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self bow?

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13K views 29 replies 11 participants last post by  Silent Bear  
#1 ·
I am thinking of making another self bow.I have made two so far and they did ok but after awhile both end up cracking.I have never made one with a backing yet.will the backing keep the bow from cracking?If so what combanation should i use for it?I want to be able to get the belly and backing at lowes or somewhere like that if possible.i have seen lots of diff combos,maple and hickory,walnut hickory and so on.what do yall think is best?
 
#2 ·
Concrete. That should stop your bow from cracking and it'll let you go up to 200# draw weight. :teeth:

I'm making my first selfbow, too, and it was recommended to use cloth, silk or sheet rock tape (ugly!) for backing, attached with wood glue. Yes, backing will help stop the bow from cracking because it holds in any splintering pieces instead of letting them spread.

I'm interested in hearing what other people say about different woods for backings though.
 
#3 ·
As far as wood backings, bamboo is excellent but my favorite is hickory. Another I've used in the past with good results is elm. Elm has a nice tight, interlocking grain pattern that holds together really well. I liked using it on less dense woods like maple. If you want to go the nonwood route, rawhide is very hard to beat and has been time proven to be an excellent backing material. If you don't mind a little more work and mess, sinew is an awesome backing material to work with, particularly when working with shorter length limb bow designs. Not only will it hold down splinters and keep the bow together, but it generally will induce a little reflex into the bow while it's drying Linen and heavy cotton cloth have been used as well, though I have no personal experience with them. I have used silk in the past. It seemed to do well. To apply many of the above mentioned materials, I've used the titebond series of glues with good results. I've also use Urac 185 to laminate the wood backings. With the sinew, hide glue is the way to go.
 
#4 ·
I'd venture to say that if you left the inner limbs a little wider, that alone should prevent eventual cracking (so long as yuo got them bending enough to be useful).

For normal use, I prefer cotton cloth. Prevetns fracture and it's easy to apply/decorate.

For wood, bamboo works- but should be much more narrow than the limb on woods like walnut, oak, maple, etc. Hickory backings should be slightly round on the finished bow for the same reason.

With sinew, well- I love sinew:). It seems to work best on bows 66" or shorter, with 66" also having the best compromise for speed and stability on average anyway. I use Knox gellatin (yeah, the stuff from the grocery store) and then coat it in a thin smear of Titebond III. Takes longer, and requires more materials etc., but it helps hold bows in a little bit of reflex and allows you to push design limits (or cover up design mistakes:D).
 
#7 ·
i like maple for backing on medium density woods, but any flaws (like figuring) can explode after a few hundred shots. i cut my teeth on hickory boards. i'd buy an 8/4 flat sawn hickory board for $30, then rip backing strips off of the edges & make a couple selfbows from the center. you end up with a couple opportunities to chase a ring on a board. it makes for good practice, and soon you'll be hacking down chokecherry staves & splitting your own elm (have fun with THAT!).....
 
#8 ·
what i have so far is a 1/2" red oak backed with 1/4 in maple.Its all glued up and dry now.when i flex it a little it feels to be a little stiff still.I am looking for around a 45# at 28".it is 72" long but am planning to cut to 68 amo.I have found two diff plans online.one is with belly tapered form riser to tips and one where limbs stay same all the way.will it work not tapering them?it doesnt seem like it to me.what do you think I should now?and can i still back the maple backing with silk?or should i?
 
#11 ·
what i have so far is a 1/2" red oak backed with 1/4 in maple.Its all glued up and dry now.when i flex it a little it feels to be a little stiff still.I am looking for around a 45# at 28".it is 72" long but am planning to cut to 68 amo.I have found two diff plans online.one is with belly tapered form riser to tips and one where limbs stay same all the way.will it work not tapering them?it doesnt seem like it to me.what do you think I should now?and can i still back the maple backing with silk?or should i?
I'm assuming the one where the limb isn't thickness tapered is a pyramid design and yes it works well. The tiller is more influenced by the limb width taper than the thickness taper in that design. I've made several pyramid design bows and find that I still have to tiller the belly a little bit. The limb thickness does come out fairly uniform in the end though. It's come to be one of my favorite designs in an all wood bow.

