Misc - Glass Polishing
Added May 2007
How-to, Tutorial, Step-by-step, Technical Article
While the aftermarket has come a long way in recent years in providing parts for
classic muscle cars, there are still gaps in parts availability. Even one of the last
areas of frustration, namely door glass, has made great progress in the last few years.
New glass is available for most of the more popular models today.
But if the pieces you need are not available or you if want to keep your original date
coded glass, then you'll need to restore what you have so it will not look dull compared
to the new windshield you are going to have installed.
MCR uses professional glass polishing equipment for most jobs but we also use products
that you can get from the Eastwood Company. The pro polisher's main advantage is speed but
you can do an entire piece of glass with the Eastwood kit. It will just take more time and
patience. Here is how you do it.
There are two objectives you are going after. The first is to restore the
overall clarity and sparkle to the entire piece of glass and also to find and polish out
the scratches. With a black Sharpie or other suitable marker, place a line along the
entire length of each scratch on the backside of the glass. This makes it easy to find
your scratches and you won't polish off your marks once you begin.
For everywhere but the edges, an Autostock Scratch Removal system is used.
The main advantage of this machine is speed. It creates a vacuum that applies just the
right amount of pressure to the glass while a pump supplies a continuous supply of fresh
abrasive to the wheel. The circulating water based abrasive also keeps the pad from
overheating. The most important rule is to keep the machine moving. Stay too long in one
spot and optical distortion will be created in the glass. This process does remove glass
and is kind of like polishing a scratch out of paint. If you concentrate too hard and
long in one spot, you will leave a cup in the surface.
After an area has been worked for a while, the surface is squeegeed
off so that the progress of each scratch can be checked with a finger tip or fingernail.
Notice again how the marks under the glass make it easy to find all the problem areas.
While the Autostock works very well, its vacuum cup will not allow
the machine to reach the last inch or so near the edges. MCR uses Eastwood's Rhodite
Glass Polishing Compound and their Pro Glass Polishing Wheel to finish each job.
The process really couldn't be any simpler. Just sprinkle some of
the dry powder on the glass, wet it down, wet the wheel and begin polishing. Max speed is
2000 RPM. Use moderate pressure on the wheel and avoid using the edge. Yes, you'll
remove the scratches faster if you use the edge but you'll also end up with a wavy
surface. Remember to keep moving, keep everything wet and be patient. Expect to spend a
whole day per side depending on the number and depth of the scratches
Eastwood Rhodite Glass Polishing Compound (www.eastwoodco.com)