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Pulled my cocobolo side out of the bender and disappointed to see that while the bend went very well (cutaway OM) the sides have that potator chip quality. The sides are thicknessed to .075 so not sure I can sand it all out. Thinking of trying to iron some of it with house iron. Any suggestions.

Why did this happen ? I very lightly spritzed the sides, wrapped them in kraft paper and heated to 350 degrees, shut off and then reheated again to 350 to set the bend. Sides were not high figure and pretty straight grain.

Thinking heat was too hight for colo ??? And perhpas didnt need any water as coco has oils? Really didnt saturate the sides, just barely covered surface on both sides.

Hey Zootman Bob - Will need a couple of new sides in colobolo. Can you ship this week ??

Hi Rich my friend!

I suspect that you have it right in what you said above. I am sorry that this happened to you bro.

Sounds like all the water wasn't driven out while 'cooking'.

I don't use any paper while bending. I also have a perforated top slat to aid in drying. I've never had an issue with any cocobolo, even the wildly figured and/or flatsawn sides, and find it the most stable of the woods I use.

To try to save these, try cooking them dry, at slightly lower temps.

Got quartersawn?

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Not sure that quartersawn is the issue here, although it could be. I would almost think these weren't held in tension enough during bending and holding, and finally cooling. Also, I've had weird things happen to sides where the grain was tighter or wider in places on the same piece, and the sections acted identically on both sides. That was weird, but it showed me that in those particular pieces, there were different amounts of stress in the different sections of grain width.
I also switched to using solid bending forms right after that, and haven't had issues since. I think that tends to help keep the wood from moving one way or the other during the process, so long as you have the top slat tensioned properly.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Rich;
Glue another set (double sides)of whatever woods you have and this will allow you to sand the Coco flat without destroying it!
Learning how to fix our mistakes & the weird stuff that wood & guitars throws are way is a never ending learning process!




Mike

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Mike Collins

Good point, Don. One thing to do when using a Fox type bender is let up the waist by about 3/16-1/4" after fully cranking it down, completing the bends of the bouts and fastening down the slats at their ends, and then cranking the waist back down. The helps to pull the wood and top slat down so there isn't a gap between the side and your slats. Another thing that can help is grabbing the end of the side with a wide jaw sheet metal plier and pulling out and down as you bend the bouts (may require a third hand). I haven't needed to do that, but I always raise and then reclamp the waist.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks to all for your input. I am going to combine some ideas here.

First, taking Grumpy's advice and combining with Todd's, will reheat at 320 degrees. Also using Howard's input will loosen the waste and retension, and make sure to pull the bottom down tight.

If all that fails I am going to experiment with the double side but I dont really see how that would help. Seems like I would still have to sand the ripples out and would result in the colo becoming a veneer. Not sure if that is really bad just different.

Just in case, Bob C is sending me a new set.

Well the saga continues. I reheated the side I had bent and left it in the form overvnight and no improvement.

Then I decided to bend the other side and didnt use any water at all. Also used lower heat, around 300 degerees at peak and no double heating. Same potato chip probem !!!!!

As the side was cooking I could hear sizzling. Is it possible the sides were green? Would the oils cooking provide the same sound ? Just cooked up a set of Mahogany sides and no probblem.

Well anyway, I am now going to play with the idea of making double sides from this set. Using Honduras Mahogany for inside laminate. Thinned to .04 and figuring when I am done I will end up with .11 and then sand the sides down to around .08 which may eliminate all the ripples and leaving .04 of the coco and .04 of the mahogany.

Waiting for second set of coco sides from uncle Bob in case the double side lamination doesnt work out for me.