I'm in the process of assembling my 21F motor. One of the brass cylinder primers screws into its cylinder OK. The other doesn't. The threads in that cylinder are a little rough and, unless refreshed, are likely to chew up the softer brass of the (original) primer. I can't identify the primer threads. It looks like 28TPI with an outside diameter of 13/32" but tapering by about 1/64" top to bottom. I fear that this will turn out to be an oddball thread with no readily available tap - but hope remains.
Can someone identify the thread size for me and then I can start hunting for a suitable tap.
(And yes; I know I should have sorted this out before the cylinders were bored and plated and I was well into motor assembly
)
Can someone identify the thread size for me and then I can start hunting for a suitable tap.
(And yes; I know I should have sorted this out before the cylinders were bored and plated and I was well into motor assembly
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