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Re: [TCML] Lacquer



if it just so happens that you have a container you can seal that will hold the coil and the mechanism to rotate it while the epoxy cures, and that it so happens that you have a vacuum pump, and you use grease with a low vapor point on the bearings of the motor, then you could get rid of the bubbles by drawing a vacuum - not a high vacuum - 20 to 25 inches would be fine

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From: "Phillip Slawinski" <pslawinski@xxxxxxxxx>
Sent: Thursday, April 08, 2010 10:18 AM
To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
Subject: Re: [TCML] Lacquer

Rob,

Well, it took me a lot of practice to get results like that (and believe it or not, I'm still not entirely satisfied with it). I use a plastic spreader to apply the epoxy. On the first few coils I did I tried using a foam brush (that's a BAD idea). I have a DC gear motor to spin the form. I have that hooked to a variable DC supply and I can adjust the speed down to about four RPM. It's important to apply the epoxy at a slightly higher speed than you
let it cure at.  This ensures minimal dripping.  After you ensure that the
epoxy is spread evenly over the form you can slow the speed down.  I use a
heat gun to remove small bubbles from the finish.  You have to experiment
with this, because if you heat up one spot too much it will bubble, or it
will become so runny that it drips off the form.  One more important note:
you should do this in a low or preferably no traffic room.  Be careful not
to move too quickly and stir up dust. If dust lands on the form during the
initial phase of curing it will make a dimple in the finish.

-Phillip Slawinski

On Thu, Apr 8, 2010 at 10:43, Rob Byron <mustang_5l87@xxxxxxxxxxx> wrote:

Phillip,
How do you get your epoxy so crystal clear? I use a two-part epoxy ( not
cheap stuff) and it allways ends up foggy looking because of microsopic
bubbles. I use a 24h cure and have it set up on a rotating assembly with a
microwave turntable motor. Is it how you mix it that matters? Or how you
apply it?  Your coils look amazing by the way!

Rob.

________________________

On 2010-04-08 09:33:32 -0600 Phillip Slawinski <pslawinski@xxxxxxxxx>
wrote:

>
> Hi All,
>
> I too use the two-part epoxy coating on all my coils.  I built a coil
from
> the ground up to produce a long spark length compared to the secondary
> length.  It has taken a lot of work, but I think the results were worth
it.
> http://www.flickr.com/photos/pslawinski/4354745760/  During the process
of
> developing this coil I have had multiple flash overs.
> http://www.flickr.com/photos/pslawinski/4309814799/  I haven't lost a
> secondary to a flash over or spark related event. My secondary is > wound > with 34 AWG on a 12" x 3.5" form. Not coating a form with such fine > wire
is
> simply not an option. The wire is very fragile, and will break with > only
a
> mild amount of force, also with wire this fine expansion and > contraction
of
> the form due to temperature change will cause the windings to loosen up
and
> fall down.  Sadly, I know this from experience.
>
> -Phillip Slawinski
>
> On Thu, Apr 8, 2010 at 08:22, Peter Terren <pterren@xxxxxxxxxxxx> > wrote:
>
>> Firstly, the experiment with the conventional coil is not conclusive,
>> sorry.  Power was "about 20%" in the pre shot with racing sparks. No
>> mention
>> of actual values for the post shot and the sparks look very different >> on
>> the
>> pics.
>> I am not saying the result is wrong, but it is highly likely the
original
>> power level was not reproduced.
>>
>> Secondly, DRSSTC's are different beasts in terms of coupling. >> Obtaining >> better Watt's ratios (spark length/sec length) seems a lot easier. >> 13:4
=
>> 3.25 does not seem remarkably efficient in this regard.
>> On the other hand using an SGTC coil with no special insulation, I >> have >> Watt's ratios of 3.0 (96inches/32in). Others have claimed larger >> ratios
>> for
>> SGTC's but I have not seen clear photos to show this.  If you want to
>> follow
>> this link copy and paste it into your browser.
>> http://tesladownunder.com/tesla_coil_sparks.htm#6 inch coil (the best
>> ones)
>>
>> Nevertheless, the previous discussion of using ?Envirotex as a very
thick
>> layer does really seem to provide a lot of protection.
>> Some years ago I started a TC project to dramatically outperform this
3.0
>> Watts number. A lot of special fabrication was done and I still have
>> everything ready to start some final plans and construction. One day
when I
>> have a few moments........
>>
>> Peter
>>
>>
>>
>>
>> On 8/04/2010 1:16 PM, Dr.Hankenstein wrote:
>>
>>> Greetings,
>>>
>>> If you're not too sure on the effects of a good coating (or two or
>>> three) of varnish; please refer to a scientific evaluation on the
>>> following link:
>>>
>>> http://www.audiotesla.org/corona%20experiment.htm
>>>
>>> This should remove all doubt that varnish does more than just hold >>> the
>>> winding in place and end the hypothetical armchair speculation. Dr.
>>> Spark has at least 80 coats of varnish on "Fatboy"---13+ footers out >>> of
>>> a 4 foot secondary proves it:
http://www.drspark.org/fatboy1_rebuild.htm
>>>
>>> Regards,
>>> Hank
>>>
>>>   _______________________________________________
>> Tesla mailing list
>> Tesla@xxxxxxxxxx
>> http://www.pupman.com/mailman/listinfo/tesla
>>
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
>

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