Search found 31 matches

by Michael Bretti
Thu Jan 18, 2018 10:12 pm
Forum: Vacuum Technology (& FAQs)
Topic: Double-Checking Diffusion Pump before Buying
Replies: 6
Views: 171

Re: Double-Checking Diffusion Pump before Buying

Josh, No problem, glad to provide some help and assistance! You will find this forum has such an incredible wealth of knowledge that can provide you with an extraordinary amount of information from all of the cumulative expertise of other members here. If you have done as much research as you can an...
by Michael Bretti
Wed Jan 17, 2018 1:52 am
Forum: Vacuum Technology (& FAQs)
Topic: Double-Checking Diffusion Pump before Buying
Replies: 6
Views: 171

Re: Double-Checking Diffusion Pump before Buying

If you are looking to make your own adapter plate, here are some great cheap resources of aluminum plate:

General 6061 Aluminum Plate Stock:
http://stores.ebay.com/Stoners-Tools-and-Raw-Materials

Custom Cut Aluminum Plate Stock Including ATP-5:
https://www.midweststeelsupply.com/store/
by Michael Bretti
Wed Jan 17, 2018 12:36 am
Forum: Vacuum Technology (& FAQs)
Topic: Double-Checking Diffusion Pump before Buying
Replies: 6
Views: 171

Re: Double-Checking Diffusion Pump before Buying

Water cooled is standard for diffusion pumps, and shouldn't take too much to cool them, especially one of that size that is not too large. For comparison, my 850W EO6 diffusion pump with an inlet diameter of 5" requires 75 L/h or .27 gallons/min cooling water flow at 20C, which is very easy to find ...
by Michael Bretti
Sun Jan 14, 2018 7:50 pm
Forum: Images du Jour
Topic: Arc polarity for fusing wire?
Replies: 6
Views: 264

Re: Arc polarity for fusing wire?

I was able to do this very effectively (albeit unintentionally at first) with a tube-based RF oscillator I built a while ago. Several hundred watts of power in. I think maybe 700V in as well. Not sure about the output current, but definitely in the upper mA range at maximum power. About a few MHz fo...
by Michael Bretti
Sun Jan 14, 2018 3:15 pm
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

Thank you very much. I will send you an email to your gmail that was displayed on the baffle pictures in your link above. Looking forward to it!
by Michael Bretti
Sat Jan 13, 2018 5:17 pm
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

Jerry Biehler, Thank you so much for your help on this, I truly appreciate it. I have just been CADing up some quick models based on your pictures and dimensions to see how I could fit the baffle to my current system with a simple ring adapter, but I think it could work. The overall dimensions shoul...
by Michael Bretti
Fri Jan 12, 2018 4:10 am
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

Jerry Biehler, Thank you a ton for your response and help looking into this, I greatly appreciate your efforts, as well as everyone's help in their responses so far. I made up a quick drawing sheet of the top flange of the diffusion pump from my model: Edwards EO4 Diffusion Pump Drawing - TOP.pdf To...
by Michael Bretti
Fri Jan 12, 2018 2:34 am
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

So I went back to my diffusion pump just to check out where the stack ends at the top to try and gauge how I could implement my baffle idea. It turns out the stack is secured at the top with a cap that has two adjustment screws to clamp it to the wall: 20180111_211314.jpg 20180111_211333.jpg Looking...
by Michael Bretti
Thu Jan 11, 2018 8:02 pm
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

Jerry Biehler, Thank you for your input on your experience with diffusion pumps. Reading more into it, while the oils themselves may be rated for much lower torr, I failed to account for the fact the diffusion pumps can experience considerable back-streaming during pump-down, especially when the for...
by Michael Bretti
Wed Jan 10, 2018 7:05 pm
Forum: Vacuum Technology (& FAQs)
Topic: Question About Design Trade-offs for Backing Pumps
Replies: 20
Views: 477

Re: Question About Design Trade-offs for Backing Pumps

A bit of a correction to the above statement. While I generally will not be running with the ion pump except for keeping the system under vacuum when everything else is off and already pumped down, I would like to try and run it if I am doing tests with either electron guns or miniature thrusters. T...