Quick update on construction

[apollo]

Hello everybody
Yes, I'm still alive. I've been away for a long time working on several projects (fusor and Tesla coil, mostly). Thanks to the help of a professor at Union college in Schenectady, my Robinair issue will soon be solved. By simply sticking a hose over my 1/2" NPT fitting, he was able to get the pressure down low enough that a poissor was formed. Hurray!

Still, any help finding what thread is on the Robinair pump would be greatly appreciated (that is, AFTER the tee with the 1/2" Acme and 1/4" MFL fitting is removed!). If not, we'll have to make a part (or get a better pump).

[apollo]

Today I installed an accurate gauge and I'm right at 1000 microns. I should be able to get back down to well under 100 if I can ever figure out what this fitting is.

[Edward Miller]

There's a very good article on Swagelok's site that goes over 10 different types of pipe connections.

http://www.swagelok.com/downloads/webca ... itting.pdf

[apollo]

Thanks edmo. I was wondering if you had any idea what the bottom fitting could be:
http://www.usatoolwarehouse.com/Merchan ... -15495.gif
After reading over all of them, it doesn't seem to fit any really well since it's not flared at the bottom. Any ideas?

[Edward Miller]

It looks like the SAE Straight-thread fitting shown in the picture. The seal is provided by the rubber material, not by the threads. I would say that your best bet is to look on eBay for Swagelok parts there are many standard sizes, either Compression, NPT, or VCR fittings will work. I prefer 1/4 Compression fittings, there's a good seal, I can cut the exact length of pipe I need, and I can reuse the ends without a new washer (like in VCR) (1/8" compression also works). NPT is okay for some of the other interconnections (like to the regulator, vacuum, etc)...