Clint, the link worked great, thanks. Great information.
So, here's what I tried yesterday, with fairly good results. I'm trying to copy, as close as possible, a 1931 OM-28. I taped
a flexible fabric-type tape measure onto the side of the OM. Starting exactly at the end pin joint and going around to the
heel. I then took a piece of sturdy cardboard and started with a vertical line as my end point for the side on the bottom
of the guitar. I took measurements of the sides every 2 inches and transferred them to the cardboard. After a while, I had
an exact copy of the side, length, height etc. I have found that no two old Martin's are exactly the same but this
is a good place to start. I'm going to either transfer that cardboard copy to perspex or strengthen the back of it with poster paper and work with it as is. Probably better to use perspex as it's more stable, we'll see.
This was the only way I could see getting a nearly exact copy of an old guitar side. By taping the flexible measuring tape
around the guitar, my vertical dimensions could be transferred to the cardboard at exact increments. BTW, it sure seems
that Martin used the metric scale when laying out these old guitars, they line up perfectly in mm's, not so well in inches.
I'm sure there are lots better ways to do it, this one seemed to work well for me.
Thanks to all for your input and ideas, greatly appreciated.
Best
Bruce
Edit
Just a photo of the cardboard template, it does not look like much but is quite accurate. Just laid it up next to a side, should work well. I don't want anyone to think that I'm under the impression that I'm re-inventing the wheel here, I'm sure many of you have done the same thing, only better. This was just an attempt to see what I could come up with as I'm
trying to copy a specific guitar as closely as possible.
