I have been away from bow building for a few months due to hunting season, moving to a new house, and the holidays. Now I am back and more excited than ever. I have started a new osage selfbow that I plan on backing with sinew. I have just read Hunting the osage bow and tried to follow Dean's design. The stave had a small amount of reflex when I started, but after cutting out the bow on the band saw, I have hit a problem. One limb is straight, and the other has reflexed quite a bit. Since I am going to sinew back it, should I straighten out the reflexed limb, or should I try to reflex the straight limb to match it? I have only used a heat gun to do minor limb adjustments. Can I use it, or will I have to use heat?
(http://i141.photobucket.com/albums/r55/clintanders/SDC10312.jpg)
(http://i141.photobucket.com/albums/r55/clintanders/SDC10317.jpg)
Here, my little helper is looking over the problem.
(http://i141.photobucket.com/albums/r55/clintanders/SDC10320.jpg)
It will be a shame to cover up this bow with sinew. The back has some amazing color. The limbs are dark orange and the handle area is light yellow. At first, I thought I had messed up and skipped a growth ring when chasing the back.
(http://i141.photobucket.com/albums/r55/clintanders/SDC10318.jpg)
If it was me, I would take out some of that reflex on one limb (some) and put some in on the other limb.
Do you think I can heat gun it, or will I need to use steam?
You can and should use heat gun. IMO.
But you might have to get the stave more floor tillered to do it. Just to get some more material off.
Thanks for the advice. I might try to heat bend some of it out today if I have the time.
If you have a clean ring on the back of it, why bother with sinue.
Looks like the reflex begins at a knot or some other inperfection on that limb (photo 1 &2). Could that creat a problem. Just asking, havn't a clue myself :)
Good long heat soak at modest temp on big moves like that, to avoid scourching the wood, the back ring in particular. It helps it have it closer to floor tiller stage. Some kind of caul or form helps a bunch too, especially when you need to move a limb to line up the string in the handle. I shield the area I'm working on to hold the heat (with an aluminum pie plate or whatever, sometimes w/ a towel on top to insulate). I'm liable to leave heat blowing under the "tent" for 10 or 15 minutes. Be mindful to not let it get too hot. It will get soft enough you can move it around with relatively little clamp pressure. Two or more corrections on big work.
(http://home.comcast.net/~dcm4/gg1.JPG)
(http://home.comcast.net/~dcm4/gg4.JPG)
(http://home.comcast.net/~dcm4/gg6.JPG)
Leave the nocks wide and handle wide if you can. I would use dry heat to add some reflex to the other limb. I'd add 2 in. I would bring the other down to 2 in. I grease the back of the bow and heat only the belly. I'd make adjustments slowly clamping as I go along. Jawge
After using the dry heat, be sure and wait a few days before you go trying to bend the limbs!
QuoteOriginally posted by Osagetree:
After using the dry heat, be sure and wait a few days before you go trying to bend the limbs!
Thanks for the tip. I did use a little dry heat and some veg. oil on it today. I tried to straighten it out a little. Here is what I did to it.
(http://i141.photobucket.com/albums/r55/clintanders/SDC10331.jpg)
How long is your stave? If it is over 60" sinew is not a good option, it adds too much weight to the limb. Sinew is better used in a short bow to hold it together when the bow is drawn to longer draw lengths.
QuoteOriginally posted by Eric Krewson:
How long is your stave? If it is over 60" sinew is not a good option, it adds too much weight to the limb. Sinew is better used in a short bow to hold it together when the bow is drawn to longer draw lengths.
It is right at 60"long. The goal is 60lbs @ 28". I made some more heat adjustments and now the string is centered with the handle. I plan on getting a little bend out of the limbs and then trying the sinew. I am also working a shorter bow. I think it is around 55" long.