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Need help bending Sapele
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Author:  Dave Rector [ Sat May 14, 2005 9:46 am ]
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I am building a prototype guitar based on an old Stella type that Byron Berline gave me. I decided to use a cheap set of Sapele from LMI since it won't be for sale and I thought it would approximate what it would sound like in Mahogany.

When I bent the first side it broke like a piece of glass or something. I had thinned it to .075 and misted it with water. I got the heat up to about 240 or so before starting any of the bends. It broke in the waist bend and then broke 4 or 5 times in the upper bout bend.

Anyone know what the heck I did wrong? I've used Sapele one time before and don't remember having this kind of problem. Could it have just been improperly sawn wood? LMI is usually a good source.

Any hints, suggestions or previous experinces would be appreciated.
Author:  Pwoolson [ Sat May 14, 2005 10:20 am ]
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The only red flag I can think of is your temperature. I bend no lower than 300? and sometimes 325? depending on the wood. Did you let the wood get hot before you started the bend? That's best to do but if you let it sit too long you'll loose the moisture and it becomes brittle. That's all I can offer.
Author:  John Mayes [ Sat May 14, 2005 11:28 am ]
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Dave,

Your more than welcome to come to my shop some time and we can bend
side together and see if we can't iron out the problems your having.
Author:  Dave Rector [ Sat May 14, 2005 12:19 pm ]
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Thanks for the advice Paul. There was plenty of steam coming off the wood so I assumed it was hot enough. Maybe I was wrong. Or maybe I didn't use enough water and it dried out. It did seem kind of dry and brittle.

John, thanks for the kind offer! I might have to take you up on that when I get another set to bend. I just ordered one set since this is a proto. BTW, did you move from your location out by the lake, your address says Moore now instead of Norman?
Author:  John Mayes [ Sat May 14, 2005 1:21 pm ]
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[QUOTE=Dave Rector]John, thanks for the kind offer! I might have to
take you up on that when I get another set to bend. I just ordered one set
since this is a proto. BTW, did you move from your location out by the
lake, your address says Moore now instead of Norman?[/QUOTE]

Yep I moved. I'm in Moore now. And if you got the 2nd side (I'm
guessing the sapele broke on the first side.) we can bend it and see if
everything is kosher and you can see if it all looks cool, and maybe pick
up a pointer or two. If that would help I'd be glad to do it.

Author:  Dave Rector [ Sat May 14, 2005 11:40 pm ]
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Unfortunately, I broke the second side as well. I thought since I no longer had a bookmatched set anyway...

On the second side I added considerable more water and cranked the heat and didn't get as bad a break, but it did still break.

Anyone know where I can get a set of Sapele sides only?

P.S. John, I may still call you as soon as I get some new sides.
Author:  Don Williams [ Sat May 14, 2005 11:51 pm ]
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Steam isn't a good indicator of how hot you have it. The steam aids in softening the wood, but the heat is the real key. Paul's temp numbers are right on. You need it that hot to allow the wood fibers to plasticize.
Author:  Pwoolson [ Sun May 15, 2005 12:12 am ]
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Dave, check with Allied, they sell the sides and backs seperately. If however this is a prototype for a mahogany guitar, wouldn't you be better off, both soundwise and financially, to build it from mahogany. I've seen mahog sets for $30. Might be worth looking into.
Author:  Dave Rector [ Sun May 15, 2005 12:30 am ]
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Thanks Don! I'll pay more attention to the heat next time. I thought 250 degrees would be hot enough to start the bending, wrong again.

Paul, you're right, it would have been better to make it from Mahogany. I was just trying to save a few bucks and basically see whether I liked the shape and feel of it. Might have to rethink it.

I checked Allied's web page and they don't offer Sapele.
Maybe I'll just get some Mahogany ans start over. That Sapele back sure looks nice though.
Author:  John Mayes [ Sun May 15, 2005 1:03 am ]
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[QUOTE=Dave Rector] Thanks Don! I'll pay more attention to the heat
next time. I thought 250 degrees would be hot enough to start the
bending, wrong again. [/QUOTE]

250 is plenty hot to start bending so long as the heat is all the way
through and even. I start it at 225-240 and I have not broke a side in
about 4 years.
Author:  John Kinnaird [ Sun May 15, 2005 1:45 am ]
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I personally use higher temps than John M. Especially if bending a cutaway, especially if its figured.

