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What techniques are being used to copy the interior top bracing layout of a closed guitar box?

Some ideas I've got...

1) bright light inside-trace the shadows on the top, etc. (caution about heat buildup!)
2) styrofoam imprinting-taping several sections of 1/2" 3" X 12" or so styrofaom together (like Stew Mac's folding inspection mirror trick)unfold when inside guitar, and press up to bracing
3) getting brace angles-use something like a feeler gage nestled into intersection, tighten nut.

Need more input!

I have not had a heat build-up problem using a light. I use a kitchen under cabinet 12V halogen. the little round fixture Home Depoit sells. They come 3 to a package I just use one of the fixtures and move it around as needed. I turn down or off the shop lights. It only take about 10 min to trace. Easy to set-up and maintain centerline orientation.

Bandsaw guitar body lengthwise along sides, then measure BOTH top and back braces!

Magnets.

See the MIMF for details!

Magnets. Place a sheet of paper on the top of the guitar. Place a a couple of rare earth magnest inside the guitar that are flush against a brace. Place matching magnets on the top of the paper. Use a straight edge against the magnets on top and draw the line for the edge of the brace. Move the magnets around to get the edge of each of the other braces.

If I recall correctly, Mario did this and posted pictures of it. I look in the MIMF archive and didn't find it but they are so far behind updating that it could still be in the input queue.

[QUOTE=HankMauel] Bandsaw guitar body lengthwise along sides, then measure BOTH top and back braces! [/QUOTE]

Hank, I shoulda guessed you'd have a pretty direct route.

Thanks! I'll let you know how it turns out.

(BTW, I'm glad you responded, it's on e of your earlier guitars, I'll send it to yo uif I have any problems)

Thanks Mario, I can imagine it already. Yet another use for those wonderful magnets!

Terry,
You might think I'm being sarcastic, simply put your hand inside and let your fingers paint a picture.
You would be amazed how sensitive your fingertips are when it comes to perception and form!!
Walter

Terry...what's the Serial Number and date on the label? Model name? Who owns it (now)? I might be able to give you some insight from the original build sheet. If the label is missing, look inside with a mirror and the date I braced the top should be written near the soundhole/waist area, ahead of the upper X brace legs. Maybe send me a digital pic, if possible.

And...does it sound "THAT" good that you want to copy the bracing???

Hi Hank,

Please forgive the embarassment, I was only kidding. I am terribly sorry. If it was yours' I would've put an offer on it, rather than copy it.

Again, please forgive me

That's OK...now you can just go cut it in half like I first suggested!

[QUOTE=HankMauel] That's OK...now you can just go cut it in half like I first suggested! [/QUOTE]

Here's a successful suggestion I got from off line...

Cut a guitar shaped piece of white paper, tape it inside, cut out the soundhole for access of course. Break one and a half inches off a pencil and skin it down to the lead. Use it sideways to mark images of every brace, then take the refill out of a ball point pen, appropriate sized drill, etc., and punch holes through the bridge pin holes for another reference.

Take tinfoil and mold it around braces to get high and low measurements from the molds once removed from the guitar.

Align the final marking of the braces from tinfoil templates in problem areas where there isn't enough info marked with the pencil.

The new (Spring 2005) GAL mag has a similar article about using magnets for bridge plate outlines. Should work for braces as well I think. (See page 64).
Cogges

[QUOTE=Cogges] The new (Spring 2005) GAL mag has a similar article about using magnets for bridge plate outlines. Should work for braces as well I think. (See page 64).
Cogges[/QUOTE]

Some of us don't get that publication, is it similar to aforementioned magnet techniques, or different?

Thanks for the response