A while back, I posted a rough fusor budget (vacuum chamber parts alone) for an 8" diameter spherical chamber based on claw clamp ISO LF 200 flanges, and J.G. Braun ss hemispheres. One of the reasons I posted this was that I thought that the $100 each new price for the LF200 weld flanges was unprecedentedly low for any flange that size, $50 less than from other vendors for the same flange, and less than 1/2 the price of conflat flanges of comparable size. The price of the captive o-ring seal sops up some of the price advantage, but it is reusable.
The price for a 6" system looks even better - the flanges go from $100 apiece to $67, the captive o-ring goes down to $40, the hemispheres are 33.20 apiece, for a total price of chamber parts (all new) of 363.90. Sharpe Industries has 6" SS hemispheres priced at 18.80 apiece. I would enquire about the material thickness before I rushed out with my credit card, but it looks like a sweet deal... With the Sharpe hemispheres, the total price of new parts (chamber parts alone, you figure out how to fab it) goes down to 335.26.
Richard Hull has pointed out (justifiably) that this is just the beginning of expenditures if one wants a real rootin' tootin' neutron producin' fusor. I've probably spent 3-5k on vacuum, high voltage, and other incidentals so far and haven't seen neutron one yet, though I think I'll be ready when they do show up. What's my point? If you don't have your own machine shop, and haven't run into that once in a lifetime surplus/hamfest deal, you will need to spend some money to get what you need for a chamber. Some casting around can save you loads on the stuff you can't avoid buying with real money. The prices I mention above were discovered with a couple of hours of banging around on the net using the BullsEye search engine. It may be possible to do better, I don't know. I would use the prices mentioned above as starters and get creative about scrounging around for the incedentals. Large flanges are pretty scarce on the surplus market, but I have found a lot of the smaller conflat and KF components needed for ports and such on Ebay and at local surplus emporiums for dime on the dollar (or less). Just finding a viewport ($89 new price) for a low price can whack down the total parts prices I mention above by a very large fraction. Make friends with somebody who has a TIG setup, or maybe take a welding class and make your fusor your class project. Visit junk yards, metal recyclers, go dumpster diving!
Happy Scrounging...
P.S. Extra brownie points to the first guy who gets neutrons out of an old stainless steel pressure cooker - who says it has to look professional?
Created on Tuesday, April 03, 2001 2:38 AM EDT by Richard L. Hester