excessive sanding heat?

[okiecountryboy]

Does excessive machine sanding cause wood cristalization with overheating? I snapped another redoak bb. Did not shave, all wood reduction was done by a mouse sander. It snapped at the bottom of the fade. I was quite shocked.

Any input?
bout done with BB's. This one was for someone close to me, really let down to say the least...

Thanks

Ron

[half eye]

Can't say I've had any heat problems when I use my belt sander. If you are getting that kind of heat the wood will show heat or burn discoloration. I use 40 grit bonded belts on my sander and light pressure.....the problem I run into by using the sander is doing a "roller-coaster" by using the drum end of the belt (that will make real subtle hinges if you dont notice it.) If you notice that condition before you pull the bow.....I make sure the belly is flat by using 40 grit glued to a heavy block of plate steel and get everything flat before I pull the bow. Just my experience, for what ever it's worth.
Rich

[okiecountryboy]

thanks Rich
The only reason i asked is that i noticed what seemed to look like crystalization at the break.

Thanks
Ron

[aznboi3644]

what you see is probably chrysals...if it looks like a squiggly line than it is collapsed cells.

[okiecountryboy]

Hey y'all
Has anyone ever tried gluing a break together? I know, probably a dumb question, but still learning. Maybe 5 min epoxy?
Ron

[Pat B]

It really depends on the break. The glued area will probably be stiffer than the rest and may cause a hinge elsewhere. Probably best to start a new bow instead of beating a dead horse.
  Is there a reason you are tillering with a sander? Once I hit floor tiller I use only a rasp and scraper but mostly the scraper. Trying to rush will always get you in trouble. I've been building wood bows for almost 25 years and when I try to rush it ends up biting me. 
  If the the cracks are cross grain on the belly they are chrysals and your limb is bending too much at that point. I doubt the sander is causing it. Heat treated belly are stronger in compression anyway.

[venisonburger]

I have to agree with Pat, unless you are impatient I wouldn't use a sander, especially if you are new to bow building. hand tools are the way to go, slow down and take time, even if it takes you a month to finish your bow at least you'll have a good bow. Theres lots of info on board bows on this site, do some reading and ask lots of questions.
VB

[okiecountryboy]

Thanks
I was rushing.(had reasons) I also noticed some twisting in the limbs when pulled, probably from dif in belly thickness from side to side. I guess I'll invest in a sure form and a scraper.
Thanks for the help

Ron

[bubby]

I do all my scraping with a painters 5 way tool, inexpensive and I just use a file to keep the flat edge sharp