[Right side thumb strap on English concertina detatched.]

Bob Snope replied that these screws are not threaded into wood but into small leather washers inside the wooden end. Following his instructions I removed the end, found the three washers (loose in there) and put them back on the screws. Then put the end back on and it solved the issue!  I think the problem came from my having had the straps too tight, and also lifting and handling the instrument in a way that put excessive strain on the strap.  

[Right side thumb strap on English concertina detatched.]

2 hours ago, Steve Schulteis said:

 

I'd emphasize to fill with a wooden plug, and not a dowel. The difference is the grain direction. If you use a dowel, you'll be drilling into end grain, and the bit will want to wander. Plug cutters are available at the big home centers, at least in my area.

Thanks, I will keep that in mind.

[Right side thumb strap on English concertina detatched.]

3 hours ago, Theo said:

Seconded,  fill the holes with wood, not with any glue mixture.  Also investigate why the screw pull or out.  Is it too short or too thin?

I'm going to look into that.

[Right side thumb strap on English concertina detatched.]

8 hours ago, JimR said:

The big question is why did it pull loose? Was it already damaged, or did you rip it out?

I didn't abuse the instrument, but I had adjusted the thumb straps rather tightly. 

[Right side thumb strap on English concertina detatched.]

Yes the threads in the screws look good but the wood inside is apparently damaged. Filling the holes and re-screwing sounds like the best approach. Thanks, all.

[Right side thumb strap on English concertina detatched.]

The screws came loose. Threads stripped. Maker no longer in business. Friend suggested Super Glue Gel but I have not taken any action yet. Does anyone have suggestions? (Fortunately I have another instrument to play in the meantime!) Appreciate your consideration.

John C.

Photo attached.