DC Tesla Coil project - help!

[Gomo]

Hello dear reader,

 

I've decided to build a small DC tesla coil as my next project (not HVDC). Now the problem is, I cannot find decent / reliable information regarding this subject. Most of the tutorials are made just for that radius X with X many winds and "that voltage" .. you get the point. Basically I was planning on using 32V / 1.5 A power supply, 200 meters of this wire and wind it around ⌀5cm (~ ⌀2 inch) & 20cm (7.8 inch) long pipe. I've got no idea about the thickness and amount of winds that should be used on the primary nor the circuitry (what transistors / capacitors etc. to use), or schematic for that matter. So if you have any experience & are willing to help, I'd greatly appreciate it! Cheers!

[MarcoTexture]

Hi, I've built 2 Solid State Tesla Coils (SSTC) last year and it was really not that hard to do. It requires patience. thats all.

Now as for the parts. the 30 AWG is fine. Basically anything from 28 up to 36 will be sufficient of a coil that size. I'd aim for a minimum of 800-1000 turns on the secondary and up to 3000. ~20cm height x ~ 3.5-5 cm is fine. and For that height and diameter, the 30 AWG is really a good choice.

As for the primary, well you need to test it out yourself and see what works best but it is usually 4 turns to 7 turns max for a tesla of that size. it depends on the resonant freq of your coil+top load.

BTW don't use a card board pipe, go for a pvc pipe instead.

And as for the circuitry. there are many on the internet. but I recommend going for a slayer exciter design. all you need is a good transistor (buy bunch of them coz you'll burn a few in the tuning process). + a heat sink. some caps too, some 1000-2500uF as tank caps across the primary and maybe couple of the smaller ceramic ones for decoupling and such. basically what you have laying around.

The last important thing is a good power supply, something like this is more than enough https://www.amazon.com/Docooler-Voltage-Transformer-Switch-Display/dp/B00SWSWXAC/ref=sr_1_8?ie=UTF8&qid=1492898629&sr=8-8&keywords=48v+led+driver.

 

 

There are many guides online on how to do it, IMO the best one I found is this guy.

http://www.instructables.com/id/Easy-SSTC-Slayer-Exciter-On-Steroids/

You'll find some detailed info about the type of transistor, caps...etc etc.

Good Luck & Cheers.

[Gomo]

@MarcoTexture Alright, thanks for all the info! I'll look up what I can find / purchase and will post updates. This helped a lot, thank you for taking the time!

[MarcoTexture]

You're most welcome. Lets us know the results.

[Gomo]

Well, I finished winding up the coil, and the numbers don't really match .. I got ~ 437 turns / 24cm tall coil. Am I doing something wrong? Should I do multiple layers?

Here are the pictures:

 

And here's something that worries me.. Is it bad? will it affect the performance?
      

[Gomo]

Uhm, anyone?

[NoxiousOdor]

On 4/23/2017 at 6:14 AM, Gomo said:

Well, I finished winding up the coil, and the numbers don't really match .. I got ~ 437 turns / 24cm tall coil. Am I doing something wrong? Should I do multiple layers?

Here are the pictures:

 

And here's something that worries me.. Is it bad? will it affect the performance?
      

That won't make a noticeable difference. Yes it is good to get it neat and tidy and in particular uniform, but having an irregularity here and there is okay. There are plenty of other variables that would make a more significant difference. I forget the name of the group but there is a company that does music with two huge coils that are about 15 feet tall and they mentioned this very thing in one video. In short it is good to try and get it as nice as you can but it doesn't need to be perfect

[NoxiousOdor]

Just now, WhisperingKnickers said:

Well, I finished winding up the coil, and the numbers don't really match .. I got ~ 437 turns / 24cm tall coil. Am I doing something wrong? Should I do multiple layers?

I don't know about this though

[Gomo]

@WhisperingKnickers Alright, thanks! Uhm, @MarcoTexture could you explain how you got to that high number of winds with this specific wire & hight?

[MarcoTexture]

On 5/2/2017 at 7:18 PM, Gomo said:

@WhisperingKnickers Alright, thanks! Uhm, @MarcoTexture could you explain how you got to that high number of winds with this specific wire & hight?

I am so sorry for my late response and even more sorry for providing wrong info. I was wrong when I said the length is 20 cm, it is 20 inches. I just measured it again. in fact its a bit less than 20, ~18 inches which translates to 50cm. and the wire I used was 36 AWG if i remember correctly, it was really thin.

I know how hard it is to wind a coil as it requires a lot of patience. so I'm really sorry If I messed up your plans.

[MarcoTexture]

 

https://dl2.pushbulletusercontent.com/8Mnvr6nzh7NAcPw3KgMnbxqvLtppxpi1/20170505_222658.jpg

Edited May 5, 2017 by MarcoTexture

[cameroncoats]

Magnet wire (enamelled wire) will have thinner insulation than the wire you've used which will help with fitting more turns in. I'd recommend switching particularly as it's much happier with high temperatures.

[Gomo]

On 05/05/2017 at 9:33 PM, MarcoTexture said:

I am so sorry for my late response and even more sorry for providing wrong info. I was wrong when I said the length is 20 cm, it is 20 inches. I just measured it again. in fact its a bit less than 20, ~18 inches which translates to 50cm. and the wire I used was 36 AWG if i remember correctly, it was really thin.

I know how hard it is to wind a coil as it requires a lot of patience. so I'm really sorry If I messed up your plans.

No worries, I'll get another wire / coil, or should I do multiple layers on the old one? Is that bad?

 

On 05/05/2017 at 11:22 PM, cameroncoats said:

Magnet wire (enamelled wire) will have thinner insulation than the wire you've used which will help with fitting more turns in. I'd recommend switching particularly as it's much happier with high temperatures.

Thanks for the tip, is this one good for the job?  http://www.ebay.de/itm/36AWG-ENAMELLED-COPPER-WINDING-WIRE-MAGNET-WIRE-COIL-WIRE-250G-/141523210679?hash=item20f370d1b7:g:R7IAAOSwc0FUoTBP

[cameroncoats]

32 minutes ago, Gomo said:

No worries, I'll get another wire / coil, or should I do multiple layers on the old one? Is that bad?

 

Thanks for the tip, is this one good for the job?  http://www.ebay.de/itm/36AWG-ENAMELLED-COPPER-WINDING-WIRE-MAGNET-WIRE-COIL-WIRE-250G-/141523210679?hash=item20f370d1b7:g:R7IAAOSwc0FUoTBP

36awg might be a little on the thin side; what current are you planning on running through it?

Table here gives you rough values of what current you can expect to run at - 95°C should be fine.

[MarcoTexture]

I also suggest getting a longer PVC pipe and a thicker wire than 36AWG, 28-30. @cameroncoats +1.