Saturday, May 12, 2012

How to Build a Primitive Bow Saw in the Wilderness


I'll be the first to admit that a good, sharp axe is my favorite bush tool. It can do almost anything you need, whether it be chopping down a dead tree for firewood, bucking and splitting logs, or even creating feather sticks. The problem is, an axe is just plain heavy.

I pack an axe whenever possible, but reality can be a cruel mistress when hiking through the wilderness. That extra 3 pounds of forged carbon steel and hickory can feel like 50 pounds when added to a backpack already loaded to capacity with food, water and other multi-day backpacking essentials.

So what do you do if you're into using serious wood processing yet can't bear the weight of an axe? -- Improvise! By packing just a 2 ounce bow saw blade and a 3.5 ounce Mora fixed blade knife, you can literally saw 10-12 inch thick trees in half which then can be used for firemaking, shelter construction, etc. Yes, it sounds hard to believe, but I'll show you how to do it and it's actually quite simple.

A dead Aspen tree sawed cleanly in half with a primitive bow saw made from a Spruce branch:

Before going any further, I would like to thank Ben's Backwoods for sponsoring this article, as they were gracious enough to send us a pair of Swedish Bahco bow saw blades to use. I have been buying axes and Mora knives from Ben's for years, and the service has always been excellent. Ben is a well respected member of the bushcraft community, and is also an expert on axes, saws and knives, so he's a great person to deal with if you have questions about the product you're buying. Please check out his internet store. He has a lot of cool stuff!

THE TOOLS YOU WILL NEED

  1. 24" Bow saw blade (please see my "Raker-Tooth vs Peg-Tooth blade" write-up below to decide which one you need)
  2. Some type of self-made sheath to safely hold the bow saw blade (can be made of cardboard and Duck Tape as shown in the article below).
  3. Two 1" diameter metal key rings (available at local hardware stores)
  4. Swedish Mora Fixed Blade Knife (almost any model will work)
  5. Multi-tool with a wood saw blade-- any multi-tool with a wood saw blade will work, but if you're counting ounces, I'd recommend something like a 2.6 ounce Victorinox Camper Swiss Army Knife or a Coghlan's Pocket Sierra Saw. (NOTE: In a survival situation, you can use just your knife to baton through a branch to make the bow saw)

Shown in the photo- Bahco Peg Tooth 24" Bow Saw blade, Mora FireKnife by Light My Fire and a Victorinox Camper Swiss Army Knife.
                                                                                        (click to enlarge)

DISCLAIMER! Do not try this technique without heavy leather work gloves and safety glasses. The teeth on a fresh bow saw blade are razor sharp and can cause serious injuries. ALWAYS carry a wilderness first aid kit. If you try this technique, try it at your own risk. Rocky Mountain Bushcraft is not liable for any injuries sustained. There is inherent risk in all wilderness survival techniques, so be extremely careful at all times!

Finding and selecting a bow stave to make the saw

Almost any green softwood branch can be used to make a bow saw, but softwood isn't very durable and might not hold enough tension on the saw blade for optimal use. When possible, always seek out the strongest and most flexible wood available. Here in the Central Rockies, we are rather hardwood-challenged so-to-speak, since most of the forests are covered with softwoods like Pine, Spruce, Fir and Aspen (Aspen is technically a Poplar which is considered a hardwood, but it is actually softer than many evergreens). 

As mentioned, these softer woods can certainly be used in a pinch, but if you can find hardwood like Rocky Mountain Maple, Serviceberry, Gambel Oak, Box Elder, Wild Locust, Mountain Mahogany, Water Birch, Choke Cherry, or Juniper (a softwood, but good for bows) your bow saw will last longer and be more effective at keeping tension on the blade. Willow is also a good option if you can find it.

For those of you outside of the Rockies, there are usually more options. Yew or Vine Maple works great if you're in the Northwest. Osage Orange found in the Mid-West is one of the best bow-woods in the world. Hickory, Ash, Oak, Elm and Maple are classic choices for those in the Northern Mid-West and Eastern parts of the country. Birch and Willow are also common in these areas and would work in a pinch.

If you're in California, no need for a bow saw as it never rains or gets cold there! Just kidding. The Oak and Juniper that's found in the mountains of California would make great bow-wood. Scrub Oak and Mesquite down in Texas and Arizona might also be useful for this technique. If you know of other good bow-woods please leave a comment below.

