pipe fittings

[Mac]

Hi all,

I'm looking for pipe fittings and nipples (black or galvanized) that have National Pipe Straight threading. 1 1/2" - 3" would be great.

I'm building equatorial mounts for telescopes and I need the threads to engage much further than the tapered threads will allow. The joints from nipple to fitting ("T" and 45 degree elbow) act as bearings allowing the telescope to turn at declination and right ascension. Am I correct in assuming the nipple will turn all the way through the threads in the fitting?

Also, in the two different systems are the male and female threads both tapered (NPT) or straight (NPS)?

Does anyone know of an internet retailer or supplier I could contact by phone?

Any info would be appreciated. Thanks for your time.

-Mac

Email or post, either is fine. Please remove "nospam" from address to email.

[Mark Monson]

A hardware store may be able make the nipples on a pipe threading machine. Straight pipe thread can be formed by simply threading through the die instead of stopping at the usual place for tapered thread. Some threading machines automatically release the die at the proper depth. Better for your purpose is the less fancy method favored by many plumbers that features a hand threading die (Ridgid 12R) with a power rotated vise ( Ridgid 300).

The fittings may be more difficult to come by. Straight cut ( threaded through with no taper) couplings are common enough, but not tees and 45's with straight thread. Perhaps by welding couplings together you could make the fittings you require.

MM

[Ned Flanders]

What about threaded rod??

[Mac]

I found the parts I was looking for. Thanks for the input.

-Mac

[Mark Monson]

Tell us where you got em so we can help the next telescope builder that comes along.

[Mac]

offers nps fittings and nipples in iron and aluminum. They deal in traffic signs and lights, etc.

[HandymanNW]

Electricians cut straight threads on rigid galvanized steel electrical conduit which is the same size as standard galvanized steel pipe.

[Mac]

Thanks Handyman, didn't know that. What fittings and size of conduit are available? Conduit is quite a bit thinner than pipe but I may be able to thread the galvanized tapered thread right through the straight threads of the conduit fitting. Ya think? Thanks again,