My 2015 bow

[Badger]

  Mark, I would really like to see you try a couple of the componets in one of your bows some time. I feel like I took your design to a large extent and added a couple of tecnique componets. I have a feeling it would come out much better if you did it.

  Just for the heck of it I am going to list some of the problems I have had with highly reflexed bows and how I dealt with it here and with what results. The funny part is it all seemed to go back to one issue that solved a lot of problems.

1. Problem with tips too far behind the back,  instability, limbs would tend to rock back and forth at brace. Shorter bending area solved that problem. Solid as a rock.

2. Problem, instability, limbs twisting especially at brace with too much limb contact. Again short working area solved that problem. Seems very solid at brace with only very slight tendency to want to twist.

3 Problem, loss of efficiency due to heavy tips and vibration and distorsion throughout the limb. The heavier tips were needed for stability to keep the string from comming off. Again the shorter working limb proved less sensitive to outer limb mass simply because it has no room to vibrate or distort improving efficiency.

4. Problem, takes set increasing histerias. Here I was lucky to get a low crowned osage stave which allowed me to go very flat and wide. Not always possible. God blesss osage. I think the design is really made to order for glass bows or at the very least backed laminated bows where you can keep them flat and wide.

5. force draw curve. Not sure if the curve I used is close to optimum or not, long sweeping 12" radius designed for a lot of string contact at brace. The results seemd good but others may very well be better.

6. Heat treating, Makes a lot of things formerly not possible possible.

I don't think this would be practical for most white woods as they would need to be about 3" wide I imagine. Might be real well suited to ipe with a hickory back. Anyway thanks for all the kind words but in all honesty I cannot claim I hit the 200 mark with a bad chrono. I wouldn't accept less than a verified test to claim that and wouldn't expect you to either.
 

[Marc St Louis]

I can see how this bow gave you fits Steve.  It's a bit like this bow that I made years ago, only yours is a bit more extreme.



That bow gave me fits as well and it didn't take long before the HHB belly started to develop chrysals.  I just don't know if I want to tackle another and if I was I would most certainly use a more elastic wood even than HHB.  Yew would be great with this design

[Del the cat]

....  Yew would be great with this design

Del's ears prick up and he scampers off to check his Yew stash

[Aaron H]

I wish I had a yew stash.   

[DC]

I've got a couple of deflexed yew staves that want to look like that Don't think if I'm up to it though Steve, have you tried Ocean Spray for that design?

[Badger]

DC, ocean spray would do great in that design. The only problem would be that you will have a hard timew finding one with no crown that yu can keep wide. If you go a bit less reflex maybe 3" max and allow a bit more working limb it should make a killer bow. More like Marks bow above.
I wouldn't even attempt that style if I couldn't have a flat bending portion in the limb.

[sleek]

Elm could do it crowned,  but I havent been able to get it to bend that well for reflex.

[Badger]

   You think so Sleek? I haven't run into a wood yet That I feel could do it crowned. Elm is a good candidate for large diameter trees which have very low crowns but I think it would need to be 3" wide minimum. Several factors at work you may not fully understand.

[sleek]

Hehe, "I reserve the right to be wrong " should be my tag line. But yes, in all respect to you Badger, I think it can. I have done some retarded stuff with elm that held when it shouldnt have. Though you are probably right about forces I dont fully understand.  For fun of it, im going elm hunting this weekend to golive it a try. Elm holds an advantage with interlocking grain.

[Badger]

  If holding together is your goal you should do it easily with elm.

[Badger]

  Sleek, I think it is about priorities. When you get a super pice of wood with a low crown and good species, clean etc it opens up a lot of design options you won't have with a lesser stave. My first priority when making a bows is not overstraing the wood, working within its elastic limits. If that means I build a straight bow then thats what I do. If it means more working limb then thats what I do. It is always my first priority. As far as I am concerned a bow can be ruined long before it breaks.

[Marc St Louis]

Why would you want a low crown?  Personally I would think that a higher crown would be the way to go, not too high mind you.  I've always found that a higher crown tales stress off the belly

What was wrong with your chrono Steve?

[blackhawk]

@marc... Because with such short working limbs you need wide limbs,and if the crown is too high you cant get the width you need.

Call me crazy but I think a piece of good clean black locust would do well for what your wanting as well. Its about as stiff and bend resistant as osage, but its lower density leading to light outer stiff levers. It doesnt take much locust to make your levers stiff(just as small as osage actually). Plus its a very snappy fast returning wood. IMO those combinations make for a fast dry fire speed. And a good piece is def strong enough in compression and elasticity to maintain healthy wood. But that's just my experiences with it.

The only other wood I'd try besides osage,yew,or locust is hickory. I hate to say it,but a good DRY piece of hickory can deliver the goods in this design as well. Just keep it no higher than 6%mc before and after its made,and design and tiller it right. Plus if your taking it to the salt flats it would really do well there as ya already know.

I'd put elm and hophornbeam at a distant 4th. They just vary to much from piece to piece in properties to gamble on. Although I have had one elm and one hhb make it and throw an arrow pretty dang far.

But I understand why one wood only want to use osage or yew in these designs as in my experiences have shown them to be more proven,and a higher consistency of success of making a bow. I've tried designs similar to this in a LOT of different woods. Other woods "can" work,and when they do they turn out awesome, but theyre just not as consistently durable to such stresses.

[Badger]

    Mark, one thing I have never really got into or fully understould is the trapping effect, which is similar to have some crown. Intuitively I feel more confident with as flat as I can get a back. Some exceptions to this are when making long bows with long bending limbs. I have no idea why it just seems to work. The bow in question here does have a slight crown it measures .300 at the crown in thickness and about .260 at the edges. I consider this pretty flat for a 2" wide bow. Easy to find in hickory and elm but no so much in a lot of other species.

    As for the chrono, the process I use involves me first shooting a glass bow that I know the speed of when shot from a machine. I use this to calibrate myself and my shooting tecnique and release. I don't have my shooting machine set up at present. Not real scientific but close enough for my purposes. My brand new chrono I put an arrow through testing out that 100# short osage bow so I dug through the box trying to get one of my old ones working. After about 8 or 10 shots without first checking myself I got two readings. I can't say if they are accurate or not with any kind of certainty or reliability. I can easily push a shot beyond its actual speed. So for that reason I am not making any claims on hitting a milestone.

      What I will claim on this design which is a large part based on Mark St Louis designs and can be replicated is that putting together a series of little tecniques we have come to understand over the years will allow for a minimum of tradeoffs and compromises that all of us have come to understand so well.  My workmanship leaves a lot to be desired and I don't apologise for it because I concentrate my efforts in other areas of bowyering. We all have different skill sets.

       If we made a short list of things we do to gain energy and a list of things that cost energy we would find all of our designs are interpetations that attempt to maximise the good and minimise the bad by using tradeoffs. As we discover new sometimes small nuances about wood we are able to reduce the severity of a tradeoff to better favor a design element. The material we have chosen to work with has its own set of limitations that no matter how hard we try if we violate those limits we pay a price.
 

[avcase]

Steve,
I am really impressed that you figured out a way to bring this design principal to the self bow world.  It is especially challenging for a long draw length bow of moderate draw weight.  It seems such a design would be the exclusive domain of horn-wood-sinew composites or modern composites.  The Drake flight bows were like this with small bending areas right out of the fades, huge static recurves, and very fat force-draw curves.

I'd be curious to know how it shoots a flight-weight arrow?  I bet it is as smooth as can be.

Alan