

Hiding Your Instructions

Do we need to point out that you don’t want to print out your cache location data in large bold type and stick it with a magnet to your fridge door?

The first thing you want to do is keep all knowledge of you having a cache as tightly restricted as possible.  If people don’t think you have a cache, they’re less likely to search for either the cache itself or for directions to it, and they’re less likely to recognize your directions, if they should stumble across them, as being related to finding your cache.

You do need to have your instructions written down.  You can’t trust electronic devices to remain operable in the future, so you need a good old-fashioned written in ink on paper set of instructions.  We’d also recommend having multiple copies of the instructions, so if one copy gets lost or damaged, you still have others you can use.

You can secure your instructions several different ways.  You should adopt several of these strategies.  But make sure that whatever you do and however you do it, you are then sure to remember the details, so in the future you know where to find your directions and how to decode them.

  • Hide them somewhere really secure and secret and safe.
  • Write them in invisible ink so people see a ‘normal’ piece of paper somewhere in a normal (not hidden) place and think nothing of it.
  • Alter the instructions – perhaps add 5 to everything.  A 15 yard distance becomes 20 yards.  A 35 ft distance becomes 40 ft.  A 35 degree bearing becomes 40 degrees.  The 2nd tree on the left becomes the 7th tree on the left.  If there are some numbers you can’t change because they’d then look ridiculous, use a special code marker to indicate that it is a real number rather than a changed number.  Perhaps spell the number rather than write it in numerals, or have a word like ‘about’ as an indicator that the number following has not been altered.
  • Transpose digits.  Swap the ones and tens digits on any numbers.  If the number is 13, it becomes 31.  If the number is 2076, it becomes 2067.  And if you have single digit numbers, think of them as, eg, 03, so swapping that becomes 30.
  • Make notes on pages of a book on your bookshelf, with perhaps only the notes on pages where the page number is divisible by three being valid notes.  Hopefully people won’t go thumbing through the book to start with, and if they do, they won’t know what is what.
  • Split the instructions up and keep half somewhere and the other half somewhere else.
  • Hide them ‘in plain sight’ in a pile of other junk and papers.
  • Write them in code so they appear meaningless.  For example, use A, B, C, D instead of NSWE, use F for feet, I for inches, and Y for yards.  Maybe E for degrees, and X for ‘looking from the cache to the marker’ and Y for ‘looking from the marker to the cache’.  So you could encode the instruction ‘the cache can be found by following a line at an angle of 15 degrees for 50 ft from the gatepost as 15E50FYgatepost.  If this was all in a notebook with lots of other semi-random jottings and notes, they’d not stand out as directions to a cache.
  • If you have photos identifying your cache, or from your cache, maybe have a family member posing at the cache point (if a photo to the cache) or in the foreground (if a photo from the cache) so as to make the photo seem like a typical family photo rather than a cache location photo.
  • A bothersome but ultra-secure strategy is to have your directions leading to a ‘sacrificial’ cache, and your main cache being a secret distance and direction from your sacrificial cache.  This can help you two ways.  If someone finds the cache map, then when they find your cache they’ll stop looking for more caches.  Secondly, if you find yourself forced to reveal your cache, you can show them the map to your sacrificial cache and not need to disclose the second more substantial cache.  Make sure the main cache is far enough from the sacrificial cache so as not to be accidentally found when people are searching for the sacrificial cache!

If possible, have the instructions typed/printed out rather than handwritten.  If someone finds them and demands that you interpret them and lead them to the cache, you can say ‘Joe did that, and he isn’t here, so I’ll try to help you, but only Joe knows exactly what he means’.

That way, when the instructions don’t work, they’re not going to pressure you to tell the truth, because you’ve already said that the instructions are Joe’s, and relate to his cache.  You don’t know what is in the cache, where it is, or how to read/decode Joe’s instructions – clearly Joe didn’t trust you or anyone else with that information.  They are not in your handwriting, so it is hard to be contradicted on that point.

Note this is the second part of a two-part article on how to record and locate a buried cache.  Please also visit the first part to complete your reading of this article.

Mar 122013
 
A typical medium quality sighting compass.

A typical medium quality sighting compass.

This is the first part of a two-part article on choosing/buying a compass, the second part talks about compass features, and we’d recommend you read it after this first part so as to have a more complete understanding of what to look for when selecting a compass.

These days compasses seem very old-fashioned.  If people wish to know which way is north, they can look at their GPS; and if they have a compass at all, it is as likely to be a digital compass as a traditional magnetic compass.

Indeed, the prevalence of GPS units has made the underlying entire skillset of map reading and direction finding, and the need to even know where north is, apparently obsolete.  You just enter a location into your GPS then follow its arrow to get there.  You no longer need to know where you are, or even where your objective is, or what heading to travel along.  All that matters is to follow the arrow.  Even better still, if you have to make a detour due to some obstacle along the way, the arrow is continually updating and recalculating, always pointing you the most direct way to your objective.

The Problems with Modern Digital Navigation Devices

But, as wonderful as they are, it is not prudent to rely on modern high-tech devices when planning for a future Level 2 or 3 scenario.  It is very likely, in such cases, that the GPS service will be degraded or fail entirely.  In addition, sooner or later, the electronics inside your high-tech devices will fail, either a ‘natural/normal’ failure or one perhaps induced by an EMP event; and whatever the cause, you probably don’t have the knowledge – or the spare parts – to repair them when they fail.  Maybe it will be something else equally inevitable – at some point, you’ll simply run out of batteries.

While modern high-tech devices are subject to all these possible failure conditions, a regular ‘old fashioned’ analog compass is a gloriously low-tech device that is very hard to break, and moderately easy to repair.  By all means have a selection of high-tech navigation aids, but ensure you have some compasses too to get you as close as possible to guaranteed availability of navigational aids in the future.

Note also that neither GPS units nor digital compasses are very accurate.  Our sense is that digital compasses are generally accurate to about 5 degrees at best, and may be much less accurate than that.  Never mind that it displays a nice exact seeming number of degrees, the underlying sensor is not all that accurate.

