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Looking for a few tips to allow me more successful bending these woods on a Fox style bender without cracking. I'm thinning to around 0.070 or a bit thinner, have emulated John Hall's video and used Windex or Super Soft. The venetian bend on cut-aways seems to be the usual site, but sometimes the waist on an OM joins in. Are there particular temps recommended? How fast/slow should the bending process proceed? Sapele seems to be the leading "cracker," but I manage with other woods as well.

Thanks for all who chime in!

I bend on a pipe but I can confirm that Sapele can be difficult. Even going slowly on the pipe where I can feel the wood’s readiness to bend sometimes gets me cracks in Sapele. A strong vocabulary doesn’t fix the crack but does release some of the frustration. Sides cut from the same board seem to have the same behavior indicating that runout can be an issue. Of course, heavy figure means there’s always runout somewhere. Quartersawn Sapele is easy to get at many lumber yards, so if you cut your own sides, replacing a split piece doesn’t have to be that expensive and you might find a board that’s more amenable to bending than the one you have.

I prefer Venetian cutaways—it’s just personal preference. But, when I split the side bending it, that one becomes a Florentine.

Difficulties aside, I’ve always been pleased with the sound of the Sapele guitars I have made.

I’ve cracked so many sides trying to make Venetians, I don’t even try anymore. I just go straight to Florentines. I think I was successful 3 times.

most people crack because of not using the heat properly. I have been bending for shy of 30 years . Most use way more heat than needed and bend before the wood is ready. You should be done within 4 minutes of turning the bender on. If you are cracking sides you obviously are not doing it correctly.
I started to use the weights a few years ago and this will greatly increase your bending success. 285F is about the perfect temp for most woods. Also bend in the proper order
Lower bout first usually at 220F
waist at 240/250F then the cutaway and use wet paper on top and bottom of the wood. I use windex with ammonia D
or a solution of ammonia about 5% is plenty.

I also am about .075 in on the side no need to be thinner.

if you wait too long to bend the cell is setting and won't collapse , too soon the cell is not pliable and will separate. I have plenty of vids on this on you tube bending library

If your using a heat blanket if isn't a 5 watts per sq in they loose too much heat upon contact and take too long to heat the wood causing cracking.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it