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cupped sides.
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10102&t=11092
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Author:  gratay [ Mon Feb 26, 2007 7:56 am ]
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After I took my sides off my form I have noticed a fair amount of rippling across the sides particularly just either side of the waists...

I couldn't get hold of any spring-steel (although next time I will use) so i used aluminium flashing...I figure maybe because the flashing doesn't offer any stiffness across the side being maybe one of the reasons..
Or maybe to much water....which the rosewood side was sprayed liberally then wrapped in alfoil..?

Does anyone have any ideas as to how to possibly get this out without sanding it flat as there would be 1-2mm difference in the peaks and valleys, so sanding would make the sides to thin i feel.....
and would the support strips on the side pull the sides out a little straighter when they are glued in?

thanks for any advice
Grant

Author:  Martin Turner [ Mon Feb 26, 2007 9:12 am ]
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Grant,

The bending iron is sitting in the workshop waiting to be fired up. Just let me know when you're popping around

Author:  KiwiCraig [ Mon Feb 26, 2007 9:48 am ]
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Hi Grant,
           I think too much water may be the culprit ,although some builders soak their sides in a tub for 1/4 hour or so and don't report rippling . I've just read The making of Claptons guitar . Wayne Henderson (the builder ) soaked his Braz. and is a believer in that method . On the other hand ,I understand Taylor bend their sides dry. I'm not really sure which is the better way to go . Others say oily woods don't need water (rosewoods ) whereas mahogany needs a little .Sorry this isn't much help. I hope others will chime in here and tell of what works for them.
It has always been an issue , whether to soak or spritz,,,,or go dry.

I have found it very difficult to remove the ripples . I've tryed the hot pipe afterwards , but didn't improve much . Leaving the sides a little thicker ,so you have got extra wood to sand flat is one solution . Puting it back in the bender for a dry cycle may help a little too.

Side braces don't help much either . Wish I could give you the magical solution mate . Maybe others can !!!

My sides on my latest ,(Myrtlewood) ,have no ripples at all!
Mahogany is known for the ripple affect.
I wrapped my Myrtle sides in foil , which maybe the answer .Traps the moisture in there a little longer while the heat gets up to bending temperature.

Cheers, Craig


        Lawrence of Australia

Author:  Dave Rector [ Mon Feb 26, 2007 10:49 am ]
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Grant, I have a set of macassar ebony sides on my bench right now that did the same thing. I bent them in the Fox bender and they came out wavy across the side and also had some faceting on the upper bout area.

I tried getting them straightened out on a hot pipe and managed to remove nearly all of the faceting but the ripples seem to be there for good. Oh yeah, I also tried making an inside caul that fit my mold and clamped them in the mold with the caul and a heat blanket. That didn't remove the ripples either.

I called Uncle Bob (aka Zootman Bob) this morning and purchased another set of sides. Hope you have better luck than I did.....

Author:  Bob Long [ Mon Feb 26, 2007 12:38 pm ]
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[QUOTE=gratay] would the support strips on the side pull the sides out a
little straighter when they are glued in?
[/QUOTE]

Grant, I've straighten out sides by beefing-up the strips. What I've done
is, clamp various thicknesses of brace material across the sides to find
out how small the brace can be and still be able to hold the side flat. A
piece of spruce 1/4" by 1/4" should bend the side quite a bit. If you do
this, I'd recommend puting them all the way across the side, and then
taper the ends so they are just as wide as the lining.

Long

Author:  Bill Bergman [ Mon Feb 26, 2007 1:14 pm ]
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I had a solid inside 1/2 mold. I used an old clothes iron that was heated on a stove and I pressed the side against the mold. Don't get the iron too hot, or you'll char the wood. If you do not have such a mold, it is probably not worth making one to salvage the sides.

Author:  SimonF [ Mon Feb 26, 2007 3:25 pm ]
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Grant,
Very early on, I discovered the advantage with bending with thinner sides.
I had a very bad experience with Malaysian Blackwood. The sides were
not thick enough to make them level - the "waves" were that bad.

I have since bent a number of very difficult woods (ebonies, etc...) and
always have my sides turn out perfect.

I thin my sides down to 0.070" or slightly above. Since they bend so well
at this thickness, you don't remove extra wood trying to make them level.

--
Simon

Author:  TonyKarol [ Tue Feb 27, 2007 1:33 am ]
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I have added extra cross bars to most of my forms right around the waist area, and this seems to help a lot. I did have one set of quilted sapele go cupped either side of the waist, and a couple 1/4 by 3/8 triangulated spanish cedar side braces fixed that but good !!! The extra weight is really nothing from these.

Author:  gratay [ Tue Feb 27, 2007 8:36 pm ]
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thanks guys for your experiences....

Craig.....I was thinking a dry cycle could be worth a shot as well. and they were wrapped in foil also....could be to much water issue.?

Bob....beefing up the strips sounds like the go and the length of the sides sounds like a good idea to me.

simon ....the first side was around .090 which was hard to bend and i thought the to thick factor may be the reason..But the second side i went down to .080 which was easier to bend but had the same result...which makes me think to much moisture.?

tony.....my bending form is solid ...but thats the spot.either side of the waist...and spanish cedar is a good tip for the weight factor of the beefy strips..

cheers guys

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