Help with Speedivac F203 Diffusion Pump / General Science and Electronics / Forums

Forums

4hv.org :: Forums :: General Science and Electronics

« Previous topic | Next topic »

Help with Speedivac F203 Diffusion Pump

1 2 3 4 next last

Move Thread

LAN_403

IntraWinding

Wed Nov 24 2010, 12:30AM

Registered Member #2261 Joined: Mon Aug 03 2009, 01:19AM
Location: London, UK
Posts: 581

I got a Edwards Speedivac Oil Diffusion Pump type F203 off eBay and I've got the following information from the badge:

Oil Charge 50cc
Heater Voltage 240V
Heater Wattage 330
Model F203
Patents 700978, 721667

Google doesn't add much, but can anyone get me a copy of this paper?

An assessment of some working fluids for diffusion pumps
D. Latham B.Sc., B.D. Power M.A. and N.T.M. Dennis B.Sc
Vacuum, Volume 2, Issue 1, January 1952, Pages 33-49

Any other information would be great if anyone has it?

I've stripped it down to clean it. There were a couple of bits bits of asbestos cloth stuck to the inside of the outer aluminium shell. I'm wondering if the whole gap between the outer shell and the heated part of the pump was insulated with a layer of asbestos previously. Has anyone seen that done?

Proud Mary

Wed Nov 24 2010, 01:25AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Hi Alan,

if you mean what sort of oil ought you to put in it, I'd suggest DC702, or Tetrasil 747.

Plazmatron knows a zillion times more than me about diff pumps, so you should see what he has to say about it.

Stella

IntraWinding

Thu Nov 25 2010, 02:16AM

Registered Member #2261 Joined: Mon Aug 03 2009, 01:19AM
Location: London, UK
Posts: 581

Thanks Stella. I'm wondering about:
that asbestos,
whether I can/should clean of the brown 'varnish' on the insides, and how
if the areas where copper shows through the silvery metal plating of the 'chimney' are a hazard to the oil (might catalyse it's cracking),
and what oils that scientific paper covers as they happen to use the same pump I have.

Any sign of Plazmatron, or should I PM him?

Ash Small

Thu Nov 25 2010, 02:32AM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

I've two of these pumps, one unused and still in the box. I'll be using them for various plasma projects and mayby vacuum induction casting.

As I understand it, the oil you require depends on the ultimate vacuum you intend to achieve.

What projects do you have in mind? What ultimate vacuum do you need to achieve?

I understand the best oil to use is Santovac, but you may find a cheaper oil is suitable, depending on your intended use.

If you can post more details of your intended project, I may be able to dig out more info.

Proud Mary

Thu Nov 25 2010, 09:18AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

IntraWinding wrote ...

Thanks Stella. I'm wondering about:
that asbestos,
whether I can/should clean of the brown 'varnish' on the insides, and how
if the areas where copper shows through the silvery metal plating of the 'chimney' are a hazard to the oil (might catalyse it's cracking),
and what oils that scientific paper covers as they happen to use the same pump I have.

Any sign of Plazmatron, or should I PM him?

I can't comment on the asbestos, as my own pumps are the dinky 11cc and 13cc Edwards models, and mercifully don't have any. When you find out
how much a tiny bottle of Santovac 5 costs, you'll be wishing you had a smaller pump too.

There's no case for having brown goo, varnish, or other residues in the pump, which should be perfectly clean throughout. Residues, and even finger prints, are likely to start outgassing at the first opportunity. When you've reassembled it, it's a good idea to flush it through with anhydrous nitrogen.

I don't know anything about old oil formulations, but don't doubt that they have been superceded. But I'd advise against buying costly oils like Santovac 5 to start with, as a small mistake will ruin it. Much cheaper diff pump oils like Tetrasil 747 will be good enough for most purposes.

Plazmatron often comes here in the middle of the night, so you should drop him a line and ask his advice, as we're on the edge of the blind leading the blind here!

George Schmermund

Sat Nov 27 2010, 09:02PM

Registered Member #3304 Joined: Mon Oct 11 2010, 04:18AM
Location:
Posts: 9

This is probably the best collection of vacuum information available to the hobbyist. Just click on 'forums' and then click 'search'. Enter 'diffusion pump', choose 'vacuum technology' for the forum to search, and then click 'search'. This should keep you busy!

Ash Small

Sat Nov 27 2010, 11:00PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

The above mentioned website does contain a huge amount of information regarding vacuum techniques, I certainly agree with George on this point.

However, the people who run it do not take kindly to questions which are not directly related to fusors, and dozens of people have been banned this year alone from posting there because they were researching other vacuum/plasma related projects.

I would reccomend anyone who wants to learn about vacuum techniques to read the FAQ's etc there, but, be warned, if you ask questions not directly related to fusors you are likely to be banned from posting.

(The site is run by someone who actually believes an American invented television, maybe someone should suggest he reads this article:

I can't, as I'm one of the many who have been banned from posting there)

The site does contain a wealth of information, though.

Steve Conner

Sun Nov 28 2010, 03:05PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Well, I guess they are Philo Farnsworth fanboys. He invented the fusor as well as being America's claimed inventor of TV.

Everyone likes to think that one of their countrymen invented TV. If you asked me, of course I would say it was John Logie Baird. The truth is that a number of groups all over the world all came up with television-like devices around the same time.

Proud Mary

Sun Nov 28 2010, 04:17PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Steve McConner wrote ...

Everyone likes to think that one of their countrymen invented TV. If you asked me, of course I would say it was John Logie Baird.

1290960937 543 FT0 Mechanical Tv Receiver

1290960966 543 FT0 Mechanical Tv Receiver Photo

Personally, I think some people have invested Farnsworth with the same aura, the same mystique, that has accumulated around Nikola Tesla, both of whom I'ld characterize as interesting but minor inventors working far away from the great scientific debates and discoveries of their times, men with a whiff of the the unrecognised genius myth about them, like the tormented artist in his garret.

IntraWinding

Mon Nov 29 2010, 02:44PM

Registered Member #2261 Joined: Mon Aug 03 2009, 01:19AM
Location: London, UK
Posts: 581

Thanks folks. For now I'll be thoroughly cleaning and then polishing my diffusion pump and checking out the fusor web site.
I'm guessing that contamination deep within a diffusion pump is less troublesome than at its mouth.
I plan to try it with photocopier fuser silicone oil. It should be pretty low vapour pressure to keep the office workers healthy...

1 2 3 4 next last

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob