Tesla Coil Build Thread

[Fiddy]

Haha, a fab PCB bridge? Maybe if we find a place that can do more than 1oz Cu per layer. Idk if any standard traces will will handle >500W in CW SSTC operation.

In professional setting they put power traces on bottom layer and leave bottom mask off then wave solder the board so the trace gets built up will several mm thick of solder. I don't have a wave solder station, haha.

Plus, we'd have to beat EVR's price point of $40 per board and his handles CM 600s (but not 3KW CW, haha).

Hmmm what if we use both top and bottom layer of a board for carrying the power?

 

[The Lightning Stalker]

I've never tried it, but it might be possible to coat the traces with solder using a heat gun and some care.
It might be doable with a blowtorch, but you would have to keep it moving quickly at all times.

It would have to be done before the parts were put on since we're not using surface mount (designed to
take the heat). Then the holes would be cleared and the parts soldered in.

 

[Sigurthr]

Split (parallel electrically) traces result in unbalanced inductances which can spell disaster in transient conditions. Bridge design is a bit of a nightmare, hehe. I'd say 200W per ounce of copper is a good safe limit. Another problem is the voltage standoff needed; during pulsed operation when an off period is reached and current in primary is high (hard interrupter switched) you get a huge voltage spike. I always try for 1kV standoff for 120V operation.

 

[Speedy78]

The traces on the bottom of the oneTesla had to be coated up with solder. Wasnt too hard. Some people layed down thick copper wire in the same orientation and flat soldered it into the trace. Not sure if thats a viable option.

 

[Sigurthr]

Yeah that's a workaround but then what's the benefit over the DIY PCB I had planned? Lol.

 

[Fiddy]

hmm doesnt seem worth it.

When i was fne tuning my microbrute, the only sure way i found to know which way to tune it was looking at how long the coil would ring-down for (with a scope), is that a good way to fine tune the system?

 

[Sigurthr]

You mean other than matching the resonant frequencies? Hehe, yeah you can watch the peak currents with a current probe and tune for highest primary or highest secondary base current.

 

[Speedy78]

Clean looking silk screened pcb. Though havibg a little custom hand made parts would be fun IMO. Hardest part of this whole coil will be finding a spun toroid that keeps this whole project cheap.

 

[Fiddy]

You mean other than matching the resonant frequencies? Hehe, yeah you can watch the peak currents with a current probe and tune for highest primary or highest secondary base current.

haha im very close to resonance, just fine tuning .1 of a turn on the primary at a time.

Ive just got the scope leads in the vicinity of the coil when its running, looking at the voltage being induced into the scope leads i can see the coil ringing down, if i fine tune primary turns so that i get a the longest ring-down on the scope, that should be the best resonance for it?

 

[Sigurthr]

Yeah, I can't help there, sorry. You'll need a breakout point though, might I suggest one of Fiddy's? Hehe.

I've done tons of hand made circuits and while they're novel at first and a chip on your shoulder, unless it is a circuit you designed they just fall flat of something professionally done in the end, especially if it is something that will get a lot of use.

 

[Sigurthr]

Ring up and down times are a function of tank Q, iirc. Current measurement is the way to go once you're very near resonance. You should ideally pick a pole, but that is a truly advanced topic and one should consult Mr. Ward and Mr. Conner (the experts) for that info.

 

[Fiddy]

Clean looking silk screened pcb. Though havibg a little custom hand made parts would be fun IMO. Hardest part of this whole coil will be finding a spun toroid that keeps this whole project cheap.

Hmmm depends how big, ive got 4", 6" and 8" currently

Ring up and down times are a function of tank Q, iirc. Current measurement is the way to go once you're very near resonance. You should ideally pick a pole, but that is a truly advanced topic and one should consult Mr. Ward and Mr. Connor (the experts) for that info.

Hmmm must i ask them on 4hv?

 

[Speedy78]

Where do you get your toroids from?

 

[Sigurthr]

Hmmm must i ask them on 4hv?

While in the little conversation I've had with them they were exceptionally helpful and polite, the culture there is not as... forgiving to newcomers who haven't done tons of research as we are here on LPF. If I were in your shoes I wouldn't want to impose with a direct question.

I've dug up a pertinent thread for you. I *think* you can view it without being a member. Forums / Tesla Coils / DR tank impedance, lower vs. upper pole - 4hv.org

Let me know if you can't see it.

 

[Fiddy]

4" - Aluminium Toroid for Use With Tesla Coils and Other HV Electronics

6" - 6" x 1 3 4" Toroid for Tesla Coil Marx Generator Quality Spun Aluminum Polished | eBay

8" - 8" x 2 34" Toroid for Tesla Coil Quality Spun Aluminum Micro Brushed Finish | eBay

12" - 3" x 12" Toroid Tesla Coil for Neon Transformer | eBay



I think im gunna change my Onetesla toroid to the 8" one above, the onetesla toroids are shit.

Putting the 4" one on my nano spark gap coil.

 

[Speedy78]

I bet thay would drop my secondary resonance a good bit. Has a lot more surface area. Would I be able to build a larger coil with this new board and utalize that 12 inch one?