In article ,
Jack Erbes wrote:

Chuck Tribolet wrote:

Sounds like an 8' 6dB VHF antenna to me.

We're talking about a BIG bolt that goes through the pedestal and into the
bottom of the
antenna? Standard size is 1" diameter, 14 threads per inch.

That thread is the 3/4" NPTS, the nominal O.D. is just under 1" so it
has become called 1"-14 TPI in the marine industry. NPTS means National
Pipe Thread Straight, it is the same as common 3/4" pipe and fittings
but not tapered.

Standard 1" bolts are either 8 TPI (NC) or 12 TPI (NF) and a strong and
yard mechanic can get 1" NF bolts to work on the antenna stubs. For a
few threads anyway. :)

Jack


When making custom mounts for the Marine 1"X14 Mount Threads, I use
my pipe threader with an adjustable die set, and cut the threads
just slightly deeper than the normal 3/4 NPTS setting. Been doing
that for years, and it works very well. Morad builds a Standard
1"X14 to 3/4 Pipe Slip-over Adapter, with Setscrew locking, that works
well, also.

Bruce in alaska
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