Threading short pipe nipples with Reed block dies.

[aametalmaster]

 I have had a 44 year old Craftsman AKA Reed Mfg hand pipe threading set for about 18 years. Bought if from a guy going out of his plumbing business. The ratchet handle houses a 4"x4" square threading die and an alignment collar to keep the threads straight. It works great doing my gas line and boiler lines around my house. I moved lots of pipe over the years. But it is hard making nipples under 4" because the length is too short to hold it in the vise and with the alignment collar there isn't enough room to start the threads. I have fudged this and that and have had good results but its time consuming. So I dreamed up this piece of pipe that was threaded and a 3,000 lb coupling was screwed on. The 3,000 lb couplings are the thick steel ones not the cheap cast ones from the hardware store. Then I chucked up the small pipe with coupling and turned the coupling down to fit the next size pipe. Hence a 1/2" thread will now use a 3/4" alignment collar when making the short nipples. The one end for the short nipple is threaded like normal, cut off the desired length and turned into the 3,000 lb coupling and pipe that is now in the pipe vise. Then the ratchet is started threading until its done (lots of good sulfur threading oil here). Then the die is removed and the now short nipple is turned out of the coupling. Ready for the next one. Sounds like a long process but it isn't and the results are good. Made 2 more adaptors one for 3/4" and another for 1"...Bob

[Chillylulu]

In the field we often hsd to cut short nipples (down to a 1" x  "close" nipple at 1-1/2" long.  That's pretty short considering that each thread is 1" long.

Our threaded pipe is 1" to 2" . 2-1/2" and larger are usually shop cut, if needed at all. We don't use smaller pipe much in fire protection, except for trim on some valves. Bigger pipe is usually grooved.  In fact, I usually would groove 2" pipe also. 2" just tends to have more leaks when threaded.

We used the same method that you show, with a couple of refinements. We carried a set if these nipple chucks in our trucks,  they were preferred over the Rigid nipple chuck mostly.

The best coupling we found were the ones used by electricians. The threads go straight through and aren't tapered like pipe threads.  They last forever.

The best secret is to cut the threads on the nipple chuck pipe long, so that they go through the coupling and only leave 4-5 threads showing on the receiving side. Since hand tight is 3-1/2 threads, that leaves just1/2 to 1-1/2 threads to bottom the coupling out. This makes the nipple easy to remove without having to wrench too much. It still can get pretty tight, jammed against the other pipe in the chuck.

We used pipe because that is what we had available.  If I was going to make a great chuck I would use solid stock for at least the end of the pipe. I think it would make a better face to run the nipple up against. Welding a plug inside the end would work well.

The most threads I cut in one day was just over 1500. It was on a Swift-Mercury threader with a Landis head. Automatic chucking with a foot pedal. That was in the shop though. I spent quite a few days cutting droos. That job sucked and was extra dirty too boot. 

The drops I was referring to are the droos down to sprinkler heads. We used to cut them long when installing the pipe.  When the ceiling was in we would go through and cut tge droos to fit. When there were several men on the jobm and just one power machine, one person woukd have to be the "cutter." Usually the lowest rank  apprentice got the job. Cut threads as fast as you could as the other guys brought marked drops to you. If you were close you would run and get the drops where they were laying on the floor and run them back after cutting them to length.

Chilly

[aametalmaster]

Thanks Chilly. Orig I was going to make the adaptors from bar stock that way they would have the shoulder you talked about. Great idea using the straight thread coupling as we have zillions of them at work. But for all I do this should work fine...Bob

[Aunt Phil]

Strictly from repressed memory, 3/4 pipe is the same OD as 1" bar stock and ½" pipe is the same as 7/8 bar stock or pretty damn close thereto.

Grab a coupling, run a tap in the coupling to oversize the tapered female a hair or 2, then back the tap out.  SS couplings work best at stress resisting over the life of the chuck.
Stick a nipple into the side you've overtapped hand tight.  Then bring a threaded solid up to face it, from the other side of the coupling.  If possible employ hex rod turned down to fit inside the coupling for best chucking in a machine. 
With the nipple & solid mated inside the coupling, put 3 or 4 tacks onto the coupling on the end where the solid is,  cool slowly while watching the assembly with a mug of coffee and beater to employ against anyone stealing the tool you just made. 

After each use, LOCK the nipple chuck in your tool box.  The damn things evaporate fast.

I figure I've made at least 537 of these chucks in different sizes, and I still don't have a one in my tool boxes.

[aametalmaster]

After each use, LOCK the nipple chuck in your tool box.  The damn things evaporate fast.

I figure I've made at least 537 of these chucks in different sizes, and I still don't have a one in my tool boxes.

Thanks. I understand that...Bob

[Chillylulu]

Pipe O.D.'s:
1/2"       .84    13/16
3/4"     1.05   1-1/16
1"         1.315 1-5/16
1-1/4" 1.66   1-11/16
1-1/2" 1.9     1-7/8
2"         2.375  2-3/8

I rounded them to the nearest 1/16".
I think that 1/16" up dn would be close enough.

Chilly

[Aunt Phil]

Pipe O.D.'s:
1/2"       .84    13/16
3/4"     1.05   1-1/16
1"         1.315 1-5/16
1-1/4" 1.66   1-11/16
1-1/2" 1.9     1-7/8
2"         2.375  2-3/8

I rounded them to the nearest 1/16".
I think that 1/16" up dn would be close enough.

Chilly

You cheated and copied off a chart.

[turnnut]

 and you could hear a pin drop !

[Chillylulu]

Pipe O.D.'s:
1/2"       .84    13/16
3/4"     1.05   1-1/16
1"         1.315 1-5/16
1-1/4" 1.66   1-11/16
1-1/2" 1.9     1-7/8
2"         2.375  2-3/8

I rounded them to the nearest 1/16".
I think that 1/16" up dn would be close enough.

Chilly

You cheated and copied off a chart.

Not exactly, I copied off a couple different sites some time back and have them in an excel reference file that I have. It akso has various hose threads, groove dimensions (copied from Victaulic reference books) and all pipe dimensions up to 22" or 24".

I was drawing pipe and fittings in 3-D in Autocad. Making details for some documentation on a program I have been working on for the last 18 months.

When I draw something like that I am usually very accurate. I'll get some screen shots tonight of the details. I even drew two different 2-1/2" threads on a hose valve. Pipe threads on the inlet and NST hose threads on the outlet.

Chilly

[aametalmaster]

I even drew two different 2-1/2" threads on a hose valve. Pipe threads on the inlet and NST hose threads on the outlet.

Chilly

30 years ago I was a union sheet metal worker and the shop I was at had a small machine shop that was left behind by a pump company that moved across town. Well we did work for them making column pipes and brackets since we had their tooling and machines. One of the pipes I made was 2" and threaded normal 2" NPT, for the start. Then chucked in a lathe and the thread picked up and cut for another foot or so. It was for a ring that screwed on the straight threads to hold the pipe upright thru a floor. And the taper threads sealed the fitting...Bob