GPS units can only show heading data based on the change in location between now and their previous location reading, which, particularly if you are walking or moving at slow speed in a vehicle, embodies errors to do with both the location fixes, and if the distance between the two fixes is small, then the accuracies become a large percentage.  As you hopefully already know/realize, when you are stationary, a GPS has no idea which way is north.

Different Requirements Call for Different Compass Capabilities

There are two main purposes for a compass.  The first is obvious – for finding your way to your objective when traveling somewhere.  The second use you may have for a compass is to assist when locating an object – possibly yourself, or possibly something else.

These two purposes place different demands on a compass, and – perhaps surprisingly – in most cases a navigational compass need not be as accurate as a locator type compass – particularly when it is used in conjunction with a detailed map of the area you are traveling through.  Indeed, compasses and maps are almost inseparable partners, with both being much more useful when used together with the other.

That’s not to say that more accuracy is ever a bad thing, but more accuracy usually is associated with more cost, and an outdoor hiking/backpacking type application for a compass can sometimes result in compass damage or loss (ie by dropping it), so it can make sense, depending on the nature of your travels to sometimes leave the ‘best’ compass at home and stick to using an expendable type compass for outdoor navigation.

Compass Types

There are two main types of compass.  They both have a needle, and both point to magnetic north.

The major difference between them is how you can use them ‘in the field’.

baseplatecompassbBase Plate Compasses

‘Base plate’ type compasses are designed to be best used on a map.  They are flat, with the compass itself usually set into a rectangle with some straight edges and lines which you use to align to the relevant parts of your map.  This rectangle is the ‘base plate’ implied by the name of the compass type.

There might be scales on the edges to help in map reading, and often the rectangle shape is made out of clear plastic so you can see to the map underneath.

This illustration of a K & R Baseplate Compass shows how a typical baseplate compass is designed.

The base plate compass is good for using with a map and working on bearings and headings.  But how do you then take that information and use it to work out where to travel, ‘in the field’?  That’s where the second type of compass comes into its own.

compass_sightingbPrismatic and Lensatic Sighting Compasses

These types of compasses have an arrangement whereby you can simultaneously see a compass reading on the compass and also line it up with an object around you.  You sight the compass on an object – maybe a mountain peak, a tree, whatever; and then, without moving yourself or the compass, read the bearing to it from the compass card.

Alternatively, if you know you should proceed in a certain direction, you can line your compass up to that direction, then look through the external sighting slot and choose a distant object to proceed towards that will mark your appropriate direction of travel.

The illustration here gives an example of a Cammenga Model 27CS Olive Drab Lensatic Compass and shows how it can be used to simultaneously display the compass reading and align it to an external object.

These compasses are excellent for fieldwork, but not so good to use on a map.

 

hybridcompassbHybrid Compasses

Increasingly, there are good compasses now being sold that can work both on a map and in the field, and for most people, this ‘one size fits all’ design approach makes them a good choice.

The illustration shows a high quality Suunto brand hybrid compass.

Compass Accuracy

The concept of accuracy is often misunderstood.

For example, in this compass listing, which is the most popular prismatic compass on Amazon, note one of the first reviews (giving the $10 compass an improbable full five stars) which says

If you are looking for a direct sighting compass with 1 degree (or better) accuracy, that is quick to use and virtually foolproof, this is the bargain of the decade.

Currently, 245 out of 250 people found the review helpful.  We are not among them.

The review’s claim that the compass has a 1° or better accuracy is total nonsense.  The compass scale is only marked in 5° increments, so there’s no way it could be five times (or more!) accurate than its own scale.

There are at least four sources of error in reading a compass, and two of those four are independent of the compass itself.

Error 1 – Mechanical

The first compass source of error is mechanical.  Maybe the needle sticks a bit – chances are you can move the compass very slightly and the needle will follow, it likely needs some force to dislodge it from where it had settled, and maybe it then sticks again before settling at the exact new point.

Maybe the needle is not perfectly balanced (indeed, it is probably deliberately not perfectly balanced) and you’re not holding the compass perfectly level, so that makes the heavier end want to drift downwards and scrapes along the bottom of the compass card, or points upwards and scrapes along the top of the viewing glass.

Maybe the outside bezel has a bit of slop in it relative to its position to the internal markings.  Maybe the sighting posts also have a bit of wobble or have been slightly bent.

All these issues can add to the mechanical lack of precision inherent in a compass.

Error 2 – Precision

The second source of compass error is the precision with which the scale is marked and aligned with the compass needle.  Maybe when the markings on the compass card were printed the printing wasn’t exactly aligned.  Maybe then the needle isn’t exactly centered in the card.  Maybe you’re looking at it on an angle too, introducing further error.

Even with these possible error sources minimized, the best case accuracy is probably no more than half of one marking unit.  If the compass is marked in ten degree units, maybe you can guess when the needle is halfway and fairly say ‘this is probably about 5 degrees because it is sort of in the middle’ but you know that there’s no way, with only ten degree markings, you could claim with any confidence a degree measurement to within 2 or even 3 degrees, based on the scale errors alone.

Error 3 – Magnetic Interference

Now for the two major external sources of errors reading a compass.  The first of these is the possible presence of stray magnetic fields or metal that might bias the compass reading.

What’s that in your pocket – your cell phone?  And on your hip – your pistol?  Both of those will impact on the accuracy of your compass reading, as will other metal objects or magnetic fields nearby.

Error 4 – User Errors

The second source of external error is – let’s be as polite about this as we can – you.  The person using the compass.  Maybe you’re not aligning the compass exactly with whatever bearing point you are taking a bearing from/to.  Maybe you didn’t wait for the compass needle to fully settle.  Maybe you just misread the number on the compass card.  Human error is always potentially present.

So how accurate is your compass?  As you can see from the four sources of errors discussed above, that really depends on how skillfully you are using it, and how careful you are to search out and eliminate some of the possible error sources.

