Machining a Globe Valve - PM Research kit

[Dan Willey]

Hi Bill,

Thanks for the posts and videos. (I have several of the PM casting trees that I will machine one of these days.)

Question... What are you going to do to keep the "knobs/handles" from turning on the stems? (Not sure what the PM drawings show but you may want to broach a square (drive) hole in the "knob/handle" rather than a simple round hole... and file a square male drive on the stem.)

Thanks,
Dan

[Bill C]

Hi Dan,

Thanks for the feedback, kinda feel like I'm talking to myself sometimes... The prints call for a straight knurl on the spindle, push on the handle, followed by a threaded portion for the handle nut. I've ordered straight knurl wheels from Little Machine Shop and will use them in my homemade scissor knurler.

The L M S website recommends using only one knurl cutter along with a smooth "blank" wheel. Guess I will take their advice on a test piece and see how it works.

By the way, I also had to order some 6-40 taps and dies for the spindle and the bonnet. The 1/4" and 5/16" globe valves both use that size.

I took a break yesterday and just sketched out some parts today. May grind some form tools tonight as the bonnet calls for a 5/32" radius concave section. Will keep updating as I have something useful to show.

Please feel free to comment and ask questions, I'm hoping to make this a "go-to" thread for future, first-time valve-makers.

Thanks,

Bill C.

[Bill C]

I made my first bonnet tonight, took a short video afterwards. Here is a link to it.

http://youtu.be/JNB3Pfega1s



I took a few still shots that I will upload soon. The main help, I suppose, is showing the form tool and talking about the order of operations that made it pretty easy to turn. Lathe work is fun. Have a great weekend!

Bill C.

[Harold_V]

Nicely done, Bill.. especially the video.

Harold

[Bill C]

Harold, thanks so much, I appreciate your comments!

All - here are some still photos I took last night showing various stages of turning the first bonnet. Most notable are the use of the tangential tool holder and the form tool.

Bill C.

[Bill C]

I made three more bonnets on Saturday. They went faster than the first one since I made more use of the form tool (see photos above) and also used more of a production mode. By that I mean I turned, formed, drilled and tapped all of them from the base side, then cut them off and did the next one. When I had all three done to that point, I inserted the 5/15" round 5C collet and the 3/16" - 40 die in the tailstock die holder and threaded the top portion of all three in succession.

Next up will be the spindles. More fun on the lathe!

Bill C.

[Bill C]

Hi Everyone,

Happy Father's Day to all the dads out there! I posted a short two and a half minute video showing my progress to date. Made the nuts no problem, but having challenges with the spindle. Broke one while threading, so I consulted Fred V for advice. He gave me two excellent suggestions that I cover in the video. Simply put, they are to turn a short section of the spindle at a time and to use an 8-40 die first then follow with the 6-40 for final cut. Thanks, Fred!

Here's the link to part 8;

http://youtu.be/okzPxe_xyZo



Cheers,

Bill C.

[Bill C]

Quick update, got the new dies and tried them tonight. Worked beautifully, thanks again, Fred!

Here's a minute and a half video show 2 completed spindles.

http://youtu.be/SXQGcJWJQz8




Bill C.

[Bill C]

Happy Independence Day weekend,

I just posted a short video showing the square filed on the spindle end (in lieu of the straight knurls) and the handle with the square filed hole. I've made several and they are pretty simple. Here's the link to the video (part 10 in the series):

http://youtu.be/ybt2UFe2qzc



Plans now are to make a few more valves and then test them with some water under pressure. Not sure how I'm going to do that just yet. Will let you know....

Stay safe out there...

Bill C.

[Fred_V]

Test them with air and stick them in a jar of water. Just make a fitting to fit the valve with a 1/8 pipe thread on the other end and connect to your compressor.

[Oilcan]

Bill:

Thank you for taking the time to film, photograph, and explain your adventure with machining the PM Research globe valves. I do believe you've alleviated some of the anxiety of taking on the project.

Good job!

Neil

[Bill C]

Fred - thanks, great idea!

Neil - thank you for the nice comments. This has been a fun project and valuable learning experience. It is fun to learn by applying the techniques others have taught me and it is rewarding to pass them along in this forum.

Best Regards,

Bill C.