MIMF

So an aquantence of mine has hired me to repair a very sad looking autoharp. It's soundboard has majorly separated cracks in several places, and it's warped in oposite directions beyond belief. Because I've never worked on an autoharp before and I want the interesting experience, I am not charging him nearly what I might if this was a guitar rebuild.

Anyway, because it's an old, dead, black oscar schmidt autoharp- and because of the low resale value on ebay, I am replacing it's soundboard.

The original sound board is 1/4" thick with maybe a single hefty brace perpendicular to the soundboard grain, and I have a 1/4" thick Port Orford Cedar replacement soundboard. However I don't want to blindly replace the soundboard and miss a possible opportunity to improve the instrument's volume and tone.

Can I sand the soundboard a little thinner and add more braces (ladder or maybe an x brace?), or should I just leave it braced and as thick as the original was?

I have discovered that x braced (cross braced) autoharps exist, but I can't find a picture of exactly how it's done.

Probably your most critical concern will be the frame including the pin block. If the frame is coming apart nothing else really matters until it can be made solid. The thickness of the soundboard I think is not critical, guitars have soundboards about 1/8" or less and they have the strings attached to the center of it. The autoharp has the strings attached to the frame, so the soundboard is under less stress, except for all the string tension.

Check out hammered dulcimer construction, as they are more similar to autoharps than just about any other instrument. They often use thin laminated (high quality plywood) for soundboards because it resonates reasonably and is MUCH more stable than solid wood like spruce.

The frame pieces are alright, although a few of the joints were failing/rotating at the glue line, and a handful of the tuning pins are rather loose. Nothing I can't fix. These joints will be unglued, and reglued with some carbon reinforcement inserts. Why go through all this trouble you may wonder? Because I want the experience.

Thanks for the dulcimer tips.

You might want to get a copy of The Autoharp Owner's Manual. It's well worth the read.
http://www.amazon.com/Autoharp-Owners-M ... 0786658835