Primitive Archer
Main Discussion Area => Bows => Topic started by: chasonhayes on January 08, 2022, 03:55:27 pm
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I am making a hickory board bow. I found a board with very straight grain. I am following "A beginners guide to building a Hickory longbow" at 3Rivers sight. I am planning to back this with a reversed piece of 1/8" hickory.
1. Can I go ahead and glue the backing on before I start shaping while the the 2 pieces are essentially the same size rectangles? It doesn't make sense to me to shape the bow then separately shape the backing then glue it on.
2. If I put on an overlay for the tips should I put the overlay on top of the backing or should I stop the backing short of the overlay or does it matter?
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If you have straight grained hickory there is no need to back it at all.
1) I would glue the backing on while you have flat board shapes and then work it all to the final shape.
2) The overlay can go on top of the backing. Stopping the backing short is a recipe for the limb to break at that point.
Mark
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Thanks
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I agree with mmattockx... if you have straight grain no need to back. I would save that backing for another project.. gut
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I had already added the 1/8" backing by the time I read your reply. I have broken 5 bows so far and am getting a little gun shy.
I followed the instructions at 3Rivers exactly.
I am at the part where the directions instruct me to begin tillering and my bow is so stiff it won't bend at all. Here are the dimensions
The riser is 14" long with a 2 1/2" taper at each end (seems big but the instructions called for it)
Length 72"
Width 1 1/2" at the fades tapering to 1/2" at the tip
Thickness 1 1/8" at the fades tapering to 1/2" at the tip
The belly is rounded from 1/4" up from the back.
It seems thick but this is what the directions called for. Is there another thickness I should be aiming for before I can expect it to bend?
Please help
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Right...I've never seen the 3Rivers thing but....those are far from ideal dimensions for a hickory bow.
Assuming a 28" draw and upto 60#
Length 68"
Handle length - 4"
Fades - 2" each
Handle plus fades - 8"
Personally I'd have left the limbs wider like 1 3/4".
the limb taper would be a straight line from the widest point at the fades to the the tips at 1/2" This is called a pyramid bow and the limbs would bend in close to an arc of a circle - this makes tillering much easier. By the sounds of it the 3Rivers dimensions are more like an elb style. These sort of bows need to be tillered elliptically (for optimal strain and position of limb weight).
Flat belly with hickory. A rounded back would be a better idea.
The reason board bows are backed is if the grain isn't straight enough. Truely straight grained hickory is a backing! Your other bows could have broke for many reasons but most likely is using a board that didn't have straight enough grain.
please post pictures of where you are at.
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riser is way too long.. bownarra has some great dimensions there.. gut
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Here are the pics
I can shorten the riser to the recommended dimensions if you think this is wise
Also what thickness is good to begin with for a pyramid bow design?
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Here are the pics
I can shorten the riser to the recommended dimensions if you think this is wise
Also what thickness is good to begin with for a pyramid bow design?
A shorter riser gives more working limb, which is always a good idea on a wood bow.
If you go with a straight pyramid width taper then the limb wants to be nearly constant thickness from fade to tip. For true circular tiller you need to taper the thickness of the outer 1/3 of the limb or so, but starting with constant thickness and working into the thickness taper works fine. I would say reduce the thickness to 5/8" out of the fades and keep that thickness to the tip as a starting point.
As bownarra says, keep the belly flat and I would recommend also keeping the back near flat as well. A slight crown will be OK with hickory. You are limited to the weight you are going to get with the 1 1/2" width but that should still get close to 40lb@28".
Mark
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Thanks. For the future should I start with a 72"x1 3/4"x5/8" piece?
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Thanks. For the future should I start with a 72"x1 3/4"x5/8" piece?
Yes, or even 2" wide. There is no penalty for starting too wide and then narrowing it as you tiller if you need to. Especially with the pyramid back profile, ending up with a bit of extra width at the fades is no problem and costs virtually nothing in performance because the tips narrow down and don't carry extra weight that hurts performance. If you are having trouble with breaking bows as you learn I would suggest that keeping extra width is a great way to increase your chances of success.
If you are buying boards that really means starting with a nominal 1x3 size that actually measures to 3/4"x2.5" and then cutting it to the width you want and working from there.
Mark
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I have a plank and I size my piece from it so I can make it any size I want.
2" wide got it
How thick should I make it to start? 3/4" or 5/8"?