We use a rule of thumb that whatever resolution is shown on an instrument’s scale is probably indicative of what the instrument’s capabilities are.  This rule of thumb is sometimes invalidated with digital devices, where it is inexpensive and simple to add extra digits to the digital display, to imply an accuracy that is completely absent.  But for analog compasses, it is probably an acceptable rule of thumb to say that most of the time, whatever the resolution on the compass card is will be about the same as the best resolution you can hope to achieve in the field.

So the highly rated compass with the claimed 1° of accuracy we started off by citing?  With 5° markings, the best you could hope for in a perfect world is 2.5°, and probably, in real life, after allowing for the other three types of errors above, you should consider it to be accurate to about 5°.  That’s a great deal less accurate than incorrectly claimed in the review.

Summary

Good quality compasses can give high quality results.  We’d think that obvious, but the $10 compass that was given a five star review and claimed to be five times more accurate than it truly is, and which received 245 approving responses out of 250 total, suggests that we should revisit the obvious.  🙂

When buying  a compass to help you locate yourself or other objects (ie ‘surveying’ type applications), you should choose one with the most accuracy.  This is implied by its marking resolution, and further implied by the size of the compass card (ie the diameter of the compass mechanism), and by it being (or not being) a recognized valued brand name and at variously a high or low price.  Yes, you generally get what you pay for, with compasses as with everything else.

But if you are simply seeking to navigate from Point A to Point B, and with a map as well as a compass, a less accurate instrument is fine.

This is the first of a two-part series on buying compasses.  Please visit the second part for a discussion on specific compass features.

Mar 122013
 
Brunton make high quality compasses, such as this very fully featured Pocket Transit.

Brunton make high quality compasses, such as this very fully featured Pocket Transit.

This is the second part of a two-part series and you should read both parts for a more complete understanding of issues to do with choosing/buying a compass.

In the first part of this Buyer’s Guide to Compasses we discuss the two or three basic design styles/types of compasses, and issues associated with the accuracy you can realistically expect from a compass.

In addition to these different types of compasses, there are a number of features that may be present in various forms or absent entirely on each particular model of compass.

We discuss the most obvious of these below.

Compass Size

The larger the circumference of the compass card, the greater the distance between the degree markers and the more accurately you can use the compass.  There’s not a lot of variation in compass size, but where there is a difference, the bigger it is, the better it is.

Compass Build Quality

This is a slightly subjective feature, and hard to evaluate on a brand new compass.  But a better made compass will stay more accurate for longer, and won’t have parts come loose and start to wobble and wiggle.  Any movements in any of the parts that are used to align the compass will of course detract from the compass’ ongoing accuracy.

A better built compass will also be more robust and resilient such that you can occasionally drop it or otherwise treat it in a less than perfect manner, and still function.

A better built compass will also be operable over a broader range of temperatures.  Particularly if the compass is liquid filled, there will be a temperature at which the liquid will freeze, and somewhere above that temperature is the lowest temperature the compass will work happily at.

Adjustable Declination

Compasses point (sort of) to the magnetic north pole.  Unfortunately, this is not the same location as the north pole used by map makers and which most grid reference systems are based upon.

We’ll spare you the geometry of it, but the net result is that to switch from your compass’ reading of magnetic north to true north, you need to add or subtract an adjustment to compensate for the difference between the magnetic and true pole.  This adjustment is termed the declination.

Compensating for declination is, on the face of it easy, but few things in life are truly easy, and there are three things to consider.  The first thing, which confuses many inexperienced navigators, is that sometimes you have to add and sometimes you have to subtract the declination from the magnetic (or true) degrees indicated.  Knowing when to add or subtract can be quite taxing of your brain, particularly in a high stress environment (which reminds us of the really big problem some people have with compasses – mistaking the north and south ends of the needle!).

The second challenge with declination is that it is not the same everywhere.  It changes as you move around.  For example, at present, in Coeur d’Alene, ID, the declination is +15°1′.  Go east to Billings, MT, and the declination is +11°11′.  Go southeast to Cheyenne, WY and the declination now is +8°44′.

That’s a lot of change in not much area.  You can ignore declination changes over short distances (for example, the 140 miles, as the crow flies, between Coeur d’Alene and Missoula, MT has the declination change from +15°1′ to +13°52′ – a change of a relatively minor 1°9′.  And the further south you get, the less the rate of declination change.

The third challenge is that the magnetic north pole is moving.  It isn’t fixed.  It is moving – and at an accelerating rate, currently of about 25 miles a year.  In the American Redoubt region, that translates to a reduction of declination by about 9 minutes every year at present.

Anyway, now that you know more than you ever want to know about declination, back to the simple point.  Some compasses allow you to automatically build in a correcting factor for declination.  This is a very valuable feature, and saves you needing to struggle to remember if you should be adding or subtracting at any given time and situation.

Scales – Degrees and/or Mils

You probably already know that there are 360 degrees in a circle.  Most compasses are calibrated in degrees accordingly, with 0° (or 360°) being at the ‘top’ for North, and so on.

There are other scales for angular measurement as well as degrees, however.  There is a metric measurement, the ‘grad’ which is happily almost never used (there are 400 grads in a circle – about as stupid a number as 360, really).  But the one you are more likely to come across is the ‘mil’.  This is a subdivision of a radian (there are 2π radians in a circle – about 6.283, a number which seems awkward, but which has some benefits in geometry).  There are 1000 mils in a radian, or 6283 mils in a circle.

Just to make this simultaneously simpler and more complicated, the 6283 mils are often rounded up to 6400 (why not 6300?) in this country, but in some other countries, may be rounded down to 6000.

There are 17.8 mils in one degree.

The use of the mil measurement has one useful feature – it helps you when estimating distances or sizes.  If you know the size of something, you can tell its distance by the number of mils in size it appears to be.  Or if you know the distance to something, you can tell its size the same way.

The way it works is that if an object is x mils wide, and 1,000 units of distance away from you, then that object is actually x units distance wide.  For example, a 2 mil wide object that is 1500 yards away would be 2 x (1500/1000) yard wide – in this example, 3 yards wide.

You can also use this for estimating distances.  For example, if you say that a typical man is 6′ tall, then if he is filling 12 mils, he would be 500 feet away.  If 6 mils, he’d be 1,000 ft, and if 3 mils, he’d be 2,000 ft away.  That’s why many rifle scopes have mil markings on them.

