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: OT -- good price on vacuum gear?
Date: Jan 25, 6:15 pm
Poster: Pierce Nichols

On Jan 25, 6:15 pm, Pierce Nichols wrote:

Short comment -- the reason I'm spending so much time lately talking about vacuum equipment rather than strictly fusor stuff is I am working up a design and starting to accumulate necessary items, and most of my questions are directed toward that. I think it's mostly related because any fusor is a vacuum project as well. If ppl think that it is a distraction, I can take it to private email.

>30 l/s is an awfully small pump for those big bucks. As it is a nice Varian unit with magnets and if it is clean and not all clogged with crud. The price is not outrageous, just stiff.

The reason I was considering it is because it is less than a third of the duniway rebuilt cost for a similar unit (~$1k). It's also from a small but reputable laser company in Cambridge (parallax) shedding excess equipment through their website. It's not eBay, and it's not a fly-by-night surplus house, so it's prolly a clean unit.

>The controller is un-necessary if you have any HV power supply construction skills. The beauty of having a proper controller is that most include a vacuum gauge readout based on the action of the pump in use.

I realize that. A couple of calls to Varian could prolly elicit the calibration curves they use to provide that vacuum readout -- I bet it has something to do with the voltage required to maintain the spec operating current. Given the curves a little microcontroller like a PIC can provide a digital readout through a lookup table.

>The bottom line,..... if I had to have a nice ion pump right now, had $300 to spare, and was assured of its cleanliness, I would probably go for it.

I don't need it right now; I was wondering if it was enough of a steal to justify going after it before I have a lot of other necessary equiptment. If it's a stiff price I'll just wait and spend the money on a couple of valves. On that note, what is the fair price for 2.75" CF and 1.33" CF manual valves, both bakeable and non? Assuming clean and working, of course. What's the fair price for 2.75"CF & 1.33"CF flanges, nipples, tees, and crosses?