I don't try to start bending until the water has boiled away and the temp is allowed to start rising above the water's boiling point.
Author:  Roy O [ Sun May 15, 2005 2:05 am ]
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[QUOTE=Dave Rector] That Sapele back sure looks nice though.[/QUOTE]

A guitar back is enough wood to make the back and sides for a tenor ukulele. This would give you a chance to try bending the wood again in addition to making a cool little instrument. Or if you don't want to do that you can always send the wood to me.
Author:  Mario [ Sun May 15, 2005 2:36 am ]
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Keep in mind that internal stress can be present in any piece of wood, and be undetectable for the most part. You may have simply run across one of these. Don't always blame yourself when you snap a piece.
Author:  Dave Rector [ Sun May 15, 2005 3:28 am ]
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[QUOTE=Mario] Keep in mind that internal stress can be present in any piece of wood, and be undetectable for the most part. You may have simply run across one of these. Don't always blame yourself when you snap a piece.[/QUOTE]

Thanks Mario!

I did notice that this piece was very stiff even after being thicknessed down to .075" My instinct told me to go thinner or it would never bend. But I need something left to work with, so I tried it at that thickness.

The last time I bent Sapele I has a little separation on the grain on the upper bout, but nothing I couldn't fix. This time it just snapped. They weren't very nice looking sides anyway.

Now I'm thinking of just cutting up some sides out of some Mahogany I have laying around here. I just want to get it put together so I can see if I like the shape, feel, etc. Then I can build another one out of something nicer.

Thanks to everyone for all the comments!
Author:  L. Presnall [ Sun May 15, 2005 5:30 am ]
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Dave, try Vikwood out in Wisconsin...I've ordered just sides from them before...nice guys, great service and great wood...prices are good too!

Larry
Author:  L. Presnall [ Sun May 15, 2005 5:34 am ]
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Now I'm afraid to bend the quilted Sapele I got from Z....if the regular Sapele is that hard the stuff I got must be times 10! Is the idea more or less H2O with figured wood? And spritz or soak? Or just see if Uri Geller can bend it like those spoons he was always dinking with?

Larry
Author:  Dave Rector [ Sun May 15, 2005 5:44 am ]
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I wouldn't be afraid of it Larry. Just be careful with it and make sure you get it good and hot before attempting to bend it.

Like I said earlier, the last Sapele I bent was really easy. It bent almost like rubber. This one wouldn't give though.
Author:  Skip Beach [ Sun May 15, 2005 9:32 am ]
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Hi,
A few weeks ago I bent two LMI sapele sides & luckily had no problems using a Fox-type, lightbulb powered bender. The waist was quite tight too on this particular design. I spritzed each side well with a mister, wrapped it in aluminum foil & waited until the sizzle sounded about right when I spit on the steel strap. Who needs a stinkin' thermometer?

I bent very slowly, taking about 15 to 20 minutes to complete bending each side - as a safety precaution against breakage. I figure if 10 extra minutes is wasted at this point it's better than wasting time & money on replacing a side after breaking one.

I suspect that your problem was indeed just a funky piece of sapele. Better luck in the future!

Skip
Author:  Dave Rector [ Sun May 15, 2005 2:19 pm ]
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Yeah, I think I'll call LMI in the morning and see if they will give me some kind of deal on a new set of sides. I'm not convinced it was all my fault.

If they won't make me a deal I'll just have to buy another set.
Author:  Dave Rector [ Tue May 17, 2005 12:19 am ]
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I called LMI and they said they couldn't do anything for me. They said if I had sent the sides back before bending they would have given me a new set. Of course, I didn't know there was a problem till I had already thinned them and tried to bend one. Oh well.

They are going to sell me a set of sides only. That should get me started again. Guess I could work on one of the 3 or 4 others I have in various stages of completion until me sides get her.

P.S. I think I'm gonna order a couple of heat blankets and try doing it the way John does. I think it is taking my blanket entirely too long to heat up and the wood is drying out while it is getting hot.
Author:  LanceK [ Tue May 17, 2005 12:43 am ]
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Dave -
I dont use a thermometer - cuz I dont have one BUT - I use a Fox-Hall Bender and one blanket - I mist my sides, fold them in foil, then place them in the bender - kick on blanket on full blast, when the hear the water sizzling I bend the waist all but 1/2", then the lower bouts, then the upper, then I tighten the waist down, Ive never broke a side in the bender - except for my very first try using lighbulbs. Ive bent ziricote, cocobolo, rosewood, mahogany, Black Acacia, PauFerro - etc all with sucess.
Author:  Dave Rector [ Tue May 17, 2005 3:16 am ]
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Thanks Lance! That's pretty much how I do it as well. I've even bent a set of Sapele once with a cutaway and it didn't break. This one was a bear though.

I'll just get another set of sides and try again.

Thanks for everyone's input!
Author:  Dave Rector [ Tue May 17, 2005 3:43 pm ]
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Thanks Michael! But alas, I've already order another set from LMI. They were only $17.00, so it didn't hurt too bad.

I also ordered a couple of 5W PSI heat blankets so I can get more heat and get it much faster. Turns out my old heat blanket was a 2.5W and man is it slow to heat up.

I'll get them bent one way or the other
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