Search found 211 matches

by prestonbarrows
Sat Jun 23, 2018 3:15 am
Forum: New User Chat Area
Topic: Is baking worth it?
Replies: 16
Views: 3139

Re: Is baking worth it?

If you have an RGA, you are miles beyond most folks on here. You should notice, as it seems you have mentioned, that the H2O and other volitile peaks spike up when you spark a plasma. This is due to the surface layers adsorbed to the vacuum chamber getting pounded with enough energy thorugh ion bomb...
by prestonbarrows
Sat Jun 23, 2018 3:05 am
Forum: New User Chat Area
Topic: Use of Swagelok needle valves
Replies: 24
Views: 4242

Re: Use of Swagelok needle valves

You can find 0-10 SCCM mass flow controllers on Ebay if you wait long enough. Most of my fusion is done in the 4-6 SCCM region. Then again, I'm not using expensive bottled D2. But as I recall, when Richard tried to be too miserly with his D2, he did not get really great neutron numbers. It is fairl...
by prestonbarrows
Sat Jun 23, 2018 3:01 am
Forum: Images du Jour
Topic: Deposition within a fusor
Replies: 4
Views: 2560

Re: Deposition within a fusor

My question was, were the deposition patterns you are reffering to a 'positive' pattern (the outlines of the grid aligned with lines of the grid material deposited on the outer chamber wall) or a 'negative' pattern (isolated spots of the grid mateial aligned with the voids between the central grid o...
by prestonbarrows
Sat Jun 23, 2018 2:53 am
Forum: New User Chat Area
Topic: Usable transformer
Replies: 13
Views: 3012

Re: Usable transformer

Would there be anything I could do to increase the stability of the output... In general, you want a resistance in series with the output and a capacitance in parallel to earth. The series resistance prevents large currents and the parallel capacitance provides a 'battery' to chug through any trans...
by prestonbarrows
Sat Jun 23, 2018 2:49 am
Forum: Images du Jour
Topic: First Plasma
Replies: 11
Views: 2634

Re: First Plasma

That vacuum chamber was one that I was just using for plasma generation. I am going to purchase a 2.75 inch conflat cross for the actual chamber with the proper conflat fittings. Vacuum systems are a 'weakest link' situation. It dosen't matter if you have a vacuum chamber from CERN and a vacuum pum...
by prestonbarrows
Sat Jun 23, 2018 2:30 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Build a HV bias meter for free.
Replies: 9
Views: 3554

Re: Build a HV bias meter for free.

Once the failure rate of an insturment approaches (inevitably in your mind) unity, the effective accuracy (for all previous times) approaches zero.
by prestonbarrows
Tue May 22, 2018 4:20 am
Forum: Images du Jour
Topic: Deposition within a fusor
Replies: 4
Views: 2560

Re: Deposition within a fusor

Have you fooled around with srim for these materials, energies and currents? Do those sims match up with what you see?

Are you saying you saw a 'positive' grid pattern on the walls (lines) or a 'negative' one (spots)?
by prestonbarrows
Tue May 22, 2018 4:06 am
Forum: New User Chat Area
Topic: Usable transformer
Replies: 13
Views: 3012

Re: Usable transformer

In general, flyback topologies are not the best for plasma applications. Especially poorly regulated chineesium perfboards. These are barebones and stripped down for cost. At best you can hit their ratings into a stable resistive load. Or at best a CRT or flouro bulb. Beware how they react with the ...
by prestonbarrows
Tue May 22, 2018 3:46 am
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum Pump Issues
Replies: 8
Views: 1737

Re: Vacuum Pump Issues

A bit hard to tell from your pic but the oil through viewport should look clear and translucent(like maple syrup) not milky or opaque (like caramel). Opaque means air bubble or water emulsion. If it gets bad, only solution is to flush the oil. You should do initial tests with the pump deadheaded to ...
by prestonbarrows
Tue May 22, 2018 3:07 am
Forum: Images du Jour
Topic: First Plasma
Replies: 11
Views: 2634

Re: First Plasma

What kind of vacuum gauge were you using before it broke? What makes you think the gauge is broken? What makes you think the gauge is leaking oil into the vacuum?

What type of pump are you using?