Well it’s about time I got around to it, it’s over 12 years now since I first came across the idea and after all scratchbuilt lasers just aren’t cool anymore, in fact once something becomes work it tends to take the fun right out of it – remember that next time you want that ‘dream job’. It’s not so much fun after 10 hours covered in oil and metal oxides replacing the turbopump – again – as the first replacement was a ‘good used’ that wasn’t – these are real pumps the size and weight of a car engine, not the little 50l toys ;).
Anyway I’m busy accumulating the bits needed to build a small round glow light AKA fusion reactor, mostly the Neutron detector frontend and some better vacuum plumbing. Trying to decide if I should splash out on a small turbopump or just buy some silicone oil for the diffusion punp. Bits like that….
Once something interesting gets put together I’ll post more.
This Post Has 2 Comments
Ron Soyland22 Jun 2012
What in the world are you using in the diffusion pump if not silicone oil? I had thought that by now everyone has switched over. I can’t imagine you using octoil! (see my website on diffusion pumps on why!) Use plain DC704 and you will easily get to the low 10-6 range with no bakeout needed. This is plenty low enough to outgas the system for a fusor.
When buying the 704, shop around. There are scammers selling 50ml for 50 bucks! You can get a 500ml bottle for around $110, and that will last a lifetime. It doesn’t go bad like hydrocarbons or octoil.
Tony22 Jun 2012
I wouldn’t consider using anything else, the choice was really either buy some oil or wait for a cheap turbopump – around here they’re not common and seem to have dried up altogether recently so I’ll probably just use the diffusion pump, last time I checked the cheapest 704 I could find here was £27.50 plus £17.50 post for 250ml, plus 20% tax.
Your glassworking/tubemaking videos are great BTW,