Also should I offset the handle? I see some instructions say to make the top of the handle 1 1/4" up from center to 2 3/4" down as opposed to 2" up and 2" down
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1" above center line is top of handle 1 1/4 would be arrow rest or shelf if added and start of top fade 3 inch below center bottom of handle start of fade. Fades can be 1 1/2 to 2"..make sure your glue on handle is above start of fade where working limb starts.. this will prevent handle from popping off at full draw.. I agree with 2" wide limbs for starts. can always thin down if need be.. handle area should not be any longer than 8 ".. 14 was way too big.. the more working limb is better.. I draw 26.5 and rarely make a bow over 62"..most are 60".. I add when laying out this way you will end up with a longer upper limb .. about 1 1/4.. its a matter of preference .. I like the way the bow balances in hand laid out this way.. just as easy to till too.. gut
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here are the adjustments based on the comments
The first shows the step cutt method to remove waste
The second shows the end result after smoothing
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I have a plank and I size my piece from it so I can make it any size I want.
2" wide got it
How thick should I make it to start? 3/4" or 5/8"?
Also should I offset the handle? I see some instructions say to make the top of the handle 1 1/4" up from center to 2 3/4" down as opposed to 2" up and 2" down
The 3/4" dimension is just what the lumber comes at. 5/8" is lots and you will almost certainly end up under 1/2" thickness with hickory for a ~40lb draw weight.
The handle details are somewhat personal preference. My risers are usually ~10" long, the pivot point is on the center of the bow and the arrow rest is 1.25" up from center. You do need to offset the handle the way you describe it, you want the center of the bow about where the web between your thumb and forefinger will rest. Here is a pic of my last bow. The pivot point is the deepest cut-in portion of the grip and is on the center of the bow, so my handle is offset downward.
(https://i.imgur.com/sOhXV1F.jpg)
Mark
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here are the adjustments based on the comments
The first shows the step cutt method to remove waste
The second shows the end result after smoothing
You posted while I was doing the same. That looks pretty decent as a starting point. Are the limbs starting to bend yet at that thickness? The limbs of a 40lb bow are surprisingly flexible if you do a floor tiller test bend. If you need a lot of force to move them then they are still too thick.
Mark
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Thanks. What dimensions should I use to achieve a 50lb draw weight with hickory pyramid design?
What draw length should I use?
My wingspan is 71" tip to tip
From the thumb webspace to midline is 30"
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here is the first tiller. It looks like I have some string follow. suggestions please?
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Thanks. What dimensions should I use to achieve a 50lb draw weight with hickory pyramid design?
What draw length should I use?
My wingspan is 71" tip to tip
From the thumb webspace to midline is 30"
You should get 50lb out of the 2" width, but probably with some set involved. I would suggest a length of 66"-68" nock to nock for a 28" draw. Longer is more forgiving to make and shoot.
Have you ever shot a traditional bow before? If not, 50lb is way too heavy for a beginner. There are online draw length calculators but they are only approximate. The only way to know for sure is to draw a bow (preferably light weight so you aren't fighting it) and measure. If your draw is over 28" I would suggest adding a couple inches to the bow length to be on the safe side.
here is the first tiller. It looks like I have some string follow. suggestions please?
If you are taking set then you have already pulled it too far at that thickness and draw weight. I see you have a bow scale. You want to use it while tillering and never draw the bow past your target weight while tillering it out. Only pull to your target weight, then remove material to get it to pull farther before you hit your target weight again. Rinse and repeat until you get to your target draw length and weight. If the bow is taking set and you haven't hit your target weight then it is never going to get there and you need to adjust your target weight down some and start working towards that.
The pictures have some distortion in them, but it looks not bad in the first pic. Maybe a bit stiff out of the fades and on the outer 1/3 of the limb, but not terrible. The right limb looks to be bending more mid-limb than the left.
Mark
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It’s hard to tell how the tiller is with those photos. As was said above the distortion makes it hard to judge. The right outer limb seems stiff though but can be certain.
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Here is a better shot of the tiller.
My next question is how do I match arrows to it for backyard target shooting?
What if i were to put recurve tips on it? Would that make it better?
This bow is a learning experience for me and not going to last very long for sure but i want to get the most out of it as I can.
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That looks to be doing all of its bending right out of the fades. I would take wood off both limbs from maybe 5-6" out of the fades to the tips. The left limb especially is looking stiff from mid to tip. Don't touch anything near the fades until the rest of the limbs are bending more or you will have a hinge going there. Recurving the tips adds more stress and is harder to tiller, I wouldn't recommend it until you have successfully made a few bows and have a better feel for tillering.
Mark
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yeah i agree with MMattockx, dont touch the fades again until the rest of the bow is bending with it.
i would wait on recurves, i just made one and it was fun, but it wasn't as great (or as easy) as I made it out to be in my head. :)
Excited to see your progress!!! ;D