CONN 20J piston OD?

[CachanillaPete]

I recently acquired a CONN 20J which I am restoring. This is my first time venturing into the instrument repair world. As such, I am acquiring some basic tools.

The CONN 20J needs some work on the valves and the casings. As such, I plan on purchasing the N58D Ground Casing Mandrel and the N28D Ground Valve Sleeve from Ferree's.

However, I don't trust the measurements on my valves given that they need reworking. My valves OD currently measure 1.223 inches.

Can someone confirm the same?

Thanks!

[KingBassTrombone]

My 20J's pistons measure as such:

1st- 1.218"
2nd- 1.219"
3rd- 1.219"

[roweenie]

Ferrees should know which mandrel to sell you - that's a very popular model (I haven't seen a recent catalogue, but IIRC, they used to list the mandrel by which instrument they were made for). They are very good about answering questions, just send an email or call.

Are the casings sprung?

[CachanillaPete]

Thanks all.

I honestly did not think about giving them a call. I am not familiar with the phrase "sprung". My 1 piston/casing appear to function properly. However, my 2 and 3 pistons/casings do not. The 1 piston does not function (cannot be inserted) in the 2 or 3 casings. Also, the 2 and 3 pistons do not function in the 1 piston.

That leads me to believe that both of the 2 and 3 pistons and casings need to be reshaped.