Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Cheap Vaccuum Gear
Date: Jan 12, 1:25 am
Poster: Richard Hester

On Jan 12, 1:25 am, Richard Hester wrote:

First of all, get to know your local surplus outlets/junk stores/liquidators/junkyards. This includes used machine tool outlets, who sometimes also carry used vacuum pumps and other relevant gear. That's how I got mine. :-) I've gotten some tremendous dime-on-the-dollar bargains that way on things I wouldn't even consider at full price (valves, regulators, ionization gauge controller, baratrons, the list goes on...). Depending on what part of the country you're in, the pickings can vary. I live in Silicon Valley, so the pickings are pretty good.

I might get singed around the edges for saying it, but Ebay can be a very useful source if you are careful. Notable purchases of mine include 2 working thermocouple vac gauges, gas regulators, YAG laser rods, HV caps, NaI scintillator, cross purge assy, vacion controller,1000X scope probe for pulse work. Since you are seeing offerings from folks around the country, you see things that might take you forever to score locally.

If you're not up to learning TIG welding to put your own metal chamber together, you might want to try doing a fusor in a section of pyrex process pipe. This stuff is used by laboratories, chemical factories, and food processing concerns, and has has molded-in o-ring receptacles on the ends that allow one to blank off the tube with a simple clamp (available as an accessory) an o-ring, and a metal plate. Basic shapes like straight sections, tees and crosses are available in sizes up to at least 6" diameter. If you use a solid outer grid (ss pipe) you may be able to get around the e-beam softening problem that plagues folks who try fusors in bell jars. The walls are thick, so the pipe is also pretty rugged.

If you can get a sizable conflat or LF style tee fitting (6" or bigger), this can also be used as the basis for a fusor chamber. A lot of times, the tees seem to be easier to come across than the blank flanges to finish them...

Also, try scouring the web for places that sell used fittings. Use search parameters like "conflat", "claw clamp", "used vacuum", etc.

Most importantly, patience and persistence pay off. I've been at it a year or so now, and am finally getting together a critical mass of gear for fusor work (but not before my copper vapor laser).

Richard Hester

>I've been poking through various online suppliers of vacuum equiptment, both premium places like Leskers and less expensive, and the cost of all the necessary gear for a proper vacuum system is dizzying -- my rough estimate is on order of $5k-$10k doing it that way. It's clear that doing it that way is impractical for all but the richest amateurs.
>Can Richard or some of the other people here who have built fusors give some pointers on how and where to obtain inexpensive vacuum gear and what substitutions can be made using ordinary parts instead of their vacuum rated counterparts?