Or if you saw two mountain peaks in the distance and wondered how far away they were, and your map showed them to be 1 mile apart, and they registered as 100 mils apart on your compass, that would tell you they were 10 miles away.

A compass with both mil and degree markings is perhaps slightly better than one with only degrees, but unless you have a use for the mil calibration, your first priority should be to get the best possible compass with degree markings.

In addition to working out distance/size from mil angles, some compasses also have quick tables of degree angles subtended vs distance/size that you can use as rules of thumb, conveniently printed on them.

Luminous Markings

There are plenty of situations where you might be using your compass in low/no light conditions, and if the compass had either a tritium self-illuminated dial or a phosphor coating that would ‘soak up’ some light, eg from a flashlight, then give it off again for some minutes or longer, that might be very helpful.

A phosphor coating of course requires you to have some other light-source to activate it, although it is probably reasonable to assume that you would indeed have a flashlight with you.

The tritium coated compasses are nice, but tritium has ‘only’ an 11 year half-life.  In other words, in a decade, it will only be glowing half as bright as when you bought it; in two decades, one quarter as bright; and in three decades, one eighth as bright.

We’re not saying you must get some type of self-illuminated markings on your compass, but if the price isn’t much more, it might be nice to have them.

Liquid-Filled Compass

Better compasses have some type of liquid in the compass housing.  This damps the needle’s movement and protects it some from shock as well.  If you are looking at a compass that is not liquid filled, you are probably not looking at a good quality compass.

Level Bubble

In most cases, the more level your compass, the more accurate your reading will be.  Accordingly, some compasses have a bubble level somewhere that allows you to check how level your compass is.  This might be in the form of a bubble in the liquid that fills the compass housing (assuming the top of the housing is then slightly curved) or it might be a separate liquid bubble level to one side.

Clearly, this is a good extra feature to have.

Global Needles

The needle in your compass ideally wants to point more or less directly to the magnetic north pole, following the line of force that flows between the earth’s north and south magnetic poles.  Near the equator, those force lines are pretty much parallel to the earth’s surface, but as you get closer to the magnetic pole, the force lines are curving inwards and downwards (or outwards and upwards) and so the needle wants to go off-center, off-balance.

This would interfere with its free swinging on its mounting point, and so compass needles are typically made unbalanced, with a compensating weight on one side or the other of the needle’s center, so as to adjust for the magnetic force lines wanting to force the needle up or down.

This means that a compass made for eg North America would not work so well in eg South America, because the balance correction swaps.

Some compasses have a clever mounting mechanism for the magnet separate from the indicating needle which makes it less sensitive to the shift in direction of the lines of magnetic force.  This is useful not only for the international traveler, but also for everyone, everywhere, because a related benefit is that the compass doesn’t need to be held quite so exactly level in order for an accurate reading to be obtained.

Summary

Of course, these features all have costs associated with them, and remember from the first part of this compass buying guide, compasses don’t always need to be ultra precise.

The more accurate that compasses are, the better they will assist you with tasks such as locating a buried cache on your property or surveying work in general, but even a much less accurate compass can help keep you situationally aware when traveling through unfamiliar territory.

We find that Amazon has a good range of well priced compasses available.  There are also specialty compass stores online, and your favorite outdoor retail store probably has a range of compasses that you can actually hold and physically choose from too.

Please note this is the second part of a two-part article about choosing a compass.  Please also visit the first part to understand about the two major types of compass design and issues to do with compass accuracy.

Mar 112013
 
Simultaneous fire and flood after Japan's March 2011 earthquake.

Simultaneous fire and flood after Japan’s March 2011 earthquake.

Even though it is we who should be making fun of them (and of course we don’t – at least not to their faces), non-preppers like to poke fun at us, and to suggest that we’re in some way foolish, maybe paranoid, and definitely being unnecessarily worried about things we have no reason to worry about.

Unspoken in their thoughts is always the concept that if prepping were prudent, surely the government would either do it for us, or encourage us to do it ourselves.

The curious thing about this perception is that – if they only cared to look and listen – they’d see plenty of examples of government departments at city, county, state and federal levels all encouraging us to become semi-self-sufficient for varying amounts of time.

Here’s the most recent example.

Los Angeles held a memorial ceremony today to commemorate the second anniversary of the March 2011 earthquake in Japan, an event that killed 18,000 and destroyed 300,000 homes, to say nothing of the consequential tsunami which damaged three nuclear reactors and caused the second worst ever release of radiation as a result (only Chernobyl was worse), with fallout spreading even to the US (and causing a panic rush on Potassium Iodide supplies to the point where individual tablets started selling for more than entire bottles previously did).

Fire department officials attending the ceremony urged the public to prepare for future disasters, and said people needed to be able to cope for being at least ‘two weeks on your own’.

Fire Battalion Chief Larry Collins added

The message for a lot of us needs to be, ‘Be ready for anything’.  The message used to be 72 hours, but we’ve seen in disasters like [Hurricane] Katrina, even [Hurricane] Sandy recently, that, really, if it’s wiped out your infrastructure, and your electricity grid and your communications, it will be very likely be more than three days before you start getting food, water and other supplies coming in from outside.

So there you have it, right from the horse’s mouth, as it were (here’s a link to the article).  Be ready for anything, and be able to cope for at least two weeks on your own (what we’d term a Level 1 situation).  That’s with no water, no sewage system, no external food supplies, and no electricity.

Update :  An interesting article came out in Seattle just five days later, with more detailed information on likely disaster response/recovery leadtimes in WA, OR and SFO, and quoting more officials rejecting three-day preparations as being adequate.  We discuss this in more detail here.

Mar 102013
 
This laser rangefinder can instantly display distances out to almost one mile, and also provides ballistic data for the long distance precision shooter.

This laser rangefinder can instantly display distances out to almost one mile, and also provides ballistic data for the long distance precision shooter.

