[GreenKeys] ASR 33

[Seth Morabito]

* On Tue, Nov 26, 2013 at 04:31:11AM +0000, Jones, Douglas W <douglas-w-jones at uiowa.edu> wrote:
> What is the plastic used for the cover?  PVC?  ABS?  It's pretty filthy,
> and I wonder if mild soap is the strongest thing I should use, or
> is there something like Windex recommended.
[...]
> Bug 17 is a greater concern.  The window in the top of the cover is
> cracked and entirely loose.  It seems to be a different kind of plastic.
> Does anyone know what kind?  Repair or replace, that is the question.
> 

For cleaning mine, I used four tactics, all of which ended up working
very well:

1. Soap and water
2. "Simple Green" brand cleaner
3. Mr. Clean "Magic Eraser" (a very mild abrasive)
4. 000 synthetic steel wool to buff out surface scratches

The plastic appears to be some kind of ABS or acrylic. It responds very
well to acrylic solvents. I used both "Tenax-7R" brand and "IPS Weld-On
3" solvent adhesives to fix cracks. These solvents are VERY THIN and
watery, and will run everywhere, so you must be careful. Wherever they
run, they'll disolve the plastic and leave discoloration (or, rather,
they'll melt away the yellowing and leave the true original plastic
color behind). So go very carefully and slowly with a good applicator!

The clear plastic window is also acrylic, or at least it responds to
acrylic solvent. I used IPS Weld-On 3 to repair a very large crack in
mine.  Because the adhesive is so runny, it left a couple of ugly
deformed beads melted into the plastic, but I was able to remove them
with a lot of hand-sanding and buffing. The end result is nice!  You can
still tell there was a crack if you look closely, but it's much less
visible and the repair seems solid.

To re-attach the clear window to the cover, I used a non-solvent 
plastic cement (I'm sorry I don't remember which brand) and just kept
it clamped over-night. But first, I removed what was left of the heat
stakes and cleaned everything up so it would be flush.

>            Doug Jones
>            jones at cs.uiowa.edu

-Seth, NF6Q