Threading to a shoulder?
Threading to a shoulder?
I have a bunch of 1/4" check valves to make (for cold water) and made a first attempt today.
The two halves of the valve thread together with a 3/8-24 thread but even reversing my die to finish the male threads, I can't get as close to the shoulder as I would like.
Is there a way to get close to the shoulder (without grinding up a custom tool bit and threading on the lathe)?
BTW: It works fine.
The two halves of the valve thread together with a 3/8-24 thread but even reversing my die to finish the male threads, I can't get as close to the shoulder as I would like.
Is there a way to get close to the shoulder (without grinding up a custom tool bit and threading on the lathe)?
BTW: It works fine.
-
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Re: Threading to a shoulder?
What about dropping a parting tool in between the thread and the shoulder after threading? (or before, for that matter)
Re: Threading to a shoulder?
I have very little wall thickness at that point but will try that tomorrow. I DID use a countersink in the female thread. I need about 0.100" more engagement.James Powell wrote: ↑Sat Nov 03, 2018 5:31 pm What about dropping a parting tool in between the thread and the shoulder after threading? (or before, for that matter)
- ChuckHackett-844
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Re: Threading to a shoulder?
Can you make the male part longer to get more thread?
You might be able to grind the back side of the die to get closer (don't suppose you have a surface grinder?).
Since you said that you reversed the die I assume that this us not a pipe thread. You could turn off the hex from the male, thread the entire part, and then use a nut to lock the parts. You could even solder the nut on and again have a fixed nut/shoulder.
You might be able to grind the back side of the die to get closer (don't suppose you have a surface grinder?).
Since you said that you reversed the die I assume that this us not a pipe thread. You could turn off the hex from the male, thread the entire part, and then use a nut to lock the parts. You could even solder the nut on and again have a fixed nut/shoulder.
Regards,
Chuck Hackett, UP Northern 844, Mich-Cal Shay #2
Owner, MiniRail Solutions, LLC, RR Signal Systems (http://www.MiniRailSolutions.com)
"By the work, One knows the workman"
Chuck Hackett, UP Northern 844, Mich-Cal Shay #2
Owner, MiniRail Solutions, LLC, RR Signal Systems (http://www.MiniRailSolutions.com)
"By the work, One knows the workman"
Re: Threading to a shoulder?
Take the male end with the hex.....drill and tap it all the way thru...loctite in your threaded stud at the length you want it to protrude past the hex, the top side can be faced off, or turned to any other size you wish if you leave enough material sticking out.
Re: Threading to a shoulder?
Use an o-ring in the joint!
Or relieve the threads in the female hex piece.
~RN
Or relieve the threads in the female hex piece.
~RN
Re: Threading to a shoulder?
Saw your thread title. Is this in regards to fabricating a check valve...for an injector? ...axle pump? ...crosshead pump?
Reason for asking, had a problem several years ago where repeated pounding of the stainless steel check ball against the brass for the exit check valve seat, eventually pounded the opening closed. Then, no water flow and in fact was blowing feed water tubing off the hose barb (system gave way at the weakest point).
To resolve this problem, silver soldered a wafer of bronze (silicone?) on the brass threaded end cap for the pump. Drilled the hole thru. Beveled the hole opening. And then...used a Dremel grinding disk in a hex holder in the mill to cut (6) slots. Total contact area for the check ball was maximized while allowing sufficient opening for water passage when the ball was lifted.
Need pix? Just ask. Carl B.
Reason for asking, had a problem several years ago where repeated pounding of the stainless steel check ball against the brass for the exit check valve seat, eventually pounded the opening closed. Then, no water flow and in fact was blowing feed water tubing off the hose barb (system gave way at the weakest point).
To resolve this problem, silver soldered a wafer of bronze (silicone?) on the brass threaded end cap for the pump. Drilled the hole thru. Beveled the hole opening. And then...used a Dremel grinding disk in a hex holder in the mill to cut (6) slots. Total contact area for the check ball was maximized while allowing sufficient opening for water passage when the ball was lifted.
Need pix? Just ask. Carl B.
Life is like a sewer...what you get out of it depends on what you put into it!
I don't walk on water...I just learned where some of the stepping stones are!
I love mankind...it's some of the people I can't stand!
I don't walk on water...I just learned where some of the stepping stones are!
I love mankind...it's some of the people I can't stand!
Re: Threading to a shoulder?
The groove made by a parting tool only needs to be the same depth as the thread. If you have enough wall thickness for a thread, there is enough wall for a groove to remove only the thread at the shoulder.DianneB wrote: ↑Sat Nov 03, 2018 5:37 pmI have very little wall thickness at that point but will try that tomorrow. I DID use a countersink in the female thread. I need about 0.100" more engagement.James Powell wrote: ↑Sat Nov 03, 2018 5:31 pm What about dropping a parting tool in between the thread and the shoulder after threading? (or before, for that matter)
David
Re: Threading to a shoulder?
The check is for crosshead pumps.
Thanks for all the suggestions gang!
I think I will remake the top (male) by threading a piece of rod 3/8-24 and making the hex portion as a nut soldered in place. That will also allow me to set the optimum ball lift.
I'll let you know how it works out.
Thanks for all the suggestions gang!
I think I will remake the top (male) by threading a piece of rod 3/8-24 and making the hex portion as a nut soldered in place. That will also allow me to set the optimum ball lift.
I'll let you know how it works out.
- tornitore45
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Re: Threading to a shoulder?
Just relieve the female part with a major dia for a couple of threads to make room for the unfinished threads on the male part.
Mauro Gaetano
in Austin TX
in Austin TX
- Bill Shields
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Re: Threading to a shoulder?
Dianne;
you are making this whole process over-complicated.
I just use a threading die to start, then turn the die around, then relieve the threads at the shoulder with a very narrow tool.
in reality, considering the pressures, you only need 2-3 threads to hold the cap in place.
you are making this whole process over-complicated.
I just use a threading die to start, then turn the die around, then relieve the threads at the shoulder with a very narrow tool.
in reality, considering the pressures, you only need 2-3 threads to hold the cap in place.
Too many things going on to bother listing them.