Making Bows from Billets Question

[Roy from Pa]

I have been building BBO bows for quite a few years now. I have always used 1/4 sawn billets which are 36" long, 2" wide and at least 1/2" thick. I Z-splice them together for my stave. I have made some sweet bows over the years. Only have had 2 blow up on the tree from a complete Osage failure. Now in the past 2 weeks, I have had two bows made from 1/4 sawn Osage billets, throw up a very thin crack along the outside edge of the limb, about 12 inches in from the tip. Never had that happen before.  

So my main question here is, is 1/4 sawn a good choice for BBO bows in a r/d design, or would flat sawn be a better choice. Sitting here thinking about this, seems to me that flat sawn might be a better choice over 1/4 sawn. Because when using 1/4 sawn, as you narrow the limbs from the flares out to the tips, you are cutting through every growth ring, leaving a possible weak spot along the edges of the limbs. Where as with flat sawn, you would have several consistent growth rings the whole width of the limb.  

Did I make any sense? LOL

[Diamondback59]

roy  thats the same stuff  ya had the other day  that blew up  ?  i relley wonder if ya have some wind checks in there ya cant see like i did  i scrap that lot of wood get some new stuff  and  ya id go flat sawen  hope ya have better luck this time brock

[Roy from Pa]

Ya Brock, same two bows. I was just looken for advise on 1/4 sawn compared to flat sawn. Ya mentioned wind checks in the other thread, what the heck are wind checks? LOL

But anyways, after thinking about how wood is sawn and how we make bows. I was just looking for input on 1/4 sawn compared to flat sawn. I bought the DVD by Dean Torges years ago and he suggests 1/4 sawn wood for BBO bows. Just starting to second guess him, that's all:)

Thanks, Roy

[Diamondback59]

roy  wind checks are  where the wood  has slight checks between the growth rings  i didnt even know about this stuff  i was up at dean marlows  farm  and we were lookin at some staves  dean showed me  what they look like  most the time u cant see em but  if there there  they seprate  between the growth rings   i agree with u  me i use the flat sawen and i havent had any plms so what works is what im gonna do  lol seems  the wind checks are mostly in  ill osage  or windy areas  from what i can tell brock

[Pat B]

Roy, you still have to consider the grain runoffs with hickory backinge, both on the back and alone each side.

[John Scifres]

My experience is that results are about even between the two.  I have pulled splinters from axial grain about as much as from growth rings.  Either way, you are violating fibers as you taper and expose yourself to splinters.  A particular piece of wood may do weird things though.  Really weak or thick earlywood may be a cause for concern when choosing 1/4 sawn.

The best choice is a nice long taper and low angles of violation in areas that bend a lot.

[No-sage]

I would use flat sawn if the wood had a lot of pins.

I like quarter sawn.  I've only had the problem you're describing when the grain curves out of the limb too severly.  Just like a run up in a board bow, you can have then, but if they're too severe, they can cause problems.

I'm not much of a believer in following the grain up the whole side of a bow.  If you were to take that to the extreme, you would never be able to cut in a handle or narrow the tips.  Every time you add these features, features of almost every bow made, you have to cut through the vertical grain.

[Dean Marlow]

Sounds more like a grain run off problem. I am not ecperienced a whole lot in glue up bows but it is really tough to follow the grain in boards sometimes. If you got an extra piece of that osage laying around try splitting it on one of the ends and see if it splits straight or runs off the sides. Dean