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I finished lining a quilted mahogany J45 and noticed that there is a 50 cent sized flat spot on each upper bout on the top edge. It looks like the quilting there didn't bend when the rest of the wood did. The flatness is only at the edge and does not happen at the edge of the back. I hope the pictures convey the problem better than my description. It is so obvious on the pictures, but until I got the lining on, it just wasn't that obvious. I feel like an idiot for missing it, but would have posted the same question (just one step earlier).
So....obviously, when I rout for binding that flat spot will cause a deeper, flat area on the edge of the top, and there will be a big gap (or the binding will end up thin there).
I'm not sure if anything can be done at this point.
Thanks for looking. Beth

Here's my suggestion.

- Chisel out the linings up to an inch appart from the flat spot
- Back the inside of the side section with some veneer
- reinstall new lining
- sand to eliminate the flat spot

You will end up with some portion of the sides that are thin, but they will be reinforced with the veneer, so it won't be a problem.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Darn quilt.

That happened to me on my last quilt OM. I bent it by hand on a hot pipe.

I just sanded it out, knowing that even though the side would end up thin right there at the edge, it was attached to a pretty thick lining.

When I routed out for the binding, I could see how much was sanded away, it only ended up about half the thickness but really only at the edge.

The guitar's not had any problems as a result, maybe there's a better solution though.

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Old growth, shmold growth!

Me would remove about 10 or 11 of the curfed lining blocks.
Fabricate a solid block about an inch or so thick with the correct curve/
Steam the ribs edge up to bending temperature and camp in the solid curved piece.
After the rib takes the new set and has dried from the steam, band saw of the excess from the block and immediately
glue it into place.

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Audiences and dispensations on Thursdays ~ by appointment only.


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Yeah Filippo, I see a couple other ripples now too, but I do think those are safe to sand. I'm going to think about Alain and Padma's ideas. I'm leaning toward steaming it into shape. Should I use veneer softener first?

If it were mine I would do as Padma advises or start over. It is not an easy solution even for a pro... getting the correct curve carved into a clamp-able caul, then steaming evenly in the right spots and getting it clamped in time will require some skill and luck.

Welcome to the world of bending figured woods!

If you're going to start over, might as well try first.

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Old growth, shmold growth!

Put a scoop in there it's just about the right spot if thats the top, Oh no wait that would make it a lefty. You might be able to cut a piece of wood with a little under the proper shape, slip it inside and hit it with a hand iron with some wet 100% cotton on tthe wood

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Michael F Smith
Goat Rock Ukulele
http://goatrockukulele.com

I like Padma's, too. Or inside-out:
Convert the kerfing there to individual blocks by sawing the continuous wood (or completely remove the kerfing there.)
Bend up some lining strips to reinforce the inside.
Steam/soften the siding / place in the body mold.
Glue/laminate the lining strips to the inside/kerfing, clamped to the outside mold to define shape.

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David Malicky

One thing to watch out for with steam on figured wood is wood fibers "delaminating" (if I can say so). This is why bending with steam is not used for guitar sides. I know I have experienced wood fibres "popping up" when bending on a pipe and using too much water (the wood was quilted mahogany).

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I guess I could try a localized solution first....take out just a segment of lining on the top edge, see if I can heat it against a curved caul. If that doesn't work, Todd's suggestion of removing top and back lining. If I do that much lining removal on quilted wood, I'm worried about damaging the sides doing the removal. How would you guys remove the lining? I could use a coping saw and then sand residue off. I don't know how they would chisel off....that would be simplest, but may be difficult. I used Titebond II.
I have a curling iron with a rheostat on it that has about a 1.5" diameter.....think that would work for a pipe?

Not sure if it will end in disaster. I had the SAME thing happen to me with some Uke sides. I gave up on each one. Eventually used SS II and problem went did not show up (new sides). If you imagine a arc through that, you can see how thin it will get if you just sand.

You could try ungluing everything. Spraying on supersoft. Let set for a day (wrapped). Then putting back in the bender. That would be my approach.

Well Beth, it seems the general consensus is
...remove the linings in the area and rebend with some sort of culls/mold.

Several variations on this approach have been presented.

Chose the one that tickles your fancy.

Although a pain in the ask me no questions....me personally do not see it as a difficult fix. Think it through with pictures in your minds eye of every step ~ over and over again until all of a sudden the lights go on and you simply "just do it"

It will be fine.

The lesson here is to figure out just what caused it and then "sin no more."


blessings as always.
Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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Too true! I used supersoft, and bent according to Todd's sandwich technique, but I think this quilt just has a tricky area. If I'd seen it before lining...it would have been no big. Won't happen again!
I'll let everyone know how it goes, but probably won't be able to do it until after an upcoming trip to Maui!!!! I hope to see some great ukes there, and maybe try a few:)
Thanks everyone!!!!!

A trip to Maui should take a bit of the sting out! Have a great time, Beth!

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Beth, you could use a good hair dryer to heat up the lining to remove it. Do it in sections. Quick passes. Once u get some lifted it goes pretty fast. The glue will release once it gets warm. Hot is not necessary.

There is no need for saws here!!

Mike

Thanks Mike. I thought it might be harder to remove sections because of it being reversed kerf lining. I'll try the heat and lift method.

If I were going to try to bend it out, I'd use a pipe. But I think it'll sand to a fair curve pretty easily. Reinforce inside with some layers of veneer, as has been suggested. It's not going to be a disaster at all. Just a temporary setback and a bit of a pain. You'll get it worked out.
Please show us a picture of your "fix" when you've got it curved to your satisfaction. I think it will encourage a lot of new builders.
Patrick

Agreed. Sand it as close to curved as you can without getting scary thin. When you cut the binding channels, you could sand them to make the curve perfect when looking from the top. The bindings will be thinner at some points but it shouldn't be bad. Most likely, nobody will ever know or notice. Unless you are selling this guitar for several thousand, you might cause more problems than you solve by removing the linings and trying to perfect the bend.

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http://www.CostaGuitars.com
PMoMC

Beth, do you mind me asking how thick those sides are? Seem a bit thicker than anything I've bent.

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Thank You and Best To All

0.085". The thickness John Mayes lists in his bending tutorial (you can print it from his website, I think). They bent really well (except for that one facet on each side). If they are a little thick, that will work in my favor with this problem

Thanks Beth,

That's what I'm bending at too. Looked thicker in the pic for some reason.

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Thank You and Best To All

Beth- when in Maui check out "Mamas Fish House" , great local stuff for a once in a lifetime journey. And snorkeling is great in many areas, ask in any of the many shops for the good stuff in the area you're staying.

Thanks for the tip, William! Will find it . Thought we might just rent snorkel gear for the whole week an toddle around the island.

Better option for snorkel gear is to stop at the Maui Costco and buy your own set. Cheaper than renting for the week, excellent gear, and only your lips will touch it.

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Doug

Don't let fear or common sense stop you from trying to build something