Good information, (below), thanks. On the issue of availability,
though, I have to wonder why they would NOT be available for sale?
Obviously, certain manufacturers of the multitude of ham-stick type
antennas use them. There must be a large scale source, somewhere!

Ed




As a modification to this, since you can stand 1/2 inch thread, how
about using a 1/2 inch bolt and brazing or silver soldering some 1/2
inch ID tube over it? Not only will this be easier than trying to
center the 3/8 and potentially stronger than epoxy, but it would keep
that RF continuity.

This is the sort of part that's expensive to turn out as a one-off
part, but very easy to manufacture on an NC lathe -- even a cam-driven
automatic screw machine would handle this with ease. Because of this
I suspect that there aren't any on the open market; rather a
manufacturer would just send drawings to their favorite screw machine
place to have them made 10000 at a time.

It's also the sort of part that's fun to make in limited quantity --
it looks pretty, you get to practice your threading, yet its not too
critical. So you might want to take up Paul's offer, perhaps with a
nice drawing. Just don't ask him to make too many.

Ed wrote:
(top posting fixed)


As a modification to this, since you can stand 1/2 inch thread, how
about using a 1/2 inch bolt and brazing or silver soldering some 1/2
inch ID tube over it? Not only will this be easier than trying to
center the 3/8 and potentially stronger than epoxy, but it would keep
that RF continuity.

This is the sort of part that's expensive to turn out as a one-off
part, but very easy to manufacture on an NC lathe -- even a cam-driven
automatic screw machine would handle this with ease. Because of this
I suspect that there aren't any on the open market; rather a
manufacturer would just send drawings to their favorite screw machine
place to have them made 10000 at a time.

It's also the sort of part that's fun to make in limited quantity --
it looks pretty, you get to practice your threading, yet its not too
critical. So you might want to take up Paul's offer, perhaps with a
nice drawing. Just don't ask him to make too many.



Good information, (below), thanks. On the issue of availability,
though, I have to wonder why they would NOT be available for sale?
Obviously, certain manufacturers of the multitude of ham-stick type
antennas use them. There must be a large scale source, somewhere!

Ed

Actually my point was that this is exactly the sort of market where
there _won't_ be a large-scale source, at least not an open one. It's a
market dominated by a few vertically integrated manufacturers, who have
no vested interest in commonality of parts and _do_ get advantages from
having design control over the parts they get. If nothing else it make
it much more expensive for the guy down the road to start up his own
operation.

Consider that nuts and bolts were not truly standardized until around
100 years ago. Before (AFAIK) then manufacturers would specify by size,
but there were no commonly used standards until the SAE got together and
made it happen. As a result nuts and bolts became commodity items and
the price went down.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Actually my point was that this is exactly the sort of market where
there _won't_ be a large-scale source, at least not an open one. It's
a
market dominated by a few vertically integrated manufacturers, who have
no vested interest in commonality of parts and _do_ get advantages from
having design control over the parts they get. If nothing else it make
it much more expensive for the guy down the road to start up his own
operation.

Consider that nuts and bolts were not truly standardized until around
100 years ago. Before (AFAIK) then manufacturers would specify by
size,
but there were no commonly used standards until the SAE got together
and
made it happen. As a result nuts and bolts became commodity items and
the price went down.



Understand what you are saying, but this item I am describing is
pretty much standardized, near as I can tell. Soooo many mobile antenna
manufacturers, including CB, use it on their 1/2" fiberglass rod based
antennas, that I am pretty sure there must be a sizable source,
somewhere.


Ed