Search found 461 matches

by ian_krase
Wed Jul 25, 2018 4:42 am
Forum: New User Chat Area
Topic: Fusor Plan
Replies: 9
Views: 1239

Re: Fusor Plan

1. It looks like you have a pretty narrow pipe between the diffpump and the chamber. Diffusion pumps are the large diameters that they are for a reason, and the valve doesn't help. This may make initial pumpdown a lot slower. (That isn't to say this is a showstopper by any means, just that it's less...
by ian_krase
Mon Jul 23, 2018 7:24 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: RF excited ion sources
Replies: 9
Views: 5111

Re: RF excited ion sources

What was the "better cable"?

Did you do anything to ignite other than apply RF? Can you ignite with an NST dc discharge for example?


What can you do with 25-50 watts?
by ian_krase
Sat Jul 21, 2018 11:50 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: In-Vacuum Electrical Connectors
Replies: 2
Views: 856

Re: In-Vacuum Electrical Connectors

It seems like this is almost always going to be screws and nuts for the low-budget. Accu-Glass has many options including circular "C-sub" connectors for multi-pin instrumentation and larger pin-and-sleeve connectors. However they are dear. If you are OK with brass in your chamber, you have many opt...
by ian_krase
Sat Jul 21, 2018 11:45 pm
Forum: Announcements and Site Administration Topics
Topic: How did you find our Fusor forum?
Replies: 8
Views: 978

Re: How did you find our Fusor forum?

Is it possible we could transfer, say, everything older than 2016 to a static site and then reboot the forum? If I'm not mistaken, static sites are cheap. Is there a way to limit search-engine indexings to once every few weeks or something? A little transparency about what the costs are plus a reque...
by ian_krase
Fri Jul 20, 2018 4:52 am
Forum: Announcements and Site Administration Topics
Topic: How did you find our Fusor forum?
Replies: 8
Views: 978

Re: How did you find our Fusor forum?

I'm pretty sure I found it by google, and by googling specific non-fusion-related info about vacuum tech.
by ian_krase
Mon Jul 16, 2018 12:29 am
Forum: Announcements and Site Administration Topics
Topic: Sunnyvale Mini Meetup -- August 11
Replies: 5
Views: 992

Sunnyvale Mini Meetup -- August 11

Since my attempt yesterday got good response but only one person actually came: I propose that those of us who live in the south San Fransisco Bay Area have a mini-meetup in Sunnyvale after the Sunnyvale Electronics Flea Market on August 11. As the flea market winds down we would meet up at a nearby...
by ian_krase
Sun Jul 15, 2018 12:16 am
Forum: New User Chat Area
Topic: VACUUM CHAMBER
Replies: 5
Views: 682

Re: VACUUM CHAMBER

Glass is risky in vacuum because its brittle, but in general vacuum forces are not overwhelming to a chamber that is either properly stiffened or just thick-walled. 1/8th inch is thicker than needed for the typical vacuum hemisphere chamber, 1/16th inch (1.5 mm) is enough. However, Plexiglass will l...
by ian_krase
Tue Jun 26, 2018 8:25 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Couple of questions
Replies: 39
Views: 6275

Re: Couple of questions

Personally, I STRONGLY recommend that you put plenty of work into excellent grounding. Get some thick-ish copper wire and connect all the things in a star network. Even if you don't have an actual faraday cage, making sure that you'll inadvertantly touch or get neara grounded conductor rather than a...
by ian_krase
Mon Jun 25, 2018 7:33 am
Forum: New User Chat Area
Topic: Anyone recognize what type of flange this is?
Replies: 5
Views: 1114

Re: Anyone recognize what type of flange this is?

Yeah, that definitely looks like a sanitary ("milk pipe") flange to me.

I have seen them used in vacuum work in rare situations, mostly in things like the separation to open up foreline traps for replacing the media.
by ian_krase
Thu Jun 14, 2018 3:50 am
Forum: New User Chat Area
Topic: Diffusion pump power wire convert
Replies: 7
Views: 1365

Re: Diffusion pump power wire convert

To slightly elaborate on "makes life easier for switches":

Since AC is going around zero volts and zero amps 50-60 times a second, it's much easier to stop an arc.