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Registered Member #524
Joined: Thu Feb 15 2007, 03:28AM
Location: Sydney, Australia.
Posts: 21
A few months ago I started making some rough plans for a new small spark gap coil, as I felt I had been deprived long enough What I wanted to achieve was a small, lightweight and reliable coil that I can pull out every now and again for a run. I wanted it to be as hassle-free to set up as possible, and should need very low maintenance. I also wanted it to look nice and neat (so other family members wouldn't make me keep it out in the shed). My starting point was a 7.5kV 25mA NST I bought off the net, and a couple of wooden chopping boards from the local supermarket
I've been saving these little updates for a while, so here they are:
Cut the handles off two wooden chopping boards and rounded the edges to make it look like the handles were never there (which took ages). I cut some pine doweling into 125mm lengths and drilled some countersunk holes in the boards and screwed everything together with heavy duty galvanised screws, and it is as solid as a rock. It turned out to be heavier than I thought it would be, but that's no problem.
Here's a couple of pics (they're a bit dodgy, but you get the idea). Theres a bit of lens distortion which makes the back left doweling support look crooked, but it really isn't.
Registered Member #524
Joined: Thu Feb 15 2007, 03:28AM
Location: Sydney, Australia.
Posts: 21
The perspex arrived and I've drilled a 60mm hole in it and another one on top of the frame (so thay they'll line up when the perspex is placed on top of the frame.) The hole is for the secondary coil to go through so it will be able to sit nice and solid in the frame, and can also be removed easily if need be. I've also cut the PVC for the secondary coil, and spent about 2 hours winding the 0.2mm copper wire. There are approximately 1040 turns in total. Here are a few pics:
Registered Member #524
Joined: Thu Feb 15 2007, 03:28AM
Location: Sydney, Australia.
Posts: 21
Hazmatt_(The Underdog) wrote ...
Use the Attachments thread to add pictures, then you can post all your pictures at a later time in the same thread. Otherwise, good job!
Thanks Hazmatt, I've updated my original posts with proper linked thumbnail pics.
uzzors wrote ...
Wow, thats clean. Looks good.
Thanks uzzors. Yeah the thing I'm trying to do with this coil is make it as nicely made as possible so a) I'll be allowed to keep it in the house, and b) Will hopefully be something cool to look at when it is and isn't powered up.
Registered Member #524
Joined: Thu Feb 15 2007, 03:28AM
Location: Sydney, Australia.
Posts: 21
OK, I've finally gotten around to wiring everything up and giving it a test run. It appears to work well, with streamer length between 30 and 40cm. It does appear that I'll need a toroidal topload, as the spherical one is a bit lacking in terms of shielding. Anyway, here's a couple of pics and a link to a video taken shortly after first light.
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Small SGTC.
What I wanted to achieve was a small, lightweight and reliable coil that I can pull out every now and again for a run. I wanted it to be as hassle-free to set up as possible, and should need very low maintenance. I also wanted it to look nice and neat (so other family members wouldn't make me keep it out in the shed). My starting point was a 7.5kV 25mA NST I bought off the net, and a couple of wooden chopping boards from the local supermarket 
