Primitive Archer

Main Discussion Area => Bows => Flight Bows => Topic started by: DC on August 22, 2020, 03:54:55 pm

Title: Bow riser question
Post by: DC on August 22, 2020, 03:54:55 pm
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?
Title: Re: Bow riser question
Post by: Badger on August 24, 2020, 09:13:47 pm
 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.
Title: Re: Bow riser question
Post by: DC on August 25, 2020, 09:41:15 am
I made the 50#(hopefully)12", maybe 11".
Title: Re: Bow riser question
Post by: avcase on August 26, 2020, 02:38:14 pm
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
Title: Re: Bow riser question
Post by: DC on August 27, 2020, 09:21:39 am
Thanks for the responses guys, at least I know that nobody knows ;) ;)
Title: Re: Bow riser question
Post by: Selfbowman on August 28, 2020, 08:00:43 am
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. 😁😁😂
Title: Re: Bow riser question
Post by: DC on August 28, 2020, 09:07:56 am
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?
Title: Re: Bow riser question
Post by: loefflerchuck on August 28, 2020, 09:15:43 am
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.
Title: Re: Bow riser question
Post by: DC on August 28, 2020, 09:37:50 am
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.
Title: Re: Bow riser question
Post by: Selfbowman on August 28, 2020, 03:51:29 pm
DC what I meant was simple composite to complex composite. A fade is a fade is it not??? Just asking? Arvin
Title: Re: Bow riser question
Post by: DC on August 28, 2020, 06:01:40 pm
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?
Title: Re: Bow riser question
Post by: Selfbowman on August 28, 2020, 07:55:49 pm
DC I guess I’m confused too never mind. Arvin
Title: Re: Bow riser question
Post by: avcase on September 17, 2020, 02:53:03 pm
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
Title: Re: Bow riser question
Post by: DC on September 17, 2020, 04:27:40 pm
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"
Title: Re: Bow riser question
Post by: avcase on September 17, 2020, 05:44:37 pm
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
Title: Re: Bow riser question
Post by: willie on September 17, 2020, 05:48:03 pm
...providing the built up portion of the handle does not bend...
this statement is not only ambigous, it is technically false.

providing the built up portion.... does not...... act as an additional laminate in the working/bending areas of the bow limbs.

any length specified will be changing the intent if it can bend

if the rule gets put on the table for amending, should the intent be clarified first?
Title: Re: Bow riser question
Post by: DC on September 17, 2020, 06:53:22 pm

any length specified will be changing the intent if it can bend


And everything bends :D
Title: Re: Bow riser question
Post by: PatM on September 18, 2020, 05:44:49 am
It does seem like people could be reasonable about judging whether the added on bits are purely to build the thickness back up versus trying to cheat a lam into the harder working portions of the limb.
Title: Re: Bow riser question
Post by: DC on September 18, 2020, 11:08:21 am
It does seem like people could be reasonable about judging whether the added on bits are purely to build the thickness back up versus trying to cheat a lam into the harder working portions of the limb.

The problem with that is that people aren't reasonable :D especially if you put them in a position of authority ::). If you leave it up to judging you will have different rulings fron one meet to the next.
Title: Re: Bow riser question
Post by: willie on September 18, 2020, 11:53:34 am
and if the bow in question were a bendy handle design, would it be a working trilam?
Title: Re: Bow riser question
Post by: DC on September 18, 2020, 12:08:55 pm
That crossed my mind too.
Title: Re: Bow riser question
Post by: avcase on September 18, 2020, 04:38:54 pm
The problem with that is that people aren't reasonable :D especially if you put them in a position of authority ::). If you leave it up to judging you will have different rulings fron one meet to the next.

Don,
This is very true!  This is why I like to make it as clear as possible in the rules.  I find it important to avoid very open ended statements.  The event officials who will be checking your equipment may also be a competitor. Clarity helps eliminate real or perceived bias when that official needs to make a judgement.

I know that added pieces bonded to the handle area for the self bow and simple composite has been allowed since the beginning.  I think in every case, the added on material fades into the main limb, and this does technically make the bow into a limited multi-laminate. Specifying a maximum length for this does provide a clear limit. So I feel this could be a good approach. Is 12” too much?

An alternate solution is to disallow added in pieces at the handle for all future self bows and simple composites.  Would this be better?  It may mean bows used in prior years can no longer be shot in the same category in the future.

Overall, I feel our primitive rules are pretty good. The rules managed to avoid the pitfalls of trying to conform to a traditional standard. Instead, the rules attempt to focus on the materials and how they are used, and leave it up to the archer to figure out how to come up with the most effective design to get the job done.

Alan
Title: Re: Bow riser question
Post by: DC on September 18, 2020, 05:21:20 pm
I remember when I was racing RC sailboats. If you wanted the boats to be simple the rules got complex. If you wanted the rules to be simple the boats got complex. 12 " sounds great to me. Maybe write it in like " a third lam is permissible in the center 12" " to cover Willie's bendy.
Title: Re: Bow riser question
Post by: mmattockx on September 18, 2020, 11:28:32 pm
Specifying a maximum length for this does provide a clear limit. So I feel this could be a good approach. Is 12” too much?

Too much for what? If it is a hard number it doesn't really matter much what the number is. You have an objective standard that is not subject to (much) opinion/bias and it is consistently the same for everyone, which is about all you can hope for when setting out rules for a competition like this. Specifying how many decimals the measurement will be made to and what the allowable measurement error is would help to further define the allowable limits.


Mark
Title: Re: Bow riser question
Post by: PatM on September 19, 2020, 07:02:42 am
Adding wood to a riser is generally just done  to re-gain thickness or overlap a splice.    It could maybe be shortened a bit from 12 inches to eliminate the extra belly lam grey area.

  Sounds like the rules guys at an event need to be  non-competitors.   With no friends competing either. lol
Title: Re: Bow riser question
Post by: willie on September 19, 2020, 10:56:17 am
specifying any length would be an addition or change to the rule.
 
If any measurement is to be incorporated into the rule, it should be to clarify what was originally intended. Define and measure the bend.
Title: Re: Bow riser question
Post by: Selfbowman on December 31, 2020, 07:38:26 pm
My handles are 9-10”fade to fade. For a fifty pound bow . I have built 100# bows with 10” handles. Just make the add on’s  add after 1 “thickness in the riser or handle. Sorry DC  you might need more yew. Not trying to be smart or hard ass. Most all selfbow rules state one continuous piece of wood or two billets joined in handle. They make no mention of any other laminates at all. But I’m ok with what ever is decided. At that point Its just the rule. Arvin