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My current builds of cocobolo and ovangkol has some side ripple as you can see from the pics after I drew a soapstone straightedge around the sides. Obviously the visible soapstone rubbings show high spots. Mostly these are very small ripples and I canscrape them flat. However, I want to avoid these problems in future builds. Wondering whether I used too much moisture in bending or too much gobar pressure when gluing on back and sides. Any suggestions would be welcome. Thanks.

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Under Compensated Nut!

how are you bending your sides. machine? iron? other?

I'm using a fox bender with a heating blanket. I don't have a temperature monitor , just a controller. So amount of heat might be an issue?

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Under Compensated Nut!

How much water. I don't think you used excessive heat as the coco will darken quite a bit and give off a lot of burned black sap if over heated. I just dampen the coco a bit before bending. I have never bent ovangkol so don't know about it.

Fred

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Fred Tellier
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I always expect some "rippling" in the sides after bending. Some of it may disappear after a few days in the mold, but the rest will need to be sanded out. Lay a straightedge across the high spots to see how much material will need to be removed. Depending on how thick the sides are & how high the humps, you should be able to block sand the sides smooth.
I have been using Supersoft II for quite a while now... Much better results than with water.

I had ripples before finding a way to add tension to the bending process. Adding the tension essentially eliminated them.

I bend the waist first, but not all the way; I'll leave it so it's 1/2" or so from the form. Lower bout, upper bout, then finish the waist by setting it all the way. It pulls everything tight to the form.

I think I read about this method first from Lance, and then from Todd's bending videos on YouTube. Works like a charm. No ripples.

Thanks guys. James, that's the method I have used as well. I am using solid mold, but it is not the full width od the sides. Four pieces of 3/4 ply laminated together.

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Under Compensated Nut!

from what i can see is that you need better support. make a full width body insert for your fox. use a slat between the blanket and the wood and use springs to pull it down the sides of the upper and lower bouts. i put in about 3 to 5 degrees of draft on the bout ends to adjust for springback as well.