Primitive Archer
Main Discussion Area => Bows => Topic started by: Puckaway on September 05, 2014, 12:20:19 pm
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This is my knotty hickory build I've been working on. Its a real challenge working these limbs. Any advice is welcome. So far I've only pulled it to about 45#@ 20"
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Hard to say for sure, but Id say your fades are working too hard and your mid limbs are flat.
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Hard to say for sure, but Id say your fades are working too hard and your mid limbs are flat.
Me too
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Hard to say for sure, but Id say your fades are working too hard and your mid limbs are flat.
Me too
+3
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Noted. I'll get the mid limbs bending more.
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Use a straight edge and trust it.
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I started off using a gizmo, but someone told me it would be useless on this bow on account of the knots.
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I have no use for a gizmo myself. I suppose I could be accused of not knowing how to use it properly.
A straight edge allows you to view a span of say 6-8" (depending on how long it is) as a cumulative area rather than putting pencil marks on all of it.
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On a bow like that I'll use a credit card or drivers license whichever I grab from my wallet first. If I can't pay someone to tiller it I'll drive to somebody that can :o
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That's reassuring Jon.........:)
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Seriously though I like a small straight edge when dealing with a lot of character in a bow. Don't worry Chris I usually only end up with one maybe two hinges per limb ;)
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You'd be a fool not to take that advice Jon. A mostly blind man can clearly see you know how to make wood bend precisely.
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So.. Should I use like a 6" piece of wood to check for gaps and flat spots and focus on the flat spots until they match the gaps?
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One thing I do is take a pic and use a CD or something similar. Hold it up to the pic of the bow to see the bend. Works like a charm. The other method is good too I'm just not as familiar.
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You might want to put up a pic of the unbraced profile so that everyone knows what your starting with. Without the unbraced photo, most assume you started with straight even limbs and give advice based on that assumption. Unless you straightened all the character out of this stave, the straight edge/gap/gizmo techniques are pretty much useless with one exception. That exception is to take a long straight edge and draw a line down the side of the limb and use the line as a reference to where its bending and where its not. Josh
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I guess I've just gotten lucky with my short straight edge. Never new it was useless. Maybe that's why it works for me ;)
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By your work Jon, it's obvious that you can make it work. But on a rollercoaster like this I don't see how. It's nothing but deflex kinks with longer reflex bends in between. I just can't see how a straight edge is gonna help get all the different angles sharing the workload equally. In my admittedly limited understanding of this stuff, getting a even "looking" bend on a decicedly uneven starting profile is gonna end up with the deflex kinks doing nothing while the reflex portions in between carry all the load. What am I missing? Josh
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Josh it's easy to over think things. Where I think it helps(for me anyway) is to use the straight edge on either side of an area like you are showing. Obviously you can't make a straight line through an area that has severe roller coaster you just get it working even on either side and know that you need to focus on the problem area. Does that make sense? When I say I use a straight edge I mean like four inches max and usually three inches. Josh I also tiller with a belt sander which everyone knows can't be done either. I am serious when I say that sometimes things work when you don't know they "can't".
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I'm looking at the picture that Gun Doc just posted. That thick area right between his thumb and forefinger. Should that be thinned out to follow the back more or would that weaken that spot too much?
Don
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if the bow has a deflex spot,, that part will looks like it is working ,,,even if it is thicker ,, it is not,, basically the taper has to be even,, so you have to go by the thickness of the wood, as well as the way you think it looks bending,, a good example is ,, if the bow has a bend that is reflexed,, it is easy to make that part of the bow too thin,, to make it "look right".. then you get a hinge and say what happened, ,it was bending even,, but you forgot to keep the taper even as well(the wood was not working even the reflex was working way more to make the bend even to your eye),,,it just takes more experience to tiller the odd one,, because sometimes you are going on feel and how the wood is tapering,, not how it looks bending,, at full draw they usually look better when the wood has been tapered well,,, :)
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I will take more pictures in the AM. Stay tuned.
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DC's got it right. The belly should follow the back with a slight taper to the tips. The areas around the knots will and should be a little stiffer than the surrounding wood but you can remove more wood around those knots without weakening that area.
I find with these irregular bows if you squint your eyes while viewing the bend helps. It eliminates the details so you can see the overall bend better.
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Do these help?
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And a couple more.
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U should have an even thickness in all the humps and stuff. From the pics they look a lot thicker.
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Hi....try this ;)
if you can get it on a pulley system, you can just watch it bending. check that each area is flexing, regardless of reflex or deflex. Try to watch each 5 inch section in isolation, whilst keeping an over all picture. look through almost closed eyes....sometimes this helps, it takes out all of the surrounding 'interference'
Just keep drawing it on the pulley, looking at it, going away, and coming back and doing it again. you will soon get the eye for where it is bending and where it isn't.
.......it helps me ;)
Matt