I have been making all types of bows for some time but for whatever reason, I had not backed a bow with hickory until recently and had a surprise. I backed an Ipe stave with a nice clean,well seasoned, edge-grained piece of hickory milled to 1.5 X 3/16. I thought it might be wise to taper each limb like I do with bamboo. At the point where i left floor tillering to string the bow, the hickory lam broke on the edge of the limb. So my questions are:
1. Was this a rare fluke?
2. Would I have been better off to reduce the thickness to 1/16-1/8" over all and not tapered?
Anyway,I removed the hickory and applied bamboo to finish the bow but still embarrassed about the incident. Any thoughts for the Old Timer?
Do you have pics of the backing that broke? I have built quite a few hickory backed bows over the years and the only back failure I ever had was from a backing strip that was infected with fungi. Even the backing strips with bad run offs never failed.
I would saw backing strips to about 3/16 then dress them down to 1/8". I never tapered backing strips but that shouldn't matter that much.
Did you round the corners off? I've never made a bow without a hickory backing (I know, I need to branch out a bit) and I've only had one fail and one raise a splinter. The failure happened when I didn't round off the corners and split at a pin knot. The splinter happened when I did round the corner but left a tool mark by mistake.
Hickory in my experience is almost bomb proof. I run my backings 1/8th -3/16th.
I think it was just a fluke as well, Si. I love hickory as a backing and have only had one raise a splinter. It was on a thin ringed bias sawn heartwood board. I make mine 1/8" and flatten the edges a bit with a rasp before rounding them with sandpaper. I've only tapered one on a tri-lam recurve, taking it down to 1/16" at the tips.
Thanks guys,
I thought about those edges too and should have rounded them sooner.
Si
As I work a bow I keep all edges rounded, back and belly. Its only a few extra scrapes but is worth a bow. d;^)