On 4/8/15 7:55 PM, Timothy Gilmore wrote:
Gary, I found a photo hosting site and posted some pics of the coil early on. http://tdg8934.smugmug.com/Sample-Gallery/ The fan is a 120 vac squirrel cage fan blowing on the tungsten spark gaps. However, I don't think its really that strong but I was told this is what was needed so I bought it. I don't have a lot of tools so I'm buying what I can to get it together quickly. The sucker gap you have sounds great but may be too complicated without the experience and materials to do this.
with a narrow gap like you have, there's not a lot of surface area, so you need decent air flow. If you have problems (e.g. coil performance starts to fall off after a minute or so, or the electrodes glow red), you can probably use some cardboard to increase the air speed in the gap area.
I use a parallel copper pipe gap, which has huge thermal area, and a very low speed fan keeps it cool.
The way to set the gaps is to connect just the NST (no primary, no caps, nothing else) and set them so they just fire (or don't fire if you're braver) at the max voltage you want to run at.The gaps on my coil are set about 1/4" or so apart. Using my 130vac 20A variac, it starts sparking on the gaps at about 1/2 to 2/3rds power of 120+vac (to 145vac "measured" max when 20A fuse blows before getting to this).
NSTs do not like overvoltage: they're designed for low cost and they don't spend anything extra on more insulation.
I did not know about how to set the gaps properly (i.e. as you said no caps) from the NSTs. As stated before I am moving in another week or so...so I can't make these changes till next month most likely. I will set the gaps to serial not parallel.
Parallel gaps are like one gap: one will almost always fire before the other, and once it does, there's not enough voltage on the unfired gap to fire it.
Series gaps have more loss. If it works ok with one gap, then just use it. _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla