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.
Hello!
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.
ron
Hi,
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,
Tony.