On 6/16/22 11:18, Nick Andrews wrote:
Hello Dave, funny you mention this...? I finally got my cart (old Beckman ultracentrifuge over to TX from NM.? Yeah, it's still on the trailer, but I have to clean it off to haul back there at the mighty 4th to try and finish my move to San Antonio and sell the house (it's only been since Aug 2017 that I started moving).
Ugh, moving sucks!
Super heavy duty cart. Even after I removed the reefer unit and drive motor assembly (bearing had failed and leaked oil all over), roughing pump, diff pump, control panel/top, top sliding door plate assembly, electronics, the thing still weighs over 400#.? I think I am going to try to block off the hole in the bottom of the chamber and reassemble it to use as a vacuum chamber. The outer ring has a Hastings type TC gauge in it already.? Probably don't need the 1.5" thick explosion shield ring that sits inside that but until I need it for something else I think it will be just fine where it sits now.? I plan to reinstall the Welch Duo-Seal (1 of 3 I have) as the roughing pump or use the Edwards RV one I have, and then use a small turbo setup I picked up off ebay (if it works).? Have a couple of MKS Loadlock pressure sensors for the system, and a few KF25 valves.
Very interesting; I don't know much about centrifuges. They're mostly used for medical stuff, which I don't get into. So these big ones have vacuum systems in them?? I wasn't aware of that.
I bought (I think) a nice TC gauge with a bunch of tubes at auction from Bentley's in Albuquerque along with a ~30L dewar, about fifty 5C collets and around 50 slitting saws.? A friend picked them up for me and I plan to drive up there from Las Cruces week of the 4th to pick it all up.
Nice! Take pics!
Diff pump was assembled to the housing with a flange and o-ring with thumb screws which I will need to adapt to the ISO63 (?) flange on the turbo.? Was looking at a cross that is ISO/KF63 straight through and a couple of KF25 on the side.? But there is no window in the top plate, which I'd like to have but might interfere with being able to use the slide mechanism to open and close it (assuming I am able to reassemble what I took apart before).
Have you seen the pricing on diffusion pump oil lately? Ugh. :-(
I mostly want a system to pump down tubes for lasers, neon and maybe in some crazy time try my hand at vac tubes or nixies.? And eventually maybe a fusor.? Still need to test the newer mill, Bridgeport 2J2 but I now have a horizontal attachment for it.
Sounds somewhat similar to what I want to do.
What I've been advised is to go with KF type fittings using centering rings and o-rings instead of conflat, as they are reusable versus the conflat copper washers.
The single-use washers do seem like a pain, but they're not THAT expensive if you aren't changing things around a lot.
-Dave
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Dave McGuire, AK4HZ
New Kensington, PA
Dave McGuire