What would you use to sand, reduce the thickness of a flat rubber washer?
Sandpaper? Most likely I only need to remove 1/64th" at most 1/32". I have
plenty of washer so trial and error will get the right thickness sooner
rather than later.

Experience with this group dictates that I must explain the why.

We have a transfer valve on the garden tub. The shower head broke. The part
is obsolete, replacements from Delta are made differently and because of the
deck mount would not be a good choice. Changing out the deck mount would be
a major project. I bought a hand held shower unit at Lowes, but the thread
run length is slightly different and the old washer was bad. The OEM washer
is also obsolete and did not even have a part number. I substituted a
regular flat washer but it is slightly too thick resulting in the angle of
the dangle being wrong.


--
Colbyt
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