Bow riser question

[DC]

I'm going to try and build a 50# bow for next year but have a question I would like to clear up. Is this kind of riser going to be considered a third lam/power lam if it's too long. How long is too long?

[Badger]

 You are pretty close on that one but I think ok, I will try and look it up tonight but I believe 14" is the limit to remain in the simple comp class. As soon as I can find it I will check back in.

[DC]

I made the 50#(hopefully)12", maybe 11".

[avcase]

This is an excellent question. This points out a weakness in the rules that needs some clarification. Otherwise, we will risk inconsistent judgements by officials or we will see it become something that is intentionally exploited by devious guys like me!  Haha!

I think it makes sense to specify a maximum length, and that this will apply to both inserts at the handle as well as glued on blocks that are used to build up the depth of the handle. The addition of an illustration would go a long way toward making it clear for competitors and officials. I think this will be a good topic for discussion at Bonneville.

This would apply to the Simple Composite, and self bow. The self bow doesn’t have an insert, but it does allow addition of added pieces to be glued to the handle in order to build up depth.

Alan

[DC]

Thanks for the responses guys, at least I know that nobody knows

[Selfbowman]

DC that’s some beautiful work on that handle layup. I don’t think that’s a selfbow but I also don’t think it will give anyone an advantage. But I’m not a engineer. Just make your fades thicker. I don’t care as long as your arrow does not go as far as mine. 😁😁😂

[DC]

Thanks Arvin. That handle started because I was running out of Yew and came up with that design in order to use thinner cut "boards" for the limbs. That meant running the riser out into the limb for thickness. I've now decided that 7/16" thick is enough to keep the riser length down to 12" or less for a 40# bow. If I'm feeling really cheap I can cut a 13/16" board kind of on the diagonal and get two limbs out of it. When I get more Yew I won't have to concern myself with it so much.
 It has a Boo backing so it's not a selfbow anyway, is it?

[loefflerchuck]

Seems like a fair rule would be- if it extends to the bending section it is a layer. If it's stiff it's just a handle lam.

[DC]

That would be the intent of the rule but how do you test something like that? The bend just slowly diminishes as you move toward the handle.

[Selfbowman]

DC what I meant was simple composite to complex composite. A fade is a fade is it not??? Just asking? Arvin

[DC]

DC what I meant was simple composite to complex composite. A fade is a fade is it not??? Just asking? Arvin

I'm confused, what are we talking about?

[Selfbowman]

DC I guess I’m confused too never mind. Arvin

[avcase]

I would like to dig into this issue some more. As of now, there isn’t any maximum length specified for additional pieces that can be used to build up the handle in a self bow or simple composite bow.

The rules only says the following:

“Wooden handle built up blocks may be added, providing the built up portion of the handle does not bend or additional blocks act as an additional laminate in the working/bending areas of the bow limbs.”

This leaves it up to an official to make the decision on the spot, and this risks inconsistent enforcement.  Any added block of material or insert in the handle does affect how the bow bends to some degree. So I feel that this statement in the rules is ambiguous and needs revision. I think specifying a maximum length with an illustration is the best way to fix this.

I wouldn’t want to specify a maximum length that is any more than it needs to be. 12” seems plenty long for building up the handle area. I figured 10” could even work.  I know I would take maximum advantage of this feature if I were building this kind of bow.  What do the rest of you think?

Alan

[DC]

The only reason I made this style of handle was to maximise the use of the yew I had left. If my belly lams were 1/2 or 9/16" thick instead of the 3/8" shown in the picture. The feathering out part could have been easily pushed toward the middle by up to 2 1/2" on each side. That would make it 7-8" rather than the 12" shown. The thing is, I don't think it would affect the performance at all. It's a nice way to make a bow as it uses up small pieces. I would prefer the 12". It looks nice and the thinner lams are easier to steam bend.
What other reasons would someone have to push this rule?
All that said I'm sure their are other designs that might take advantage of a new rule and that may change the whole face of the class.
Is there another way of defining the working/bending area of the limb? If not then I think you just have to pick an arbitrary length. Somewhere between 8 and 10"

[avcase]

I know I would take advantage of this for the same basic reasons. It allows use of thinner wood, and it works better with my process for building a bow. In fact, I had a hickory and ipe set of lams several years ago that my daughter were going to use for a simple composite flight bow, but a mistake left the ipe board a bit too thin. A 12” double wedge in the handle would have made it viable again. We didn’t do it at the time because I feared the ambiguous wording in the rules could have been interpreted in a way to disqualify the bow.  It seemed like my daughter and I were always in trouble for one thing or another.  I took took the rules literally, so I would often have some feature on our equipment that wouldn’t always match the what those officiating expecting. It was never due to an effort to cheat, it was just a matter of coming from different backgrounds. This is why I feel it is important to take on these questions, and take the time to add clarity to the rules.

I think 12” is pretty reasonable proposal. It is easy to check, and solves a number of potential problems. 

Alan