Neon sign transformers for Tesla coil

[DerStrom8]

I hope so, It said a lot about corona adding to the energy ineffectiveness due to heat on the caps (which makes since) still I hope this baby will put on a good show.

Corona can certainly be an issue. The best way to combat that is to submerge the plate cap in a vat of mineral oil. This will help prevent arc-over within the cap.

 

[gary350]

Well this site is a downer... I was already building my glass plate capacitor and I think I still will, but this site is truely against everything except for MMC and bottle caps.

Stefan's Tesla coil pages - cap page

I built several glass capacitors and though they were GREAT unit I built a good capacitor then I trashed my glass capacitors. Build good caps or buy some. MMC caps work good but people that use to have reasonable prices have increased their price to get RICH from us. Some of those people want $15 each of a cap you need about 20 of them = $300.

 

[billybob]

Corona can certainly be an issue. The best way to combat that is to submerge the plate cap in a vat of mineral oil. This will help prevent arc-over within the cap.

I don't know if that would be possible with the setup I have, but I:m adding a microwave fan to cool the plates a little a probably shave the edges of the aluminum sheets so its rounded and glue the edges to the glass. Do you think glue would be a good idea?

 

[DerStrom8]

I don't know if that would be possible with the setup I have, but I:m adding a microwave fan to cool the plates a little a probably shave the edges of the aluminum sheets so its rounded and glue the edges to the glass. Do you think glue would be a good idea?

Glue around the edges would probably be good, but do try to find a way to submerge it in oil. It'll definitely help.

 

[billybob]

Glue around the edges would probably be good, but do try to find a way to submerge it in oil. It'll definitely help.

AHHH more construction. I stink at that, but ok I'll try, do you think the plates in a wood casing be fine in oil or would it damage the wood?

 

[DerStrom8]

AHHH more construction. I stink at that, but ok I'll try, do you think the plates in a wood casing be fine in oil or would it damage the wood?

Great question, I'm not sure. I suppose it would depend on the type of wood and the type of oil. I don't imagine it would damage the wood though.

 

[shortbus=]

do you think the plates in a wood casing be fine in oil or would it damage the wood?

Wood for the most part is porous, with time the oil will saturate the wood and make a mess. You could though use a plastic container and make a wood surround to hid it. A container like this as an example any Walmart, Target, Dollar General type store will have them - https://www.target.com/p/rubbermaid...r/-/A-53696326?preselect=51097785#lnk=sametab

 

[shortbus=]

shave the edges of the aluminum sheets so its rounded and glue the edges to the glass.

Not sure, but are you planning to leave a certain amount of the glass plate exposed around the edges of the aluminum? Your aluminum sheet with a frame of glass around it?

 

[billybob]

Wood for the most part is porous, with time the oil will saturate the wood and make a mess. You could though use a plastic container and make a wood surround to hid it. A container like this as an example any Walmart, Target, Dollar General type store will have them - https://www.target.com/p/rubbermaid...r/-/A-53696326?preselect=51097785#lnk=sametab

I’m not sure what you mean here, are you talking about placing the wooden glass plates holder in a plastic container? Or not using wood at all?

 

[billybob]

Not sure, but are you planning to leave a certain amount of the glass plate exposed around the edges of the aluminum? Your aluminum sheet with a frame of glass around it?

Yes I plan to leave about a quarter to half inch space on all sides except the terminals of cours.

 

[shortbus=]

I’m not sure what you mean here, are you talking about placing the wooden glass plates holder in a plastic container? Or not using wood at all?

Ideally no wood at all. Wood is not something people use to normally contain liquids. Whiskey and wine barrels are some what of a container but also have a certain amount of leakage, called the "angels share". They are also put under much more compression by the bands than any joint you can make.

 

[shortbus=]

Yes I plan to leave about a quarter to half inch space on all sides except the terminals of cours.

I think you should read some more about glass plate caps, that doesn't, from memory, seem like near enough space.

 

[DerStrom8]

Did I misunderstand something? I thought the OP was asking about using a wooden frame to hold the plates together, and then I recommended submerging the entire thing in a vat of oil (probably a plastic container).

 

[billybob]

Did I misunderstand something? I thought the OP was asking about using a wooden frame to hold the plates together, and then I recommended submerging the entire thing in a vat of oil (probably a plastic container).

Yes that is what I was talking about. Here is a picture of the beginnings of the wooden case and I can buy a plastic container later.

 

[shortbus=]

Did I misunderstand something? I thought the OP was asking about using a wooden frame to hold the plates together, and then I recommended submerging the entire thing in a vat of oil (probably a plastic container).

Guess I'm the one missing something. I thought he was talking bout a wooden container to hold the oil. Because fo the chances of flashover starting a wood frame around the plates to burn or char. Charred wood is carbon and probably conductive at high voltages and frequencies.

 

[billybob]

Guess I'm the one missing something. I thought he was talking bout a wooden container to hold the oil. Because fo the chances of flashover starting a wood frame around the plates to burn or char. Charred wood is carbon and probably conductive at high voltages and frequencies.

Sorry for the confusion, Wooden casing in plastic tub is the objective.

 

[billybob]

Alright here is an update on the tesla coil. Made the variable vacuum spark gap, I have a question though, would it be better to suck air from the electrodes or blow air out them? Also I will be buying the top-load air-duck soon, I had one but turns out its a little small. Also I am currently working on the cap bank (easily the hardest part besides the secondary) the glass plate design, but once I get some money I think Im just gonna go ahead and purchase some MMC caps. Ill keep you posted about that since I don't really understand teslamap and what it is suggesting. Also Im a little conserned about my transformer idea with two OBITs and determined to in phase will only produce 10k at 46 mA. Might resort to MOT bank, I honestly don't know. This is an awesome project though and am thoroughly enjoying blowing my college fund on this sucker!!!

 

[DerStrom8]

I don't think there's much difference between a blower or a vacuum gap. As long as air is moving through it and keeping it cool, the direction is mostly irrelevant.

I strongly recommend JavaTC for designing coils. It's a great tool and is much easier to understand than TeslaMap (in my experience, anyway):

https://classictesla.com/home/javatc3d/

I do not recommend jumping to MOTs right away. They require not only just being careful (which I'm sure you would be), but lots of care to keep them from damaging one another. They are not designed for high voltages required for Tesla coils, so insulation becomes a concern. You would need to submerge them in oil as well, which gets very messy and heavy. They are more difficult to predict (output voltage, current, etc) so sizing them properly for your coil will take additional work. In lots of cases MOTs can be more trouble than they're worth.

 

[billybob]

I calculated the wattage to be around 1800 would this be powerful enough to drive a 4 inch by 25 inch secondary?

 

[DerStrom8]

I calculated the wattage to be around 1800 would this be powerful enough to drive a 4 inch by 25 inch secondary?

1800 seems a bit high. How did you come to that number?

500W is probably good for a coil with a 4x25 secondary.