Hey,
New to this so unsure as to where to post this. I was tryin to make a short bow out of birch. It was a very young tree, only 4 inches throw at the base, I cut it down in mid winter and it has been dryin for about 2 years now. The bow I tried to make was only 20” tip to tip. When I was tilling it I only draw it to a 7” draw. This bow I was planning on using for bow on a small crossbow. At this size it had a draw weight of around 25, 30 pounds. While I was tillering the bow, wood started to lift off of the back of it about 2 inches down from one tip. So I though since I had just taken the bark off of it the sapwood was no good. Then I took off a few rings of wood, now it is only 13 and ¾”. I nicked through one ring to many so I had to take it down more then I was planning on. That’s why it got so short. But that worked out a little better I guess, since now it is goin to be shorter for a crossbow pistol. Now it is about a 5 to 10 pound draw at 4 inches. This time at the handle on the back it looks like it is starting to lift again. Why is this happening? Anyone have any ideas? Is the wood closer to the bark failin under tensions? Did I not let it age long enough? I life high up on the mountains (around 3000 ft) in the interer of BC, Canada, would this affect the agin of the wood in any way? Is it just the type of birch I’m using, not sure what type it is but it’s the type that the natives used to make their birch bark canoes out of. Also on the belly I noticed that there was some fine lines cutting across the grain after tillering, what are these lines called, that is if they have a name at all? Does this mean that the wood is also failing under compression as well? I was planning on baking this bow with sinew and putting cow horn on the belly. Is this still possible or will the wooden core just fail on me and waste me time and sinew and horn? I was planning on wraping some sinew around the spot where it was starting to lift before I backed it and put before I put the horn on the belly. I was tryin to use wood that is around me but don’t have much around here that I know can be used to make a good bow, I have birch, some mountain ash but haven’t found a big enough tree all I have found have been more like bushes, mountain vine maple, and some juniper. Would I be better off using some mountain vine maple instead? New at makin bows, have always wanted to do it and have tried over the years but haven’t had that many that have worked to well or lasted that long. Thanks for any help in advanced.