Just about everything you do to a harp affects the tuning so it stands to reason the last thing you should do is adjust the tuning.
But how do you make adjustments to the tuning without messing up the shape of the reeds or undoing other hard-earned adjustments?
To lower the pitch using a file, you can support a blow reed while the reed plate is still on the comb using the Hockey Stick.
Place your finger over top and you are supporting the reed! As long as you file an area that you are supporting, you won't change the shape of the reed.
We usually support a reed to lower the pitch using a plinker/support tool. It's just a matter offiling the base of the reed from the inside of thechannel with a Swiss file.