Bought a aluminum frame with rear suspension, got it sanded and powder paint. While they matched the color perfectly, it's smooth and evenly distributed BUT UNFORTUNATELY totally forgot to cover any threads.
Managed to remove the paint from bottom bracket threads, seat post tube and frame head tube with a copper brush, sandpaper and gently using an awl.
Problem is the #5, #6 threads for equipment and derailleur which is a part of a frame.
Could use a tap on #5 and #6, but the threads aren't damaged so there's no need as they are undamaged.
Any way to remove the paint chemically? Tried a hydrocarbon solvent that I left for 4 hours without slightest effect.