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#9 ·
If you're going to use oak boards, the key element is to get one with perfect, perfect, perfect grain orientation. If there's any runout, grain swirl, or other flaws, you'll be playing with a hand grenade if you try to turn it into a bow. If the store you're in doesn't have such a perfect board in their racks, walk away.

In lieu of boards, my suggestion to beginners is to find a straight, clean osage or hickory stave and make a bow from that. They're more work, more expensive, and not as easily available as running to Lowe's, but those woods can tolerate more tillering and "process" errors than red oak lumber and you're far more likely to turn out a solid hitter on your first attempt.

I know it runs against popular opinion, but I feel board bows, despite there being less work, are better left to more advanced bowmakers. Backing with a 1/8" strip of hickory or rawhide is great insurance for boards, too.
 
#10 ·
This is a short tutorial from Tim Baker. He has made literally hundreds of bows. He even made the main bow used in the Scorpion King movie.

YOUR FIRST WOODEN BOW

Following is a 40-50lb design that is easy and quick to tiller, is durable, accurate and fast, and costs about six dollars to make.
This bow is the length of your finger-tip to finger-tip wingspan. Its side-view shape is that of an English-tillered longbow. This design’s grip is part of the working limb itself, making the bow easy to layout and easy to make. It stores more energy than shorter bows, draws with little stack, and is more stable and accurate than most. It may have a larger number of good features than any other design. These instructions call for a lumberyard hardwood stave. With such a stave it’s possible to read this in the morning and be shooting your bow the same afternoon. Not likely, but possible.
If you don’t have access to such lumber do this: Cut a straight hardwood tree, split it down to four-inch wide wedges, take the bark off without damaging the wood surface. With saw or hatchet reduce the stave to your wingspan plus a few inches. Reduce it to two-inches wide from end to end, 1” thick at the grip, ¾” at midlimb, and 5/8” at the nocks. Set it horizontally in the warmest, driest part of your house and wait a month. Allow air to move freely over all its surfaces.
Selecting a lumber stave: Use any of the medium-weight or heavier hardwoods. White ash, rock maple, hickory, pecan, mulberry, red or white oak, yellow or white birch, black walnut, etc. Seleect a board whose face displays almost perfectly straight ring lines, with no meanders, islands or kinks. Pay no attention to ring lines on the side of the board; they can be misleading; they don’t need to run straight. Although on the rare perfect board ring lines will run straight on both sides and back. Viewed from its butt end, the board’s rings can be flat or angle through the board. Beginners should avoid boards having vertical ring lines. You will likely have to look through 50 or more boards to find a sufficiently straight-ringed stave.
Tools: A hatchet and a rasp are all that’s absolutely needed. But a spokeshave and coarse and medium rasps make the work faster and easier. A block plane is helpful if used carefully. A bandsaw saves about two hours of roughing out.
Front-view layout: With a sharp pencil and a straightedge draw the bow 1 3/8” wide from midlimb to midlimb. From there draw a straight taper to ½” nocks. Reduce the stave to these dimensions. Don’t stray past the line. Create smooth, square sides. Smooth out the slight angle created where the midlimb begins its taper toward the tips.
Side-view layout Draw these lines on both sides of the stave: Let the center six-inches be 3/4” thick. Moving toward the nocks, let the next two inches taper to 5/8 then to 9/16” at midlimb, then to ½” at the nocks.
Reduce the stave to those dimensions. Don’t stray past the lines. Let thickness changes be smooth and gradual. Remove the wood from one side of the belly at a time, with the tool at a slight angle, such that when both sides are done a slight crown will have been created along the center of the belly. Then remove the crown. It’s important to reduce belly thickness this way. Otherwise at some point you’ll dip below the line on the opposite side and ruin the bow. This method also averages out any errors of reduction. It’s also easier than trying to remove full-width wood.
As you remove wood down to the pencil lines frequently sight along the length of the limb from a very low angle and make sure your work is smooth and uniform, with no dips or waves or dings. THIS IS ONE OF THE MOST IMPORTANT PARTS OF BOWMAKING--if thickness taper is smooth and gradual it’s difficult to break a bow.
Narrow the belly side of the grip just enough to cause a nocked arrow to rest square against it. Do this on both sides of the grip. Round all corners of the grip.
Tillering Cut string nocks with a rattail file or similar, then string the bow with a slightly slack string. Set the center of the grip on one end of a tillering stick--a 30” one-by-three board or similar--and place the string in a notch cut into that board, causing the bow to bend about five inches. Lean this rig against a wall then back up and inspect the curve of your new bow.
The shape you are seeking should not be part of a circle, but more the shape of a satellite dish antenna—an only slightly bending grip, with each portion bending slightly more than the last as you move from grip to mid outer limb. Elliptical tiller. The last ten inches or so bend should be a bit stiff, with less bend than midlimb.
It would be good to draw this shape on paper and have it ready to refer to while tillering..
If your bow does not take this shape, or if the limbs are not curving equally, make pencil marks on the belly where the limbs are too stiff. Remove wood from these stiff areas, first on one side of the belly, then the other, then remove the slight crown created. Do this with long sweeping strokes, creating no dips, waver or dings, frequently sighting along your work, as above. THIS IS ONE OF THE MOST IMPORTANT PARTS OF BOWMAKING.
When the curve finally suits you brace the bow about five-inches high with a proper-length string and inspect it again. Mark any stiff portions and reduce them as above. When content with the curve draw the bow to half its intended draw weight, measured by your best guess or a scale. Set the bow on the tillering stick at this length of draw and mark any stiff areas and remove as above. Re-check the tiller, re-mark, remove wood, etc. until perfect curvature is reached.
Now draw the bow to full draw weight. If full weight is reached at, say, twelve-inches of draw you need to remove medium amounts of wood all along the bow’s length. Do so by above methods, check for proper curve on you tillering stick. Correct where needed.
Again draw to full weight, now at possibly fifteen-inches of draw. From this point on remove only paper thin amounts of wood at a time. Pull to full draw weight after each curve check, setting the string into ever farther notches on the tillering stick as draw length increases. But only for a few seconds at a time. Once within five inches or so of full draw inspection time should drop to just a second or two.
This process of drawing to full weight after each tiller check--Jim-Hamm tillering--insures that you never come in under intened draw weight, the most common failing of new bowmakers.
Continue this process until about one inch short of intended draw length. Smooth all surfaces to your taste, slightly round the corners, and you’re done. The bow will settle right into its intended weight.
If using hickory, pecan or rock maple 50lbs is a safe weight. Redoak or ash or elm will be safe at 45lb. If birch or black cherry stay at 40lb. As your tillering skill improves these weight can rise several pounds.
When tillering is near complete, and if the tips are straight—causing the braced string to sit centered over the grip--narrow the last ten-inches of outer limb down to 3/8”. This softens any hand shock and increases cast. If the string is slightly off center narrow the tips only on the offending side. This will bring to string back toward center.
Nock the arrow just above the center of the grip. The arrow will fly more accurately with one limb or the other as the top limb, but this may change over the life of the bow.

