Re: [hvlist] Really high voltage potting (Potting on the Cheap) (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Fri, 12 Sep 2003 17:48:59 -0500
From: jwhitmor@xxxxxxxxxxxx
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: [hvlist] Really high voltage potting (Potting on the Cheap)
    (fwd)



On 8 Sep 2003 at 6:42, High Voltage list wrote:

> Original poster: Steven Roys <sroys@xxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Sun, 07 Sep 2003 22:15:28 -0300
> From: Antonio Carlos M. de Queiroz <acmq@xxxxxxxxxxxxxxxx>
> To: High Voltage list <hvlist@xxxxxxxxxx>
> Subject: Really high voltage potting (Potting on the Cheap)
>
> Hi:
>
> I am searching for a good method of gluing a stack of two or three
> acrylic disks, to make an electrostatic machine with embedded sectors
> in the disks. Imagine a Wimshurst machine with the sectors inside the
> disks, accessed only through small buttons.
> I tried so far two methods:
> Gluing the disks with Araldite results in uncertain performance.
> Leakage is significant and water absorption is a big problem.
> Gluing the disks with hot glue works very well, but requires an
> oven, and the acrylic disks get a bit deformed by the procedure.
> I can mention that wax works too, but is weaker and can crack.
> I have two machines that ate now built with the hot glue method:
> http://www.coe.ufrj.br/~acmq/wommelsd.html
> http://www.coe.ufrj.br/~acmq/wehrsen.html
> I am now working in a larger machine, with disks that are too large to
> fit in my oven, and that anyway would probably deform excessively
> (I could adjust the border of the composite disk after assembling it,
> and find a way of mounting the contact buttons after the assembly too.)
> So, I am looking for an adequate glue that dries without contact with
> air, and becomes an insulator as good as acrylic. Some suggestion?
>
> Antonio Carlos M. de Queiroz
>
>
>
I use ethylene dichloride solvent and and thicken with plastic dust
from sawing plexiglas. The solvent can cause crazing when trapped.

I' ve seen your equipment (photos), and know that you require perfection,
which I believe will require a solvent free solution.

My best sugestion is to use the UV cure resin that is made for assembling
optics, or the consumer product used for repairing chips in car windshields.
You can get a tube of the windshield repair resin from most auto parts stores
for less than $10 to experiment with on scrap material. For more options,
please go to:

http://www.kemxert.com/prices/prices.html

They have a selection of various viscosity, UV cure resins.

Don't spend money on a UV lamp, (unless you want to), the sun is fine for this.