Search found 1288 matches

by John Futter
Tue Jul 17, 2018 10:40 am
Forum: Images du Jour
Topic: Killer deal on a GeLi gamma spec
Replies: 5
Views: 267

Re: Killer deal on a GeLi gamma spec

you could try redrifting the GeLi crystal to get it to work again
But I think you will wane on keeping it cool
so good dewar and electronics
by John Futter
Sun Jul 15, 2018 1:15 am
Forum: New User Chat Area
Topic: Working Diffusion Pump?
Replies: 7
Views: 307

Re: Working Diffusion Pump?

Okay you all have not been doing much reading on this site We prefer that you upload photos resized resampled to 1024x 768 pixels max ( note you are not paying for server space) the reason we do this is most external links dissappear in time so this entire post becomes meaningless with a magic black...
by John Futter
Sun Jul 15, 2018 1:10 am
Forum: Please Introduce Yourself
Topic: Greetings from Rhode Island
Replies: 2
Views: 114

Re: Greetings from Rhode Island

Hi guys I think you all should introduce yourselves individually pronto as per the rules which you all seem to have overlooked. If you all do this then your group effort sign in might continue. Ehen each of you do the introduction please make sure to link to this group other than that welcome ps rea...
by John Futter
Wed Jul 11, 2018 7:05 pm
Forum: Vacuum Technology (& FAQs)
Topic: Tips on Roughing Pressure
Replies: 2
Views: 210

Re: Tips on Roughing Pressure

What does the manual for your pug say as to the reccommended oil? Is this a direct drive or pulley driven pump? A pic of pump would be nice Have you rung Mobil's tech department to check whether the mobil oil is actually a replacement for the reccommended oil? Have you run the pump with gas ballast ...
by John Futter
Fri Jul 06, 2018 6:47 am
Forum: Books & References
Topic: Answer keys w/ explanation?
Replies: 19
Views: 847

Re: Answer keys w/ explanation?

Rich
if all is right who would ask this question of a 14 year old
ammen is learning well done and help will come

Ameen do not take us for a ride
the gods might become very angry
by John Futter
Thu Jul 05, 2018 5:10 am
Forum: Please Introduce Yourself
Topic: Good evening from Maisons-Alfort
Replies: 3
Views: 267

Re: Good evening from Maisons-Alfort

Welcome Patrick you will find at the top of each sub forum on this site the FAQ section a wealth of information there you are lucky to be retired I'm in New Zealand and have 3 years to run to 65 when I might first be able to retire And I also work in a similar nuclear indusrty allthough we are suppo...
by John Futter
Sat Jun 30, 2018 7:23 pm
Forum: Vacuum Technology (& FAQs)
Topic: Back-Streaming Diffusion Oil
Replies: 10
Views: 656

Re: Back-Streaming Diffusion Oil

What I do not understand is low viscosity cold diff pump oil is like treacle you did not say which oil you have DC704 or DC 705 I doubt you have Santovac due to cost. Diff pump oil charge is critical if it says 75mls then 75 mls it is, it does not work better with 100mls in fact it will tend to burp...
by John Futter
Fri Jun 29, 2018 8:07 am
Forum: Vacuum Technology (& FAQs)
Topic: Back-Streaming Diffusion Oil
Replies: 10
Views: 656

Re: Back-Streaming Diffusion Oil

yes the oil will move to the roughing pump if the diff pump is not part of a system as in your photo. you must have the diff pump sealed off at its top opening not aluminium foil. the back ing pump needs to be pumping in the molecular flow regime not bulk flow. Bellows tube is not my favorite for ba...
by John Futter
Fri Jun 29, 2018 8:00 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Vacuum Chamber Construction
Replies: 11
Views: 1871

Re: Vacuum Chamber Construction

Toe clamps directly to mill slide bed
t bolt through the hole in the top with machined aluminium disc to fit hole now held top and bottom you will need to offset mill head to correct angle to bore hole.

enjoy
by John Futter
Fri Jun 22, 2018 6:33 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Ballast resistor construction
Replies: 11
Views: 890

Re: Ballast resistor construction

Dan Do not put those resistors in the tube the ozone (read live ions) will build up and kazap see this post I did a few years ago very similar resistors and corona rings at top and middle reduced corona current to acceptable about 3 quarters of the way down the post http://www.coultersmithing.com/fo...