[R-390] Front panel paint removal

[rbethman]

On 8/3/2011 1:00 PM, Tisha Hayes wrote:
> --------------------------------------------
> Oh, I know the feelings. Back when I was a "lab rat" at college there were a
> few times it was "up to the elbows" in PCB oil on the load banks. Nice
> toasty, 140 degree transformer oil. I tried to find the big black rubber
> gloves but more times than not, they had more oil in them than the load bank
> had in the tank. I would always scrub down with soap and water after dealing
> with the load banks but some of the other "rat-ettes" were perfectly happy
> to just wipe their arms down with scrap cloth towels.
>
> In the 90's I had a super-acute exposure to benzine (industrial accident)
> that overwhelmed my full face respirator in a matter of seconds. I was the
> "industrial hygiene lab rat" that time and was doing a Draeger glass tube
> pump sample to determine the benzine levels. It was supposed to be 10 pumps
> through the tube and then read where the brown line was on the side of the
> tube. I was still halfway through the first draw on the pump when the tube
> turned totally brown (saturated) and I could taste the benzine in the air as
> the organic solvent breathing canister filter was swamped. Just taking the
> 20 steps or so out of that area were nearly impossible. I almost passed out
> from the benzine fumes. I figure that one incident probably took a year off
> of my liver. At least I do not drink alcohol or do other obnoxious, ilicit
> things to my chemistry with drugs.
>
> I bake the paint on my radio panels in my kitchen convection oven (Jennair)
> that has convection air circulation inside and an external exhaust fan that
> goes by duct to outside of the house. Fortunately it does not take long to
> bake a radio panel and I only do that work when it is cool enough for me to
> have all of the windows open. After baking I shut down the convection mode
> and leave the exhaust fan on the oven running for a few hours. The panel
> comes right out of the oven and I put it on top of the porch railing outside
> for another day.
>
> I would never try that with a gas fired oven (only have electricity up here,
> no gas) nor would I do that with something that did not have an external
> ventilation system.
>
> Baking the enamel paint really makes a difference in how the panel turns
> out.. I am in the process of making every radio panel the exact same color
> as I have a case of the same color paint.
>
> I have not had to do anything really aggressive to remove old paint. I use
> Strip-Ez and let it sit for a few hours before going after it with a plastic
> scraper. I have also used lacquer thinner and some automotive paint remover/
> thinners. Usually I can clean out the lettering with a small brass brush or
> even a hard toothbrush.
>
I only have electricity here - no natural gas. A 1979 "experiment" in 
total electric homes.  So I don't have the issue of the volatiles in the 
oven.

My "breathable" air source was fed by air line from compressor and 
breathable air filter immediately after.  This was late '70s. PCB 
exposure was necessary to change voltage taps in the main step down 
transformer with switchgear. Generator was one trailer, feeding the xfmr 
and switchgear trailer mounted. One instance was feeding the NOAA Ship 
Researcher. Second instance was emergency standby for DC VA Hospital 
while engine was being overhauled.  I was fortunate in that we didn't 
rely on a filter mask!

Bob - N0DGN