PHOTO: Dave standing in front of a large, scraggly Rocky Mountain Maple tree at about 9,000 ft elevation. Rocky Mountain Maple trees are technically considered shrubs, but their wood is actually a variety of Hard Rock Maple, so it's very strong and flexible. The leaves and seeds look almost identical to other Maple trees providing an easy way to identify them (if it's winter, look on the ground for dead leaves and seeds for positive identification).

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How to construct a primitive bow saw

If possible, try and find the best bow woods in your area to procure a proper stave to make your bow saw. In the photo above, this tree was not a suitable prospect because all the branches were extremely crooked.

However when we went around to the other side of this rock formation we found another Mountain Maple that had straighter branches that we could use to make our bow saw (see photos below). If all you can find is softwood, it will still work but it won't be as durable. (see the demonstration further down in the article where I cut an Aspen tree in half with a spruce bow saw).

IN THE PHOTO BELOW:  I sent Dave to do the dirty work of finding and sawing off the stave while I got to lounge around and take photos! Note the Mountain Maple growing around a mature Aspen tree:

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IN THE PHOTO BELOW: Dave is breaking out a Coghlan's Pocket Sierra Saw while inspecting the tree for a good stave to cut. For the purposes of demonstrating a potentially life-saving wilderness survival technique, we cleanly pruned one branch off of this Mountain Maple to make our bow saw. Please be a good steward to the land and only cut what you need. Always minimize the footprint you leave in the backcountry!

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Sawing off the stave (yes, that's a Bear Grylls Ultimate Fine Edge Survival Knife that we're testing for Gerber hanging on Dave's belt).

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Success!


Preparing the stave

In the photo below is the Mountain Maple branch we cut, along with the bow saw blade, and a crude cardboard and Duck tape sheath I made to safely hold everything while in my pack. 

Note the key rings linked together on one end of the bow saw blade. This makes it easier to safely grab the blade when pulling it in and out of the sheath, plus it keeps both rings attached securely. As you'll see, these key rings make constructing the bow saw faster and easier than using wooden pegs or a section of a branch to hold the bow together. Thanks to Ben Piersma of Ben's Backwoods for sharing the key ring tip with me!

(click to enlarge)

Since I mentioned making a crude cardboard sheath to hold the bow saw blade, I also wanted to mention a more expensive, but incredibly cool alternative for carrying your bow saw blade into the backcountry-- Bushcraft Northwest's Leather Survival Belt with a bow saw blade inside.


Bushcrafting legend Mors Kochanski is known to have made a custom leather belt to carry a bow saw blade with him, so Bushcraft Northwest owner Mike Lummio took Kochanski's idea and ran with it, creating a leather survival belt which holds a Bahco 24" Peg-Tooth bow saw blade inside. The screws on the belt are removable and are made to secure the ends of the blade into a primitive bow saw. If James Bond were a bushcrafter, he'd certainly be wearing one of these!


Now let's get back to building a primitive bow saw!

The next step is to delimb the branch. This is easily done with a Mora and Swiss Army saw as shown. Once the branch is delimbed, measure the length to be cut by placing the Mora alongside the bow saw blade and stave as shown below. Pretty much any standard Mora will work. I placed the Mora's handle to match with the second hole in the bow saw blade. If you don't have a Mora, you can always do it the old fashioned way by bending the stave to the desired curvature and marking it for the cut. If you do have a Mora, this just makes the procedure easier and faster.

(click to enlarge)

Now that stave is cut, find the natural bend in the wood. You will use this natural bend when "stringing" the bow saw, just like with a regular bow that shoots arrows. Once you find the natural bend, mark the ends of the stave to align with each other. These will be slots that the bow saw blade fits into. 

In these photos, I am not wearing gloves for demonstration purposes ONLY. Unless you are in a true survival situation, always wear leather work gloves and safety glasses when practicing this technique!

(click to enlarge)

Now that the stave is marked and ready, it's time to create the slots that will hold the bow saw blade by batoning your Mora knife into each end as shown. In an emergency, this can also be done with almost any pocket knife, locking or non-locking. The baton shown on the left is a dead Aspen branch sawed with the Swiss Army knife.

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Now that the stave is ready, attach the key rings at both ends of the saw blade as shown.

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Place the end of the saw blade into one of the slots. It's also a good idea to carve a shallow notch into each end of the stave to help anchor the key rings in place. It should look similar to this:


"Stringing" the Bow Saw 

Place the stave against your leg as shown in the photos below and gently bend it while also pulling on the key ring to set the blade in place. Once again, I'm using bare hands for demonstration purposes only-- always wear gloves and safety glasses when trying this technique! And in case you missed it earlier, use ONLY green wood to make bow saws. Otherwise, you might end up having a bow saw snap in half and a razor sharp bow saw blade flying towards you - not good! 

