[SEL] Low tension coils

[Dave Croft]

----- Original Message ----- 
From: "Elden DuRand" <edurand at iglou.com>
To: "The SEL email discussion list" <sel at lists.stationary-engine.com>
Sent: Friday, November 17, 2006 11:31 PM
Subject: RE: [SEL] Low tension coils


> Ron & Steve:
>
> I think I didn't give enough information before.  Referring to my 1908 Electrical Engineer's Handbook, I have the following data 
> for annealed copper wire:
>
> 16 gauge wire - 249.4 ft/Ohm
> 18 gauge wire - 156.9 ft/Ohm
> 20 gauge wire - 98.66 ft/Ohm
> 22 gauge wire - 62.05 ft/Ohm
>
> For a 6 Volt coil to draw 2 Amps, you'd need 3 Ohms or:
>
> 16 gauge wire - 750 ft
> 18 gauge wire - 471 ft
> 20 gauge wire - 297 ft
> 22 gauge wire - 189 ft
>
> For a 12 Volt coil to draw 2 Amps, you'd need 6 Ohms or:
>
> 16 gauge wire - 1,500 ft
> 18 gauge wire -    942 ft
> 20 gauge wire -    594 ft
> 22 gauge wire -    378 ft
>
> Simple, eh?  Makes me want to go out and wind a few coils!
>
> Other than measuring the length of the wire before starting winding, you could select your wire gauge and make a guess at the size 
> of bobbin you'd need for the requisite amount of wire (adding some just for yucks).  Then, after winding what you -think- is 
> enough, hook one lead of your trusty Ohmmeter to the "starting" end then scrape just a minute amound of insulation off the wire 
> and measure.  From that, you should be able to tell how close you are.
>
> To fix the insulation, you could either fold a tiny sliver of tissue paper around the wire then wind it onto the winding or you 
> could give it a shot of either lacquer or "glyptol" to insulate the spot.
>
> Take care - Elden
> edurand at iglou.com
> http://www.oldengine.org/members/durand

Hi Eldon, you don't give the supply voltage so
I cannot check out your currents.
Dave Croft
Warrington
http://oldengine.org/members/croft/homepage
http://community.webshots.com/user/crftdv