Weston (section 9.4.2, page 333/334) recommends 99% Ne, 1% Ar @ 30 - 40 Torr (about 4000 Pascals) for numerical tubes.
Nick On Oct 29, 2:49 pm, John Rehwinkel <[email protected]> wrote: > >> Yup, 2% Ar will work just fine. Striking voltage may be a little higher, > >> maintaining voltage should be about the same. > > > That's OK I guess, since I am not trying to optimize the mixture, I am just > > trying to get started. I have a 500V power supply @ 50mA available, that > > should work. > > Yeah, that should be plenty. Start with a largish anode resistor and reduce > it until the entire cathode is lighted (but avoid > getting over a few milliamps flowing). > > > What is the difference between a tack and a spot welder? I was going to > > look for a spot welder (although you can actually build them yourself). > > A tack welder uses a capacitor discharge for a quick weld. A spot welder > uses high current to weld. You can build > both of them yourself, and either should work fine for tube/nixie building. > The usual approach to an easy spot welder > is to remove the high voltage secondary from a microwave oven transformer and > replace it with a few turns of heavy > (8 gauge or so) wire. > > > For cathodes (and the anode mesh) I am planning to use 1.2mm stainless > > steel wire. > > Worth a try. I'd probably try nickel or iron, but almost anything should > work to start with. > > > But what should I use as a glas frit? > > Schott makes some solder glass that should be suitable: > > http://www.schott.com/ > > Alternatively, if you can get some large bore (20mm - 30mm diameter) lead > glass tubing, you should be able to seal > it directly to the stems using a crossfire or even a hand torch and some > care. You'll probably want to anneal it before > pumpdown. > > > And what kind of burner for melting the glass is appropiate? Propane and > > oxygen? > > The sort of tools used for neon glass work should be suitable: > > http://www.egl-lighting.com/cannonfires.html > > http://www.egl-lighting.com/torches.html > > A glass lathe would be ideal, but might be a bit expensive to start with. Or > you could try building your own (the concept > is simple, two chucks that rotate in synchrony). > > Propane and air is probably sufficient, but oxygenating it can get you some > extra heat. Some neon benders use the > sort of oxygen concentrator used for medical purposes to enrich the air > stream without needing bottled oxygen. > > > Thanks! But at the moment I will go for wire cathodes "National Union > > style" ;-) > > Makes sense. May I assume that the stems showed up? > > - Cheers, > John -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
