Primitive Archer

Main Discussion Area => Bows => Topic started by: Bowyer Wannabe on August 02, 2018, 05:23:56 pm

Title: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Bowyer Wannabe on August 02, 2018, 05:23:56 pm
I was watching reviews of Mead Longbows on YouTube and I noticed that the maker builds the siyahs on those bows to be super thin - the siyahs on all Mead Longbows are no more than 1/4 of an inch thick, if not thinner.
So I was wondering: what kind of wood is best for making such thin siyahs? It must be a wood that is strong enough to withstand a shot without shattering, it must be sturdy enough not to bend sideways when the bow is strung, and at the same time it must be very lightweight.

What is your experience with syiah woods? Which wood would allow me to make razor thin siyahs?
Thanks!
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: sleek on August 02, 2018, 06:16:01 pm
When i make them i laminate bamboo on either side of an osage core. The shorter they are the less the will twist on you. 1/4 thick sounds like a nightmare. I made them thin once and the alignment had to be perfect. Its at bracw and full draw when they really wanna twist on you. Id really not recommend them, and especially that small, and very especially if you never made any before.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: PatM on August 02, 2018, 07:50:17 pm
Any reasonably dense hardwood with the grain flipped vertically will work fine.   Ash and Maple are both good and I think that's what Dave uses.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Mesophilic on August 03, 2018, 12:34:18 am
I bought two of Dave Meade's kits a while back and both sets were maple.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Bowyer Wannabe on August 03, 2018, 07:37:38 am
Thanks, guys. I have access to ash, so I guess I will go with it.
Ash is a bit heavy, but the thinness of the design should compensate for this.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Del the cat on August 04, 2018, 01:07:36 am
You can help the stiffness and reduce weight by staying a tad wide but making them slightly "T"  "Y" or "V" cross section.
Del
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: High-Desert on August 04, 2018, 09:35:12 am
This is purely speculation, but would strong per weight woods work best, allowing you to stay a bit wider, yet still be light? Like spruce? I've always kind of wondered, anyone know?
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Tom Dulaney on August 04, 2018, 12:01:17 pm
I'm in the process of building a Xiongnu-type composite bow (wood and sinew, no horn) and I'm using Chinese privet for the siyahs. They are approximately the dimensions you describe, with a tapering cross section as Del the Cat described.

Privet grows everywhere in the midwest and eastern USA, can often be found growing bent as branches of appropriate diameter for making siyahs with good grain. It dries quickly but you have to cut the siyahs to your dimensions quickly and seal the ends or the pieces will crack.

The wood is very tough for its weight and I think my siyahs will work well for my bow, even though there are a couple of pin knots and a weird grain irregularity.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Halfbow on August 13, 2018, 08:33:03 pm
I actually was wondering this myself a few months ago, and I made a table of wood strength to weight ratio, just pulling numbers from www.wood-database.com (http://www.wood-database.com). I got these numbers simply by dividing the modulus of rupture by the average dried weight. My thinking was, this would tell me the woods that could be the lightest without breaking.  I can't vouch for this list as being a good indication of siyah woods, as I imagine there are many more factors to consider, but it seems like a good place to start.


Higher numbers are better:

Bamboo
356-461

Black Locust
404

Jatoba (Brazilian Cherry)
395

Katalox
389

Pignut Hickory
387

Black Walnut
384

Bloodwood
383

Ipe
372

Olive
363

Hard Maple
359

Ash
357

Poplar
348

Osage Orange
345

African Mahogany
330

Red Oak
327

White Oak
316

Inspired by this list, I made some jatoba siyahs that worked out great. They are quite extreme, are about 1/4 inch thick, and have no stability issues.

(https://i.imgur.com/jTMnwkl.jpg)

(https://i.imgur.com/30GlKyF.jpg)
There's a super thin layer of osage on each side of the tips, with the grain at a 90 degree angle to the jatoba.

(https://i.imgur.com/byuWLzl.jpg)

(https://i.imgur.com/GE8YfrY.jpg)
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: lebhuntfish on August 15, 2018, 04:53:41 pm
Take this with a grain of salt,  but Sweet Gum is probably the hardest and lightest wood I have ever worked with.  I have some cut up in my yard right now as well as needing to cut the rest of the tree.  Let me know if you would be interested, maybe we could trade if you like. 

Patrick
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: lebhuntfish on August 15, 2018, 04:57:18 pm
Any reasonably dense hardwood with the grain flipped vertically will work fine.   Ash and Maple are both good and I think that's what Dave uses.

Dave usually uses hard maple.  But if I remember right him and I had a long discussion about Sweet Gum wood as a siah. 

Patrick
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: simk on August 16, 2018, 04:52:02 am
@ Halfbow: Your bow seems very very interesting to me. Is there a presentation with more of these beautiful details?
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: Halfbow on October 15, 2018, 12:46:20 am
Thanks simk. Not currently, I need to have a proper photo shoot with it. I will get around to it one of these days and make a thread for it.
Title: Re: Best wood for siyahs on a horse bow? Aiming for a razor thin design
Post by: simk on October 15, 2018, 04:30:34 am
Thanks Halfbow - appreciate that and looking forward! Cheers