A more-or-less copy of a Martin OM

[Diane Kauffmds]

I guess I now I can't deny responsibility.

Okay, now I'm jealous. I really wanted to do this in my OM, but I don't know how. I settled for signing the bridge plate, then making the label.

[MaineGeezer]

You can get letter and number stamps from McMaster-Carr, among other places:
http://www.mcmaster.com/#metal-stamps/=vowbzt

The ones I used are 3/32" high. There is a natural tendency to think one needs a larger size than one actually wants. 3/32" is pretty good. You might prefer 1/8" for wood stamping. I got the 3/32" stamps for stamping metal.

Lining up the letters/numbers when stamping is a bit of a trick. It helps to have a ledge to line up the stamps on, and to stamp right-to-left (assuming one is right-handed) so it's easier to see the previously-stamped character.

[Diane Kauffmds]

I'll check them out. Thanks

[MaineGeezer]

It's starting to look more like a guitar! The back is a lot flatter than it's supposed to be. Even after re-humidifying, it hasn't fully recovered the curvature I thought I built into it. I remain puzzled.

[Diane Kauffmds]

I'm assuming that the very end of the back braces haven't detached?

Just a suggestion. Have you tried keeping it in the mold while humidifying? As much support as the back gives to the sides, I noticed when I was building, that the box didn't retain it's shape completely, unless I put it back into the mold until the top was attached. I know the braces shape the back, but keeping it in the mold until attaching the top, can't hurt.

BTW, I had the same problem with the top. It recovered a little, but not completely. However, it didn't affect the fit of the top to the box, or the sound.

[MaineGeezer]

The back was nearly flat when I glued it on, and the sides were in the mold at the time, so I think I've got what I've got. I currently have the back+sides assembly in a case with a humidifier. I'll see what happens.

[Diane Kauffmds]

The back was nearly flat when I glued it on, and the sides were in the mold at the time, so I think I've got what I've got. I currently have the back+sides assembly in a case with a humidifier. I'll see what happens.

I think you've done all you can Steve.

[MaineGeezer]

Today I glued on the top. In the process of gluing it on and applying clamps, one of the back braces split. It is not at all clear why it split. I don't understand how clamping the top could apply pressure in such a way that one of the back braces would split, but somehow I managed it.

SO...I'm trying to glue it back together. At least it was the brace just back of the soundhole, so access is as good as ils possible to have. Which, for a guy with big hands, is still not very good. I got some hot hide glue into the crack -- I hope -- and put a couple of jackscrews between the brace and the guitar top, with an external clamp to hold the top and bottom together against the force of the jackscrews. The repair looks terrible. Maybe if I sand it when the glue is hard it will look a little better.

[johnnparchem]

The guitar looks really good. I am surprised that a back brace spit. How did you clamp on the top?

When you clamped on the top where was the non top side of the clamp?

[MaineGeezer]

The guitar was sitting on a board with padding around the perimeter of the guitar so (in theory) the guitar would touch only on the padding. The clamps went under the board, effectively clamping the guitar to the board. Here's a picture of the back being glued on -- the top was done the same way.

Apparently the padding wasn't thick enough, so the back got pressed against the board which therefore pressed up in the center of the brace.

It's particularly odd because, as you are aware if you've been following this rambling account, the back ended up nearly flat and has very little curvature to it, significantly less than it was intended to have. Nevertheless, apparently it was enough so the back made contact during the clamping process.
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