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Before I go into the field test to show you how well this saw can perform, a discussion about the two common bow saw blade styles is in order.

Raker Tooth blade vs Peg Tooth blade- which one to choose?

For this particular test, I used a 24" Bahco "Peg Tooth" bow saw blade. In the world of bow saw blades, there are two main blade designs-- the "Raker Tooth" and the "Peg Tooth." In the comparison shot below, the Peg Tooth is the blade with the smaller teeth shown above, and the Raker Tooth is shown below:

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The difference between the two is simple. The Raker Tooth is designed for cutting green wood, which is soft and moisture-laden and which quickly loads up the saw channel with debris. This can rapidly deteriorate the saw's effectiveness. The Raker Tooth is designed to "rake out" the excess debris, which maintains the efficiency of the saw, hence the name. I've also found Raker Tooth blades to be a better choice for sawing through highly resinous fatwood/pitchwood.

Peg Tooth blades, on the other hand, are designed for cutting dry wood. The performance advantage of Peg Tooth over Raker Tooth blades in dry wood is dramatic. In my independent tests, a Peg Tooth blade out-saws a Raker Tooth blade by roughly 50%. The downside is that Peg Tooth blades tend to gum up faster when cutting green wood.

Still, for a survival saw blade, I'd rather carry a Peg Tooth if I could only choose one, since cutting firewood to stay warm would be a top priority. The nice thing is that these blades only weigh 2 ounces a piece, so you can easily carry both styles to handle any wood cutting job that arises.

Field Test/Demonstration

To demonstrate the effectiveness of our primitive bow saw, we performed three tasks-- 1) sawed a dead branch off of a downed tree 2) sawed a dead Ponderosa Pine tree in half, and 3) sawed a dead Lodgepole Pine tree in half.
 
Test #1- I was able to saw this branch off 3-4 times faster than I could with my Bahco Laplander 7" folding saw:

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Dave sawing a dead Ponderosa Pine in half:

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Dave sawing a dead Lodgepole Pine tree in half (I had to fight with him to get the saw back because he was having way too much fun with it!)

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Primitive Bow Saw from a green Spruce branch

As mentioned earlier, you can use almost any green branch if necessary. To demonstrate this, I went on a separate mountain trip with my stepson and made a primitive bow saw with a green spruce branch. 

With this spruce branch version, I was able to saw a dead Aspen tree clean in half with it. This bow saw didn't last very long, but I could have sawed enough firewood to last for several hours before it broke. 

I also sawed off a dead Aspen branch to make a baton as well as a smaller log to make kindling as shown below.

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The baton would be used with the Mora to split the smaller log into kindling-size pieces in order to get a fire going. Once a smaller fire was going, the larger logs could be added to build an all night fire to stay warm.

(click to enlarge)
 
Conclusion

To make a long story (and article) short, if you want to bring lightweight yet heavy horsepower for wood processing/survival, just carry a two ounce bow saw blade along with a Mora knife. There is no other combination that can beat the amazing performance-to-weight-ratio that this highly capable pair offers.


About the author
Jason Schwartz is the founder and senior editor of Rocky Mountain Bushcraft. He is a former Red Cross certified Wilderness & Remote First Aid Instructor, and has taught bushcraft and wilderness survival techniques to the Boy Scouts of America, interned with the US Forest Service, and studied wilderness survival, forestry and wildland firefighting at Colorado Mountain College in Leadville, Colorado. Jason has also written for magazines such as The New Pioneer and Backpacker, including writing the "Tinder Finder" portion of Backpacker's "Complete Guide to Fire," which won a 2015 National Magazine Award (NMA). Email him at rockymountainbushcraft @ hotmail.com (without spaces)

4 comments:

  1. Very good info guys (and gal), that belt looks pretty nifty for carrying the saw blade too. I've always wanted to give one of these a try and I think it might go on the to-do list for my next outing.

    -OutdoorEnvy

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    Replies
    1. Thanks Outdoor, really appreciate that. Yes, we have one in our hands right now and it appears to be a functional design. Should have a full review up soon!

      Cheers, Jason

      Delete
  2. The key rings make it easy to do this! Ingenious Idea!

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  3. Thanks. I wish I could say I invented the idea but I got it from my friend Ben Piersma at Ben's Bens Backwoods :)

    ReplyDelete