We’ll be writing about the ‘old fashioned’ way of locating your secretly buried cache shortly, but wanted to also write, separately, about using high-tech tools when first establishing where a buried cache is, and then subsequently locating it again later.

There are three high-tech tools that some people might consider useful for locating their cache.  The first of these is a GPS unit, the second a laser range finder, and the third a metal detector.

All three devices have pluses and minuses, and in particular, we do not recommend GPS units.

The problem with such tools is simultaneously also their strength – they are high-tech gadgets.  They rely on batteries, and if they fail, you’ll almost certainly not be able to repair them.  If an EMP event occurs, they may be destroyed by the EMP effects.

We’re not saying you should totally ignore these three devices, and if they are in a suitable situation where they can work well, they’ll massively simplify your task.  But we are saying you should supplement them with lower tech calculations as well.

GPS Units

GPS units can be accurate, but usually not quite as accurate as you might think.  The accuracy which some GPS units show is not the complete calculation, it is the theoretical best case accuracy and fails to allow for some of the other fudge factors that affect GPS accuracy.  As a rule of thumb, double the imprecision it shows.

So if the device is telling you it is showing your location to within 12 feet, it is probably accurate to within 24 ft.

The most accurate units have a WAAS capability too – these are ground stations at fixed locations that provide additional reference location information in addition to the satellites in the sky above.  If your GPS is WAAS enabled, it will give very much more accurate information – sometimes locating you to within a yard or so of your actual location.

An earlier type of GPS improvement, known as DGPS, has largely been superseded by WAAS.

There is a further type of GPS improvement, probably used by your cell phone, which combines GPS information with location information from cell phone towers and possibly even known Wi-Fi locations too.  This information is primarily used to more quickly get a ‘first fix’ for where you are, but may also assist in improving accuracy too.  This is known as Assisted GPS, or A-GPS or aGPS.  Due to the reliance on many additional layers of data sources, and the expectation that you’ll be in a less dense area with fewer of these additional data sources, we expect that aGPS would be the first service to fail WTSHTF.

There are also special GPS receivers such as some surveyors use, which use additional signal processing techniques to create a more accurate position, potentially enhancing accuracy to as close as 3″ or so.  These are very expensive, of course.

The accuracy of a GPS is a ‘double whammy’ because presumably you are first making a note of your cache’s location by using the GPS receiver, and then subsequently looking for it with a GPS receiver, too.  So perhaps your initial location was 24 ft in error, with the real location being 24 ft north of you.  Then when you are attempting to return to the spot, the location error is now 24 feet in the opposite direction, so when you think you’re exactly at the location, you’re actually 48 ft away.  Even more misleading, the GPS might be showing a 12 ft accuracy in both cases, but you’ve ended up with the cache some 50 ft away.

Digging up a circle with a 50 ft radius involves 7850 sq ft of digging.  That’s a lot.

You can help improve the GPS’s accuracy by taking multiple readings, each reading an hour or two apart from the preceding one, over several days, and averaging the results.  This would give you readings from different alignments of different satellites, with different propagation delays, and would give you a more accurate average location.

This is helpful when recording the cache location in the first place, but you probably don’t have several days of spare time to leisurely plot an average position when the time comes to dig it up again.

There’s another reason to avoid relying on GPS units.  It is far from impossible that in a post-WTSHTF scenario, the constellation of GPS satellites may have been degraded or even completely destroyed.  In other words, GPS might no longer be available at all.

Even if sufficient of the GPS satellites and their signals remain, we’ll guess that the ground station corrections that are continually being fed into the satellites to update exactly their orbits and locations will cease, meaning that the accuracy of the GPS service will steadily degrade.  This degraded accuracy will not be apparent on your unit, but it will be happening; maybe only a few inches every day, but in a month, that could be another 10 ft of inaccuracy on top of all the other ever-present inaccuracies.  In three months, it might be 30 ft, and so you’re starting to reach the point where the GPS is becoming unhelpful rather than helpful.

GPS receivers also require a reasonably unobstructed view of as much of the sky as possible.  Dense foliage and tall trees will reduce their ability to accurately receive signals from as many satellites, which will degrade the accuracy of their position calculations.  A nearby hill would also block some of the satellites.

By all means take an averaged GPS fix as one of your multiple ways of recording your cache location, but consider it merely a tool to get close to where the cache is and then use other methods to exactly find it.

Laser Rangefinders

Laser rangefinders are one of three different types of range finders available – the other two being optical and ultra-sonic.  It is perhaps helpful to quickly consider these other two forms of range finder before concentrating on laser rangefinders.

Optical rangefinders can be useful, and are gloriously low-tech.  But to give any type of useful accuracy, they need their two viewing windows to be far apart, making them bulky, heavy and also very hard to find – they are not being made any more (as far as we are aware).

The way they work is such that the greater the distance they are measuring, the greater the error in their measurement.  The percentage error increases as distance increases, making the actual number of yards plus or minus become impractically large for the purposes of pinpointing a cache.  Furthermore, the units need to be regularly calibrated and all in all, a reasonable amount of skill is required to get best use from an optical rangefinder.

To given an actual example of optical rangefinder accuracy, here is the accuracy data that applies to a Wild TM-2 range-finder with a 31.5″ base (80 cm).  It’s best case accuracies are :

Accurate to within   0.05 m at 100 m (a wonderful accuracy indeed)
Accurate to within   0.5 m at 300 m (still workable)
Accurate to within   1.3 m at 500 m (starting to get a bit much)
Accurate to within   5.4m at 1000m (no longer very useful)
Accurate to within  21.5m at 2000m
Accurate to within  48.4m at 3000m
Accurate to within  86.0m at 4000m
Accurate to within 134.2m at 5000m
Accurate to within 193.6m at 6000m

This last figure has now become equivalent to a 3.2% error and of course useless for cache finding purposes.

Sometimes you might find an old ex-military range finder for sale; if you do and its price is low enough, it might be a fun thing to add to the pile of stuff you buy in the hope that one day it might come in useful for something, even if you’re not exactly sure what that use might end up as being!

Ultrasonic rangefinders are okay for indoor short distances, and typically max out at about 60 ft.  They are not so useful outdoors.

