Reed organs contain hundreds of screws. Many of these screws are removed and reinserted many, many times over the instrument's lifetime; what does one do when the screw hole becomes worn out and the screw can no longer be tightened? Most of us have instinctively reached for a matchstick, shoe-peg, or toothpick; but this is a very temporary fix. The permanent solution is to add new wood and drill a new pilot hole. I use a 5/8" plug-cutter in my drill press to make a face-grain plug of hard wood (curly/birdseye maple is great; it's very hard, and the interlocked grain makes it more split-resistant) and glue the plug into a hole bored with a 5/8" Forstner bit. If the component in question is cabinetwork, one must bore out material from the back or least-noticeable side. In this case, the plugs will be covered by the assembly that screws down into the holes, You must use face-grain plugs, not dowels, even if it seems easier, screwing into end grain is not a long-lived cure the screw threads c create short-grain wood threads, which shear off in a few cycles of taking apart.
Another situation is typical on the top of the windchest or soundboard, where on organs of extreme age, the area around the screw head locations is literally worn away so the screws have become countersunk when they had been flush when the instrument was new. The dry wood of the soundboard has become weak, split, and friable, making a mechanical and aesthetic defect. The same repair technique is applicable, but to better match the wood-tone of old wood, I generally use cherry for these plugs. Boring out the old material should be done with a steady hand to create a smooth-edged hole with the very minimum of tearout. A very sharp Forstner bit is called for. The plugs should be planed or chiseled to almost-flush, and then a cabinet scraper and sandpaper will finish the task. Re-drill the hole up from below with a hybrid brad-pint bit that resists tearout from either sides. The bits made by Festool I have found are very well-suited.
Casey Pratt, restorer of neglected harmoniums!
I run a one-man reed organ restoration workshop; here are my ongoing restoration exploits, as they happen.