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Killa-X

Wed May 27 2009, 04:35AM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Right now, as my first wounded coil with what I had, I made a 1x6 inch tesla coil with maybe 34awg magnet wire. The primary was done on a 1.5" PVC pipe, 12 layers of extension cord wire. As you can guess, not much results. I was told to try Capillary tubing, and make a flat coil (by Arcstarter). What do you guys think? I might have seen 4mm copper tubing at gemmens, but it didn't seem long. Maybe they have Capillary in another area, like bathroom. I'll look soon as I can if that's the best case.

* would home depot have some?

* is this the best way to go for a mini SGTC? I don't fully understand why I can't flat coil 16 awg magnet wire...

Any other ideas please tell me! I'm on my way to sleep typing this on my iPod, so I won reply until tomorrow evening. But I'll check replys in the mornig!

Arcstarter

Wed May 27 2009, 06:14AM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

Well, capillary tubing is just really really small copper tubing. I never explain very good over MSN.

Those will work. I chose copper tubing, as i said on MSN, for three reasons. It is usually thick enough to withstand many times the current you are running (minus heating from resistive losses), it has plenty of thermal mass so it can dissipate plenty of heat, and the main reason is because of the skin effect. Google it if you need.

The top of the primary should usually (for a sgtc) be around lever with the bottom turn of the secondary. Change this to get longest sparks with not racing sparks along the secondary, and to make certain you do not get secondary to primary arcs.

The spacing (also said on MSN) can be pretty small, between each primary turn. Try something like .15 to .25 inches or so. The closer the better, as long as you don't get arcs along it. The closer the turns are to the secondary, the more energy will be 'picked up' from the primary=better and more efficient output.

The spacing from primary inner turns to secondary can be something like half an inch or less, i would guess. Just what ever works best. Remember, copper is very easy to bend, so you can bend as needed with ease. As long as you do not bend too much and break it, in which case you would need to solder it somehow.

I will make some of the capacitors tomorrow and send them to you tomorrow or the next day. Ill try to make them last for quite awhile. You are using DC input, so that is always good. They will still see HF AC, but this does not seem to be as hard on them as 50/60hz AC input. That makes no sense, but oh well. We will see.

Oh, i will also include some tiny 1 or so inch lengths of different gauge wire, and you tell me which matches your secondary wire best so we can find the actual gauge. If the wire was from the windings of a transformer like what i have, 36 gauge would be a very accurate guess. Just seems thicker than that to me for some reason.

And please, get some new mosfets XD.

1 dollar, 400v 16 amp.
Those will work just fine for the flyback driver, and they would work for a small sstc too.

Mads Barnkob

Wed May 27 2009, 02:20PM

Registered Member #1403 Joined: Tue Mar 18 2008, 06:05PM
Location: Denmark, Odense C
Posts: 1968

For two of my tesla coils I have used 12AWG, stranded and solid, both works fine at 300-600kHz without the primary heating.

Optimizing the primary with "expensive" coppertubing should only be done if the rest of the system is also optimized, no need to invest in great materials for some parts if you still have bottlenecks lowering performance elsewhere on the tesla coil.

sgtc:

vttc:

I use these 500V 20A IRFP460, got these mosfets at 1.1$ a piece, just make an offer lower than buy now:

They can take a great deal of punishment, I have used them in my fullbridge sstc that have pushed 2-4kw in CW mode.

Killa-X

Wed May 27 2009, 11:09PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Ya. I live in America, that's going to be fun with shipping...

Our store has only 1/8" as their lowest copper tubing. It would be best for me to buy at the store rather than ebay, because my brother who buys my stuff, is moving, and wont have a bank account for a long time. Plus I have to talk it over with parents. As with the store, I can most likely get it tomorrow if I wanted to.

1/8 inch seemed prity small to me, I think my alum. foil coil I made was about the same thickness really. I understand fully if I don't get the best results out of this. It's small, and bad quality. I got the magnet wire from a E-Core 120V 12V 2A transformer. It was my first coil I wound with crappy wire, so I have flat areas, and lifted areas. I plan when I get wire for a larger coil, to take time and take it serious now that I know what it's all about.

Mads Barnkob

Thu May 28 2009, 03:11PM

Registered Member #1403 Joined: Tue Mar 18 2008, 06:05PM
Location: Denmark, Odense C
Posts: 1968

Killa-X wrote ...

Ya. I live in America, that's going to be fun with shipping...

Flatrate shipping, ended at 10.5$ for shipping 38 fets, some diodes and sockets to denmark, its the same shipping price if I ordered from a company in denmark! outragerous shipping prices here :)

HV Enthusiast

Thu May 28 2009, 05:32PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Killa-X wrote ...

Right now, as my first wounded coil with what I had, I made a 1x6 inch tesla coil with maybe 34awg magnet wire. The primary was done on a 1.5" PVC pipe, 12 layers of extension cord wire. As you can guess, not much results. I was told to try Capillary tubing, and make a flat coil (by Arcstarter). What do you guys think? I might have seen 4mm copper tubing at gemmens, but it didn't seem long. Maybe they have Capillary in another area, like bathroom. I'll look soon as I can if that's the best case.

* would home depot have some?

* is this the best way to go for a mini SGTC? I don't fully understand why I can't flat coil 16 awg magnet wire...

Any other ideas please tell me! I'm on my way to sleep typing this on my iPod, so I won reply until tomorrow evening. But I'll check replys in the mornig!

The primary material isn't as important as the geometry (coupling) and configuration of the coil. If you're not getting the results you expected, its NOT because of the wire material. Its because of the configuration. Yes, thinner wire will certaintly heat up much much more than copper tubing, but its not going to make or break your performance.

The best way for a "mini" SGTC is simply to use 12 AWG solid wire. Heck, 16 AWG will probably work fine too.

I use 12 AWG wire even for my larger coils for initial tuning, and then swap it out later with copper tubing once i get the right tuning point. Dr. Resonance of Resonance Research also does the same thing with his coils.

Killa-X

Thu May 28 2009, 07:13PM

Registered Member #1643 Joined: Mon Aug 18 2008, 06:10PM
Location:
Posts: 1039

Well I know its due to the new power. Before when I was running only 12V 1A with 1 leyden jar, using a solid state sparkgap, I used extension cord as a primary wire, and did 12 layers. It resulted in 1inch streamer. With no ground near it. Later, I got a TON more power, and since I couldnt do stationary gaps, I had to use rotary. and my 12 coil (upward coil) extension cord isn't working good. I don't even get a true streamer.

So. Our place has some type of copper'ish tubing thats going either 30 or 50cents a foot. I want to sometime fix my coil to a FLAT coil.

I also, Need to install my 4ft high quality solid copper grounding rod. Michigans codes call for 10ft, and I was told by multiple people at the hardware store that 4ft would be greate. Our topsoil is very moist all year round and 4ft would easily get into very wet soil. the 10ft code is to assure theres more than 3ft of copper in solid water, from the water table, which isnt far down.

I'm sorry, I keep forgetting to change my camera settings. But that's the only clamps they had for the rods.. They are a hardware store based for house builders, not public majority.

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