Search found 369 matches

by Quantum
Tue Dec 29, 2009 2:41 pm
Forum: Vacuum Technology (& FAQs)
Topic: Re-building MKS mass flow controllers
Replies: 3
Views: 2207

Re: Re-building MKS mass flow controllers

<t>I'm assuming, for now, that it is either the electronics or the solenoid that are malfunctioning.<br/> <br/> The manual says these require +/-15 volts and +5 volts, I'm wondering if the +/-12 volts from an ATX power supply will be sufficient for the +/- 15 volt supplies?<br/> <br/> It will go dow...
by Quantum
Tue Dec 29, 2009 1:22 pm
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Self-synchronous out-of-phase beam behaviour due to chamber contaminants.
Replies: 9
Views: 4099

Re: Self-synchronous out-of-phase beam behaviour due to chamber contaminants.

<t>Every system has a 'natural frequency', Doug, It would be irrational to assume a fusor is different.<br/> <br/> When the oscillations of the D ions correspond with the fusion cross-sections, more fusion will be observed. This will depend on fusor geometry. Larger ions will also cause neutral Ds t...
by Quantum
Tue Dec 29, 2009 12:59 pm
Forum: Vacuum Technology (& FAQs)
Topic: Anti-seize compound for 1/4-28 threads
Replies: 19
Views: 5873

Re: Anti-seize compound for 1/4-28 threads

Chris, the reason they sell silver plated bolts is to prevent seizing.

Stainless-stainless is notorious for galling, even at moderate torques. stainless-aluminium can also seize.

It's always advisable to use anti-seize of some sort where possible.
by Quantum
Mon Dec 28, 2009 8:03 pm
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Self-synchronous out-of-phase beam behaviour due to chamber contaminants.
Replies: 9
Views: 4099

Re: Self-synchronous out-of-phase beam behaviour due to chamber contaminants.

<t>'Tuned frequency'.....I believe all fusors will have their own 'tuned frequency', and that this explains this phenomenon.<br/> <br/> (personally, I'd prefer less rant, and more facts per paragraph, but who am I to comment?)<br/> <br/> Any 'system' of this type will have it's own 'natural frequenc...
by Quantum
Mon Dec 28, 2009 6:42 pm
Forum: Vacuum Technology (& FAQs)
Topic: Anti-seize compound for 1/4-28 threads
Replies: 19
Views: 5873

Re: Anti-seize compound for 1/4-28 threads

<t>Using different materials is a good way to avoid seizing (galling), but permalon isn't messy, you apply it with a paintbrush, and allow it to dry before assembly.<br/> <br/> It is one of only two lubricants we use inside vacuum chambers. The other is Everlube, which we use for bearings, and which...
by Quantum
Mon Dec 28, 2009 4:53 pm
Forum: Vacuum Technology (& FAQs)
Topic: Anti-seize compound for 1/4-28 threads
Replies: 19
Views: 5873

Re: Anti-seize compound for 1/4-28 threads

<r>We use Permalon M anti-sieze inside chambers at work.<br/> <br/> Once dry (five to ten minutes), it only consists of carbon, and is good for 2000 degrees F when no oxygen is present.<br/> <br/> It is definitely suitable for flange bolts, and seems ideal for stainless-stainless threads.<br/> <br/>...
by Quantum
Sun Dec 27, 2009 2:04 pm
Forum: Vacuum Technology (& FAQs)
Topic: 'Throttling' a turbo pump, without a pump-to-chamber valve.
Replies: 9
Views: 2631

Re: 'Throttling' a turbo pump, without a pump-to-chamber valve.

Yes....I was thinking maybe you could use magnets to open/close an aperture, rather than a bellows, for example?

EDIT: if it was visible through the wall of your glass chamber, you would have visual confirmation of the size of opening.
by Quantum
Sun Dec 27, 2009 1:17 pm
Forum: Vacuum Technology (& FAQs)
Topic: 'Throttling' a turbo pump, without a pump-to-chamber valve.
Replies: 9
Views: 2631

Re: 'Throttling' a turbo pump, without a pump-to-chamber valve.

A part-open gate valve will allow molecules to pass in both directions.

All you are doing is restricting the flow.
by Quantum
Sun Dec 27, 2009 10:24 am
Forum: Vacuum Technology (& FAQs)
Topic: 'Throttling' a turbo pump, without a pump-to-chamber valve.
Replies: 9
Views: 2631

Re: 'Throttling' a turbo pump, without a pump-to-chamber valve.

A gate valve here doesn't need to be gas tight, Chris, it just needs to 'throttle' the flow, so you should be able to improvise.