RE: DC Tesla Coil - was rotary spark gap

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Malcolm Watts" <m.j.watts@xxxxxxxxxxxx>

Hi Gary,

On 29 Nov 2004, at 11:38, Tesla list wrote:

> Original poster: "Lau, Gary" <gary.lau@xxxxxx>
>
> Hi Dave:
>
> Winding a primary out of 24 gauge wire sounds like a bit too thin?
> Granted, you won't get excessive heating with only a 75 Watt power
> supply, but primary losses will still be significant.
>
> I also use a two-layer (copper tubing) primary, but with a fixed
> geometry and conventional tapping for adjustment.  See
> http://www.laushaus.com/tesla/primary.htm.  The two-layer construction
> is a great way to achieve a high inductance without an excessively
> large diameter primary.

FWIW, I use an acrylic sheet between each layer in my stacked
primaries some of which have a hole cut in the sheet to accomodate
the secondary. It wasn't clear from your pictures whether you were
using one or not. I mention it because you spoke of arcing between
the outer turns and the sheet can extend way beyond that. It also
allows the layers to be positioned even closer for highest inductance.

Malcolm