Subject: Time:11:38 AM
OFFICE MEMO MGA Udate, or MY BONDO WEEKEND Date:8/26/91
Well, I spent the weekend ladling glop onto my car, and I have a few
observations. Knowing that they will be of no interest whatsoever to anyone on
the list, I none the less insist on boring you with them....
Maintenance of a good work rhythm seems to be vital to success at dealing
with bondo. From the moment the catalyst touches the resin, you're on a
schedule. So I found it helpful to get my ducks all in a row first. Walk
around the car, find the low spots, circle them with a magic marker. Get the
sanding blocks loaded with fresh 80 grit. Mix up a fist-sized chunk of bondo.
Walk around the car, and slather it onto all the low spots. Use a long,
flexible straight-edge to draw the bondo down in thin sheets over the low-crown
areas; use the little plastic spreader on the high-crown spots. Got it all
spread? Quick, back to the workbench; clean the bondo off all the tools.
Get'em squeaky clean by 1) Use each tool to scrape the rubbery bondo off the
other tool, thus acheiving STAGE I cleanliness. 2) Use a razor blade to
scrape the tools almost clean. 3) Use paper towels dipped in lacquer thinner
to acheive STAGE III, with no visible glop left on any tool. All clean? Back
to the car. The filler has now set to the consistancy of hard rubber. Some
concerted rubbing with that eighty-grit sanding block gets the bulk of the high
spots down. I found that the best block was a flexible plastic one that takes
a strip of paper cut the long way. This block could be bent to conform to the
high-crown areas, and yet could lay flat over the low-crown ones. After a
while, though, I appreciated the convenience of my air-powered jitterbug
sander. Loaded with 80-grit, that thing went through fresh bondo like a power
mower through tall weeds.
Okay, bondo's dry. Still got low spots? Here we go round the car again
with the magic marker....
Another topic of disinterest would be prepping the metal, particularly the
aluminum. I got a pair of aluminum-treating chemicals, "Alumiprep", and
"Alodyne". The alumiprep has soap and acid in it. You brush it onto the
aluminum, it fizzles and sizzles a bit, then you hose it off. Aluminum clean?
Well, maybe. Dirty aluminum looks much like clean aluminum. Enter the
"Alodyne"ing solution. You brush this on the aluminum, and it reacts with it,
"passivating" its surface. More to the point, the aluminum turns piss-yellow.
But only the clean part. The parts you didn't clean well enough stay aluminum
color. After four or five cycles, and some inspired sanding, my aluminum hood
and trunk lid turned a uniform yellow, and I knew it was really clean.
See, I only want to do this job once.
- Jerry ( exhausted, with bondo-covered fingertips )
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