deskthority

Look for a good brand, I have no clue what you can find in your hardware stores Here for example Stanley is pretty decent

I used a very old jewelry file. It wasn't broad enough to fit the hole, so it made it harder to achieve a good result. But I also underestimated how much trouble a bad job would give me and rushed it. Should have been more patient!

Broadmonkey wrote: I wouldn't recomend you use a Dremel. With that you can't maintain a square hole and it's harder to make it precise. I would just bite it and use a file.

When making handmade flutes, I use a combination technique on the headjoint, which is by far the most critical hole. For one thing, it's not round, it's more of a rectangle with rounded corners. For another, it's not cut straight, but at about a seven degree angle. I drill it straight, enlarge it with the stone grinder bits on a rotary tool, and hand-finish with flat and round files. For tone holes, I just drill them undersized and use the stone grinder bit to tune them individually. Unfortunately, the inner diameter of PVC plumbing pipe is inconsistent, so I have to compensate for the variations via the size of holes, which means no two come out with exactly the same holes.

Of course, musical instruments are not often made of aluminum or stainless steel, but mouthpieces sometimes are, such as Berg Larsen. They are notoriously difficult to work on, and sometimes they need it because there are certain dimensions that must be spot on or they just won't work at all.

Muirium wrote: Anyone got good metal file recommendations? The ones I've got are old and blunt, so I was getting nowhere when I tried. Trouble is: files all look alike in the shops…

Be aware that rust is not an indicator of poor quality. Not being stainless is one of the prices to pay for the kind of good, hard tool steel you want in a file. Brittleness is the other thing you're going to have problems with. Do not use files as levers. They will snap.