Tim
 
#13 ·
Another from Tim.
The following 50lb bow is almost identical, but has a narrower, more comfortable grip. This bow is half-way between 'first bow 'and "Your Third Wooden Bow," which will be a shorter, wider-limbed, narrow grip, Comstock design. Some prefer a shorter bow for hunting. "Your Fourth Wood Bow" will require a split stave, and will cover tillering difficulties encountered when leaving the placid waters of board staves.

As with 'first bow,' the following instructions assume a straight-ringed board stave. If you don't have access to such then use a tree-split stave prepared as described in 'first bow.' To make this bow you will need to print the opening instruction from that thread.

Choose a board on whose face ring lines can be seen runing from one end to the other in almost perfectly straight lines, with no kinks or waves, and fairly parallel with the face of the board. The fibers that make up such a board will then parallel the board surface/bow back, and the original surface of the tree. Pay no attention to how ring lines may appear on the side of the board. Trust for the moment that this makes no difference. Use any of the heavier common hardwoods.

Lay out this bow exactly as 'first bow' except

-- Let the 1 3/8" limb read 1 5/8".

-- Narrow the center 5 " of the bow to 1 1/4 ", widening gently to 1 5/8 ". This 1 1/4 " grip will be narrowed further if the strength and thickness of your board will permit.

Reduce and tiller as for 'first bow' except that the center 10" or so will be stiff to the eye.