Laser rangefinders are the best solution for outdoors, and unlike optical rangefinders, their accuracy can/should stay the same, in terms of the plus or minus number of feet or yards, which means their percentage accuracy is actually improving, as the distance increases.

They are decidedly more accurate than any other type of rangefinder and also superior to most ‘normal’ GPS units, and unlike the GPS receivers, don’t rely on the reliable ongoing availability of a radio signal from somewhere/someone else.  They’ll calculate a distance, sometimes out as far as 1000 yds, between where you have the unit and a far away object that will reflect and return the laser signal from the unit.  The better the reflecting surface, the longer the range the unit is capable of, including sometimes greatly in excess of the unit’s maximum claimed range.

Military type units have even longer ranges, sometimes extending out beyond 10 miles (the distance to the horizon is only about 3 miles, so this is about as long a range as you’d ever be likely to need for most purposes not involving field artillery and other stand-off weapons delivery systems. Smile

Civilian units, usually sold for hunting or golf purposes, typically have an accuracy of within one yard; some of the new units are now getting reliably accurate to half a yard (18 “).  Sometimes the accuracy gets less exact as the range increases, although in theory that shouldn’t really be the case for most normal distances.

A laser rangefinder is certainly a very fast and easy way of taking multiple measurements for distances from objects, as long as the objects are suitably reflective.  If you’re in the middle of a field and can take measurements off fence posts on four sides, for example (perhaps with metal strips on them) you’ll quickly establish a very small zone beneath which your cache lies.

This obliquely indicates a requirement for a rangefinder to be useful.  There will need to be relevant landmark objects that you can measure distances to/from in several different directions, so as to establish the location of your cache.  If you are in an open field with nothing visible for a long way in any direction – or, for that matter, in a forest surrounded by identical trees – then any type of rangefinder would not be as useful.

On the other hand, do keep in mind that their accuracy is probably only within one yard, whereas measuring tapes, over reasonably short distances (ie one full tape length, perhaps 400 ft) are going to give you an accuracy of a few inches.  If you have some sort of probe (or metal detector – see immediately below) that you can use to quickly test if your cache is underneath you, then a yard or so is perfectly fine; but if the type of covering above your cache doesn’t allow for a thin metal probe, then you probably would appreciate greater accuracy from a tape.

The problem with laser rangefinders is they require batteries and are vulnerable to EMP effects.  They can also be weather dependent – if it is raining or foggy or snowing, their range will drop and maybe they’ll cease to function at all.

By all means, use one, but make sure you have backup tapes as well.  Expect to pay appreciably over $100 and up to $1000 for a very good ‘industrial’ grade laser range finder (with longer range, greater accuracy, more features, and stronger laser pulses that will bounce back off a wider range of objects).

Some laser rangefinders come with a sophisticated set of ballistics calculations to help you with long-range rifle shooting.  This can be invaluable if you anticipate the need for long distance precision shooting and have suitable rifles that give you that capability.

Needless to say, Amazon offer a good selection of laser rangefinders.

Metal Detectors

A metal detector can help you quickly locate your cache once you know its general location.  Depending on how much metal is buried and the type of soil it is in, a good metal detector will uncover objects as much as 15 ft – 20 ft beneath the surface.

This is both good news and bad news.  The good news is that it is tremendously helpful if you can use a metal detector to find your cache without having to dig up hundreds of square feet of ground.  The bad news is that your cache is vulnerable to discovery if other people decide to go looking for it with a metal detector too.

This page has an excellent explanation of metal detector capabilities.

If you were wishing to be really secure, and if you were anticipating organized searching for your cache, you’d probably deliberately place metal objects randomly all around likely areas that searchers might go looking for your cache, and you’d probably choose objects that looked ‘innocent’ like they could have been placed there by accident.  Of course, this would also destroy your ability to use a metal detector yourself to find your cache, so you’d have to decide which was the more important to you.

Although a good metal detector can cost over $500, it is probably a helpful tool to have – and, who knows, you might find yourself using it to, in turn, detect other people’s caches, too!

Summary

Although you shouldn’t rely on them as your only ways of locating your hidden buried cache, a laser rangefinder and a metal detector can make zeroing in on your cache a quick and easy process (assuming you have specific identifiable objects within half a mile or so on several directions that you can bounce laser beams off to triangulate your position).  Both items will cost some hundreds of dollars each, so they may not be the highest priority items on your wish list, and of course, until such time as you are about to start burying caches, you have no need for them (at least in this context).

A GPS can also help, but it is less reliable and probably less accurate than using a laser rangefinder.

Mar 092013
 
This shows how a side cutting can opener goes in through the side of the can/lid seam, and creates a replaceable top.

This shows how a side cutting can opener goes in through the side of the can/lid seam, and creates a replaceable top.

Here’s something you may not have thought about.  It is a small issue, but like so many other small issues, it is as easy (and sometimes easier) to ‘get it right’ and to do it in a fully optimized manner as it is to do it ‘wrong’.  So you probably should do it right.  And every small extra enhancement to your overall preparedness and ability to live better in a problem situation has to be a good thing, right.

With that as an opening, let’s now talk about can openers.  It might seem like a ridiculously trivial topic, but please do keep reading.

You of course know that can openers come in all shapes and sizes, of course.  There are the nasty primitive ones that leave a jagged edge around where they have ‘sawed’ open the can lid – these are the original types of can openers, and have only one benefit – no moving parts, and a lot of negative downsides (if you’ve used such openers and never cut yourself, you’re in a very lucky minority).

In the mid 1920s, a new design of can opener appeared, and it was further improved in the early 1930s, becoming the familiar two arm, hinged in the middle, opener with a cutting wheel (or maybe, more simply and not as satisfactorily, a stationary blade) on top and a matching pressing/turning wheel below.

We call these vertical cutters.  They cut down through the top of the lid.

More recently (we think about ten years ago) a new type of cutter started to appear.  This cuts horizontally rather than vertically, into the folded over seam between the lid and can body.  They were initially hard to find and very expensive, but over the last decade, have become more common, better made, and less expensive.

