From: Bert Hickman[SMTP:bert.hickman-at-aquila-dot-com]
Reply To: bert.hickman-at-aquila-dot-com
Sent: Sunday, January 11, 1998 2:30 AM
To: Tesla List
Subject: Re: ACRYLIC?
Tesla List wrote:
> From: Zuma[SMTP:mwise-at-ns.sosis-dot-com]
> Reply To: mwise-at-ns.sosis-dot-com
> Sent: Saturday, January 10, 1998 11:40 PM
> To: tesla-at-pupman-dot-com
> Subject: ACRYLIC?
> Does anyone know the dielectric constant on Acrylic and its breakdown
> voltage per mil? The reason I ask is because I came across some at
> McCoys building supplies. It is about 25 dollars for a 4' by 8' sheet.
> I am considering using it to make a plate cap and submerging it into
> a custom plexiglass box filled with mineral oil.
In the final analysis there are few common dielectrics better for Tesla
Coil use than low density polyethylene (LDPE), high density polyethylene
(HDPE), or polypropylene (PP).
Acrylic is short for PMMA (Polymethyl Methacrylate), commonly known as
Plexiglas or Perspex. It's dielectric constant is in the range of 2.7 -
3.6 (frequency dependent, and decreasing at higher frequencies), and in
Tesla Coil service, will withstand about 150 Volts/mil. Unfortunately,
it's also quite lossy, having a loss tangent of between 22 and 50 x
10^-3. This is about 250 - 500 TIMES greater than LDPE, and will rob
your coil of power and performance. Use LDPE instead for best results...
it's also less expensive!
Safe cappin' to you!
-- Bert --