Here you can find out everything you need to know:
Fingerboards are usually made of ebony, a very hard wood.
Nevertheless, wear and tear occurs over time due to playing and the constant pressure of the string on the fingerboard:
Grooves develop
grooves
scratches
scratches, indentations, unevenness
This impairs playability in the long term. Rattling or buzzing noises may occur or intonation may deteriorate.
This is why it is important to have the fingerboard scraped regularly. If you play a lot, this is necessary once a year, if you play 0.5 hours a day, approximately every 2-3 years.
If you hold the violin towards a window and look over the fingerboard from the scroll, you may already be able to see small ripples that look like a washboard. Then it is time to have the fingerboard removed.
What does “peeling off the fretboard” actually mean? What exactly is done?
The fingerboard is finely planed, usually using a one-handed plane with a metal sole. The result is a fine, smooth and minimally concave shape along the length of the fingerboard. The lowest point is approximately the thickness of the respective string. This means that the fingerboard on the E-string side is flatter than on the G-string side. This allows the strings to vibrate freely.
After planing, the surface is sanded with different grits of sandpaper and finally polished so that it is completely smooth again.
When removing the fingerboard, defects in playability can also be rectified if the fingerboard still has sufficient material. For example, the rounding of the cross-section can be changed if necessary.