SGTC finally working

McFluffin, Mon Jun 05 2006, 12:37AM

Around 3 or 4 years ago, I saw Tesla coils online and thought it would be cool to build one. Although built in less than a year(this project taught me how to use tools, so I had to wait until my dad had free time to show me how to do things), my dad never wanted me to turn it on. I did some other things to keep busy. Around a month ago I finally got cleared to try and it didn't work. Tested the capacitor(it was home made), and discovered that it didn't work. So, I got some of these:

which wasn't bad for 16 bucks to at least try first. I put them in strings of 12 and put two of those in parallel to get an MMC. I turned it on, and now I am able to draw a 2 foot spark off of it(but only a couple of strikes to the rod). Now I guess I'll have to get into tuning it. Heres a pic of the coil set up:

The two black things in front is my spark gap. Behind that is my 10.5kV NST rated at 30mA.
The tank cap:

Its 14.4nF rated at 19.2kV which should keep them at a long life. It has to be tuned still, but I'm happy that things are at least making some cool sparks. Let me know what you think!
Edit:
Turned it on at night. Things went pretty well, so I added another capacitor string which seemed to make things a little better. I then added a breakout point, and that made operation a lot more stable, but I am still having problems with everything suddenly stopping. If I turn down the variac, and then put it up again, things can intermitantly work. What causes this? I added my rotary spark gap in(my avatar), and it made things pretty good. When I turned things off, I was getting 4 inch streamers. Its pretty neat, but I am sure that I could get things a lot better. Without the rotary, things were pretty stable, but after it was added things got a lot worse. Decreasing electrode distance on the safety gap seemed to help with the stability as well as adding the breakout point. Tried to take a picture, but my digital camera wasn't very happen even 6 feet or so away.