Although you doubtless have a drawer full of vertical can openers, most of which work reliably and well, we recommend you set them all aside and instead buy (and use) a horizontal type opener.  These are sometimes referred to as a ‘smooth edge’ type cutter.  They are only a little more expensive than a standard vertical opener, and they have two important advantages.

The first is indeed the smooth edge.  There’s less to cut yourself on, and while that might sound like a trivial thing, remember that any type of possible infection after TEOTWAWKI can be much more serious and even life threatening than is the case at present.  So the safer final result is a plus.

Talking about infection, some people also like the fact that the smooth-edge horizontal side cutter also doesn’t have its blade come in contact with the contents of the can.  This is a very small added benefit, but – hey – any benefit of any magnitude is better than a negative factor, isn’t it!

The second advantage is that the opened can becomes reusable.  You can press fit the lid back onto the can – this won’t give you a truly air-tight or water-tight seal – it is more ‘air resistant’ and ‘water-resistant’, perhaps.  However, it will definitely keep dirt, dust, and also insects, animals and hopefully rodents out of whatever you have stored in the can.

Most of our current storage concepts seem to involve plastic containers.  Sure, they can provide excellent barriers to oxygen and moisture, but they don’t provide any protection at all against rodents in particular, who will happily chew through plastic material without any hesitation.

So being able to put the side-opened metal lid back on the emptied can is a useful feature, although you then need some way to ensure the lid isn’t dislodged.  You could possibly solder it on in a couple of places, or in any of many other ways secure it in place.  The simplest method is just to put a rubber band around the tin and lid, or better to make it two at right angles to each other.

Sure, you can buy plastic snap on lids to put on traditional top opened cans too, but they are plastic and therefore vulnerable to rodents.

You may have heard the half-joke half-truth that long after man has vanished from the earth, there will still be cockroaches thriving everywhere.  The same is true of rodents.  We expect that with the changes that will occur in a Level 2 or 3 situation, rodents will necessarily become more aggressive at searching out food, just the same as people will, and anything/everything you do in terms of how you’ll store supplies needs to be done with an eye to keeping them as rodent proof as possible.

That’s not to say that rats can’t eat through metal cans, because they can and sometimes do.  But the can is at least a partial barrier and added layer of protection.  We would recommend packing foodstuffs in sealed barrier bags first, and then placing the bagged foods into washed and cleaned cans.  Keep the smell of food away from the packaging so as not to attract rodents.

This page on Amazon lists side-opening ‘smooth edge’ type can openers, but be careful.  There are a few traditional openers that have been miscategorized and appear in the results too, but if you read the descriptions carefully, and possibly look at the photos, you can see which is which, and even if you guess wrong, Amazon has a great return policy.

Some people have reported that they prefer units which don’t cover the top of the can – they find it easier to align the opener with the can if it is located to the side of the can rather than on the top.  Some people also feel that gears at 90° to each other are better than inline/parallel gearing.

The Amazon reviews will give you more insight into which units seem to prove the best in actual use.

You’d want to get at least two hand-operated openers, plus perhaps you might optimistically get an electric one too – both for use at present and for use in situations where the grid might remain up, or you have sufficient solar or other power to run appliances such as this (which happily use very little power).

We’ve been using side cutting openers for years ourselves, and while we sometimes find it a little harder to start the can opening, we love the results and would never go back to a standard can opener.  Try it, and you’ll probably love it too.

Mar 062013
 
Should you use a storage locker for your supplies?  If you do, we'd recommend parking your vehicle to obscure the view into your locker when visiting.

Should you use a storage locker for your supplies? If you do, we’d recommend parking your vehicle to obscure the view into your locker when visiting.

We’ve seen several writers recommend keeping some of your prepping supplies in a regular commercial self-storage rental-unit, instead of – or as well as – at your retreat.  They suggest you should choose a storage locker facility that allows you 24/7 access and which you can secure yourself and access externally.

People advocating this strategy say that using a commercial storage unit may be more secure than filling up your ‘cabin in the woods’ with everything you have accumulated, and they are half correct about this.

The part they are half correct about is that at present, with life as we know it continuing on in its normal fashion, your retreat is probably unlived in for much/most of the year, and therefore is vulnerable to attack.

It is close to impossible to make any type of structure totally burglar-proof.  Assuming your retreat is out of sight of the main road and neighbors, there’s nothing to stop burglars from using a crow-bar or chain-saw or in any other way, forcing their way into your retreat, at their leisure; and loading up anything and everything they want, completely undisturbed and unseen.

Your retreat is vulnerable not only to professional burglars but also to casual vandalism.  If people get the sense that there’s a little used mainly vacant house, they might decide to break in just for the sheer devilry of doing so.

On the other hand, commercial storage units are moderately secure and it is uncommon for individual units to be broken into.  The more secure storage units have individual alarms on each unit that will sound if the person renting the unit does not enter a personal access code prior to opening the door.

The least secure units have their doors secured by padlocks.  The reason this is insecure is that most padlocks can be defeated in only a few seconds by a pair of bolt-cutters; furthermore, after the thieves have cut off your padlock and entered your unit to take whatever they want, they can then re-secure your unit with a replacement padlock, leaving no obvious external sign of unauthorized entry.  Even worse, they could return the next day and simply open the padlock with their key, and for all anyone else would know, they were the rightful owner of the locker.  You’d not know anything about this until returning to the locker yourself to find an unfamiliar padlock on your door.

Issues and Risks of Storage Units

Some of the issues and risks to do with storing your supplies in a storage locker can be mitigated and reduced by prudent action on your part.

For example, if the storage facility you are considering does not have security that monitors and alarms any time a locker door is opened without an appropriate access code being entered, you could probably set up your own internal alarm at the storage unit so that when your unit’s door is opened, a disarm code needs to be quickly entered into an alarm unit, and if not done so, it will either sound a very loud alarm to alert the management and scare off the intruders, and/or dial a phone number to alert your or someone else about the unauthorized access (Use a Google phone number that will ring simultaneously to multiple numbers).  Clearly you want a storage unit with a power outlet, and an alarm with a battery backup.

