Primitive Archer
Main Discussion Area => Bows => Topic started by: Wooden Spring on February 14, 2014, 03:24:03 pm
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OK, so I'm FINALLY going to be starting a Mollegabet this weekend... I've got a board glued up that's a hickory backing (1/8") an ipe core (1/8") and a jatoba belly. It's got 1 1/2" of reflex glued into it.
The drawing below is a culmination of a lot of research that I've done on the thing, does it throw up any red flags, or should I be good to go with this??? I've built a lot of Pyramid bows, but this is my first Mollegabet...
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I'd happily use these specs as a starting point, ...though I might go a bit longer for the overall dimensions.
OneBow
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So, where should I be for overall length? I have a 28" draw...
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1 3/4" is to wide for ipe even in this design i'd start maybe 1 3/8", takes very little ipe to hit 60#, I cant read all the numbers so I cant see the length but 64"ntn would be safe
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1 3/4" is to wide for ipe even in this design i'd start maybe 1 3/8", takes very little ipe to hit 60#, I cant read all the numbers so I cant see the length but 64"ntn would be safe
It's just 1/8" strip of ipe in the bow, the belly is jatoba. Jatoba has about the same specific gravity of ipe, so it performs about the same, I've just got the ipe in there for color. I like the jatoba because it performs like ipe, but without the skull splitting headaches that I get when breathing ipe dust... That stuff is evil!
The bow is 68" long. I thought it might be a bit heavy, but I can always take wood off the sides if it feels like it's going to be too much.
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With a backing of 1/8" and a core of 1/8" you'll end up with hardly any jatoba belly in the extremities of the working limbs. A core is really not needed for this design, and might even be detrimental. Either make this core thinner (about 1/16") or just use no core entirely. With a wood as stiff as jatoba and ipé, you'll end up with really thin limbs. And 1 3/4" is indeed too wide as well.
By the way, what draw weight are you looking for?
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I would have left the jatoba out.
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I would have left the jatoba out.
...and made the ipé thicker or use several lams of 1/8" ipé.
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1 3/4" is to wide for ipe even in this design i'd start maybe 1 3/8", takes very little ipe to hit 60#, I cant read all the numbers so I cant see the length but 64"ntn would be safe
It's just 1/8" strip of ipe in the bow, the belly is jatoba. Jatoba has about the same specific gravity of ipe, so it performs about the same, I've just got the ipe in there for color. I like the jatoba because it performs like ipe, but without the skull splitting headaches that I get when breathing ipe dust... That stuff is evil!
The bow is 68" long. I thought it might be a bit heavy, but I can always take wood off the sides if it feels like it's going to be too much.
Jatoba has no where near the compression strength of ipe. It might have similar density, but that's not the only factor to consider in belly wood.