When approaching final tiller, if the stiffness of the wood will "ow, narrow the 5" grip by very small amounts on each side until you can FEEL [not necessarily see] the grip barely bending in your hand. It's very important that this narrower wood not bend anywhere near as much as near-grip limb wood. Thicker wood will not bend as far before breaking.

This 'second bow' is a little more trouble to lay out than 'first bow' but is more comfortable to shoot. It's a good transition bow to have under your tillering belt before making the more difficult wider , shorter, 'third bow.'

And another.










STAVE SELECTION: Same as in 'First Bow,' except that the board must be two inches wide, but can be about 66" long. The same tools will also be used.

FRONT-VIEW LAYOUT: If you draw 28" this bow will be 66" long. Add or subrtact two inches for ever inch you draw long or short of 28". Mark the stave at the center of its length. Draw the handle one-inch wide and five-inches long. During the next two inches let the grip widen to the stave's full width of two-inches. Taper to 1 3/4" at midlimb. From midlimb draw straight-line width taper to 3/8" nocks. Reduce the stave to these dimensions. Be careful not to tray past the lines. Create smooth square sides. Smooth out the angle where the midlimb begins it's taper. If using a common 13/16" board or similar glue on a 12" long board of the same or equally stiff wood to thicken the handle. Lightly scrape both surfaces before gluing--to remove air-born oil. Be careful not to create a crown on either.

SIDE-VIEW LAYOUT: You will be drawing thickness taper lines on both sides of both limbs. Make target thickness marks on both sides of both tips, 3/8" from the back. At 5" from the tips make 1/2" marks, And at midlimb, again, 1/2" from the back and on both sides of both limbs. Six-inches from where the limb begins to narrow at the grip make 5/8" marks. Mark where the grip first begins to widen. Mark the grip 1 1/8" thick. On both sides of both limbs connect these marks with a sharp pencil line, careful to make any thickness changes smooth and gradual. At the near-grip 5/8" marks let the rise to the grip begin very gradually then become progressively steeper.

Reduce the stave to these dimensions, narrow the grip belly, cut nocks, and tiller the bow, all as per directions in 'First Bow,' with these exceptions: Since the outer limb is a pyramid design this portion will stay almost the same thickness along it's length. Remove enough belly wood here for the limb to bend, but no more than at midlimb. When finished tillering round the corners somewhat, especially the back corners. This is a durable, efficient design which should cast a 500-grain arrow about 160fps. Please ask for details or clarification if needed.


Maybe this will help someone.
 
#16 ·
On that bow pictured, the limbs started 2" wide near the handle and straight tapered to 3/8" at the nocks. Length, NTN, is 67". The limbs are right at 1/2" thick. It pulls 47#@28". It's made of hickory. I've heard of folks going wider with shorter designed pyramids..
 
#17 ·
To prevent the bow from cracking you need some kind of strong material that will prevent the wood fibers from coming up when in full draw, I would recommend that you use animal sinew to hold these wood fibers down and this will also increase the poundage of your bow, if sinew is not availible to you then I would try and buy a string of some kind like hemp to hold these fibers down, if you would like more help feel free to message me
 
#22 ·
I myself have never tried that but I imagine its worth a shot anything will work as long as it holds the fibers down on the bow while adding little weight
 
#26 ·
for me it's pretty simple: if a selfbow creaks, i glue linen on the back. i've had a few that looked perfect suddenly decide to blow up (if you ain't breaking any, you ain't learning!!)

wow- silent bear, you're getting 26" from a 34" bow??? i really want to see a build along. i have a pretty good ape index, so i'm working a 62" juniper stave for sinew backing first.
actually, i have 5 juniper bows started right now (and a pile of sinew ready to be pounded & combed), so how about a build along anyways?

every stave is perfect!- it's our interpretations that fail
 
#27 ·
every stave is perfect!- it's our interpretations that fail
I really like that:D.

I've used some pretty knot-riddled, twisted, crooked, messed up sections of wood- and wound up getting full draw, heavy weight longbows without a backing (numerous times). Truth be told, I think I've only ever been able to work maybe two or three pieces of actually CLEAN wood. But considering I'm not a short bow fan, and the low tensile strength of juniper you use, backings aren't an issue for me like they are for you. I use hickory and white oak for the most part- woods very high in tension strength.