These are solid steel mandrels used to remove dents from valve casings and to straighten casings if they are sprung. Easier, faster and more safe to use than reamers and almost impossible to damage a casing using these mandrels. They are not adjustable, so you must know the size you need or the brand and model of the instrument. Precision
5.0
7 ratings
5
4
3
2
1
I received a mellophone from a local high school that all the valves were seized. I ordered the casing mandrels and got the mellophone back to playing condition in a happy Band Director.
R
Rich · August 11, 2026
Works exactly as it was designed to . Thank you so much.