There are two further vulnerabilities of a commercial storage unit.  Both are fairly small vulnerabilities, but one should not lose sight of them.

First, it is possible that the police or some other law enforcement body might get a search warrant to search an entire storage unit complex due to some part of it being suspected of being used to store something illegal (we are aware of this happening in a slightly different context with safe deposit box facilities).  If you had anything potentially embarrassing in your storage unit, it could be discovered in such a case, and while there would be a debate subsequently about if your items could be seized or not under the terms of the warrant the police were acting on, it would be at the very least an embarrassment and probably would require some time, trouble, and attorney fees for you to retrieve whatever it might be that the police seized.

Even if you had nothing embarrassing present, it is possible the police action could make everything unavailable for some time while they worked out what belonged to who and so on.

The other vulnerability could be the storage unit operator/owner breaking in to your unit – either illegally or legally.  Perhaps you set up some sort of regular auto-pay for the monthly rental, and maybe something changes to invalidate the payments, and maybe you don’t realize this, and the next thing you know, the owner/operator has broken in to your unit and is auctioning off its contents to recover lost rent, and has done something to everything else that you had stored there.

This happened to us.  We used a technique to obscure our actual identity when hiring the locker, but unfortunately, when the regular auto payments failed (unbeknownst to us), the facility manager couldn’t contact us, and we arrived one day to find our unit double locked by the manager, and about to be opened and the contents auctioned off.  Just as well we turned up when we did.

There’s another consideration to keep in mind as well.  It is a remote and unlikely risk, but it is also a risk that wiped out everything I had stored at a storage facility, some years ago.  This is the risk of fire (or any other sort of external ‘natural’ peril such as flood or who knows what).  You’ve probably seen pictures or video of floods, and I’ve definitely seen storage facilities suffering from flood waters the same as other businesses around them.  But in my case, the problem was fire.

A huge fire destroyed the large warehouse/storage facility, and its entire contents too.  There’s actually a weird ending to that story – I discovered that my regular homeowner’s insurance would cover me, and lodged a claim for what I’d lost.  The insurance company immediately paid out, but then almost as quickly, told me it would not renew my cover for the future, due to my having an ‘unexpected loss’.

Isn’t that what insurance is all about – protection against ‘unexpected losses’?  Apparently some insurance companies don’t realize or don’t accept they are in the business of covering for unexpected losses!  They are happy to accept your premiums, but don’t like to ever then pay out.

If you have your insurance cancelled/not renewed, you will find it very difficult to get alternate insurance at normal rates from anyone else, because all insurers tell each other when they blacklist a person.

So make sure you specify to your insurer that you are covering goods at both your primary residence and at a storage locker too; that way there will be less risk of your insurance company giving you a hard time if/when you make a claim.

Of course, there’s probably no way you’ll be able to effectively claim on insurance WTSHTF, but you could have a loss prior to then, and in such a case, you could indeed file a claim and get reimbursed.  And after life returns to normal after a major event, you may have some ability to get some sort of reimbursement from whatever remains of the insurance company – there’s a likelihood that whatever sort of government survives, will choose to help out in such cases.

The Moment at Which a Storage Locker Ceases to be a Good Strategy

So, while life continues normally, a storage locker is probably a good place to securely keep supplies.

But what about WTSHTF?  At that point, your retreat becomes comparatively more safe because you have people living there, and at the same time, your storage locker becomes massively less safe.

Our guess is that storage lockers will quickly become a high priority target for any roving hoards of looters.  If you’re not able to quickly – and safely – get to your storage locker and transport its contents to your retreat, then you run the risk of losing whatever you stored there.  Either the items will be stolen or it will become impossible/impractical/unsafe for you to journey to the storage locker and collect whatever you have stored.

This also indicates an important consideration when choosing a storage facility – its location.  You don’t want to use one in the center of a major population concentration.

You want to choose a storage facility on the outskirts of the population concentration, and on the same side of it as your retreat is, meaning that to travel between your storage facility and your retreat, you only need to go to the outskirts of the city, not into the center, and -worst of all – not through the city to a storage facility on the far side.

Op-Sec and Storage Lockers

If you are using a storage locker, you need to consider some simple ‘Op sec’ issues.

Assume that your every move is being watched whenever you are on the facility premises/grounds, and avoid doing anything unusual or ‘interesting’.  Move only nondescript things in and out of your unit.  Buy some packing boxes – plain brown cardboard boxes – and put whatever you are moving into these outer boxes.  That way, all any observer would see is you carrying generic cartons in and out of your unit.  That is much less tempting than seeing you carrying in boxes of food and ammo and whatever else.

Needless to say, if you are storing long guns – rifles and shotguns – either break them down so they too can fit in normal dimensioned cartons or choose cartons that have unnecessary extra width and/or depth to them so as to make it less obvious what is inside them.

We’d also suggest you don’t go to your storage unit too regularly, that you don’t load or unload too much stuff each time you do go, and that you generally go at semi-normal times of day or night, so as to seem totally ordinary and boring and not arouse any interest whatsoever.

But maybe do make a point of visiting once a quarter or so, and also make a show of taking things out of your locker as well as placing them in.  They can be empty boxes that you are moving, but just show some signs of using your locker for ‘ordinary’ purposes – ie as an overflow storage facility for a regular household where you sometimes put spare stuff into storage and sometimes take stuff out of storage to use.

If you had a taste for the theatrical, you could even do something like make a big show of carrying a box with part of an artificial Christmas tree sticking out of it in and out of your unit each Christmas season.

And, of course, try to minimize the potential for casual passers-by to see into your unit whenever you have its door open, and if there’s a possibility, try to keep stuff looking boring and ordinary inside your unit.

Summary

There is good sense in storing your supplies in more than one location.  If something might cause the supplies at one location to become unavailable to you, you still have your alternate location(s) too.

A storage locker can be a good place to keep supplies, but if you use one, you need to be careful at what you let people know and see about your stores, and will need to be able to quickly and safely clear out your supplies WTSHTF.