Selfbow Questions

[kctreeman]

I am getting some staves worked down to take to MOJAM to work on.  I have the osage staves roughed out to about floor tiller.  I want to back them. I am shooting for upper 50's to low 60's and the staves are cut to 58-62.  I have a  short 26-27 drawlength. My questions are:

1) Should I sinew now and tiller later or should I get it to a working weight and then add the sinew?

2) Same question as one but with bamboo.

3) How do you guys get the bamboo to fit the osage properly for a good glue line?

I have to go do the 4th picnic thing right now so I be checking in later.   Any help would be appreciated.

[Justin Falon]

If you use bamboo backing you can do it one of two ways in my exp.  You can flatten the bamboo, trace your bow pattern on it then cut it out and glue it to the osage slat.  Or, you can flatten the bamboo, glue it to your osage slat and trace your pattern on to the bottom of the osage and cut out with bandsaw.

You will get more opinions throughout the day.

Good luck!!

[Eric Krewson]

I flatten bamboo and osage on a belt sander. If you haven't done a bamboo backed osage bow you need to read up on it to get your bamboo properly flattened, thinned and tapered so you don't end up with an osage belly(very little osage) bamboo bow.

Tiller for the most part before you apply the sinew.

[Osagetree]

Never used bamboo, I do not see how you could use it on a osage stave where you have followed a growth ring. How could you get a proper glue line?

Bamboo is more suited to an osage slat that is planed flat on th back.

Never used sinew, but if I did, I would tiller first and retiller after curing.

[Minuteman]

Don't waste the backing if you have a good ring chased on osage. If you wanna tiller it at Mojam you won't have enough time for the sinew to cure properly before then anyway.
 As far as fitting the boo to the osage ,an electric planer or jointer makes short work of it. They'll make short work of yer fingers as well so be careful.
 Google "Bamboo backed osage bow "and see what ya come up with.

[NorthShoreLB]

Buying Torges video is a great investment if you plan to make backed bows

[kctreeman]

Thanks guys.  I think that I'll try the bamboo this weekend.  Is Smooth on a good choice for the glue.  I have quite a bit left over from building fiberglass bows.  Minuteman, how much drying time do you reccommend for the sinew?

[Walt Francis]

Like Manny suggested, buy Dean Torges video; It will save you a lot of headaches (and wood).  He does an excellent job explaining how and why to thin your bamboo and if not done correctly the bamboo will over power you osage.  I will give you one guess how I know    

I prefer Resorcinol(sp?) or Urac 185, but if the Smooth-On is not outdated it will work fine.

[Minuteman]

KCtree, I don't know how long to tell you I've never done it. I do know what other people who HAVE done it recommend though.
Well it depends on the glue used as well. If you use titebond 1,2 or 3 then yer gonna have a much faster dry time but you won't get the most out of the sinew. It won't shrink as much as it dries and the glue won't allow the sinew to stretch as much. (Also from others experience not my own) Hide glue or fish glue would be a better choice for sinew IMO and those kinda glues take a long time to cure properly like 3 or 4 months depending on humidity levels.Some times longer.
 If yer doing your first bow I would keep it simple and chase a ring for the back and learn to tiller before you put so much time into the sinew backing and then wreck the bow through inexperience. Just my 2cents.
 Have fun at Mojam, wish I could make it again this year but my good buddy and campin partner won't be going , and I got a pronghorn hunt to get ready for so ....
 Have a good time, you'll learn alot at the jam if you want to.
 Chris