# Most efficient wire gauge for induction coils

1. Dec 14, 2008

### Cspeed

I am trying to find out which combination of wire loop diameter and thickness produces the most current. The problem with thin wire is obviously that it has a lot of internal resistance, but it is easier to wind in more loops. Does anyone know for a fact if a certain gauge/thickness is the best, or does it severely depend on the experiment's setup?

2. Dec 14, 2008

### Staff: Mentor

Last edited by a moderator: Apr 24, 2017
3. Dec 14, 2008

### Cspeed

Thanks for the response. I'm not sure about that calculator - I'll admit that I don't know a lot about this subject, and permeability especially. I know that wikipedia has a table of resistance per unit length for copper wire. I guess I'm just not sure how I would mathematically find which gauge is best, except through experimentation (and I don't own every gauge).

I'm sure that using wire that is .1 m thick wouldn't be very efficient, because few turns could get in. Other the other side, something that is .0000000001 m thick would be so thin that the resistance would probably be terrible. From anyone's experience, would it be better to use something like AWG 24, or 28, or 30, or 40 etc.?

4. Nov 2, 2011

### Forrestanfo

I am currently winding a 6 Inch Minimum, Ruhmkorff Coil. I have a core 18"x1-1/2" I.D. I will wind 17 " of number 12, 2 layers, 250 Turns total. I will have the ability to run with the 250 turns, or 175, in parallel. The outside diameter of the insulated primary will be 2-1/2", so my "Pies"-"Yo-Yo's" will be 6.25", I will probably go to 6.5". So the Sides of the "pies" will be 7"-7-1/2". The Secondary will be 8.75", which is really .75 over specification, however, My inner and outer insulation will be "bullet proof". Also a good coil, should be able to be disassembled. Don't try and max out your spark, it WILL lead to a Failure. If your building a 6" Coil, Don't go over 7". Size 34 wire is good, 36, cannot alway handle the pressure, and it is MUCH harder to work with. Is it that important to have a smaller coil, give a bigger spark? If your in some kind of competition, go for #38 or #40. Have FUN!! I could go on with specs, any questions please ask.