Do your own paint job and save a buck or two....
Under no circumstances should a "DA" sander be used on any plastic bike parts...you'll end up "flat-spotting" the plastic and then you'll be saying a lot of funny words. Instead of using a "DA" sander, just use 120 grit dry paper and hand-sand the plastic. Don't go ape-sh*t with pressure when dry sanding plastic...you'll just make deeper scratches that need to be removed with the wet-sanding process. You should only need to use the 120 dry paper if there are deep scratches already present on the plastic. I wrote this for a friend that wanted to know how to paint a fender...so just substitute your part of choice wherever you see the word "fender". The process is exactly the same. The only differnece between "then and now" is that I graduated to a full-blown paint booth in my basement compared to the "spray cans on the back porch" system that I used when I painted my Seca black. Pics of my recent work are available upon request...just remember, different cameras make for different resolution and picture quality! My ex-wife snaked my digital camera when I gave her the boot...fair trade if you ask me! ;0)
Here goes...
The way I did my fender was using an "old-school" bodyshop technique...lots of elbow grease and progressive grades of sandpaper. I started out by taking a dual-action sander with 80 grit and sanding the major scratches and shine off of the chrome. After that I used the DA again, but with 120 grit for the same purpose. The next few steps are the "fun" ones...you tend to get a little dirty. Take some 220 grit wet sandpaper (all wet paper is black in color), have a bucket of clean water nearby, and soak the paper for a few minutes in the bucket. You want to work in long even strokes, going the length of the fender, and start to "buff" the swirl marks left by the DA sander. Keep the paper clean and soaked, occasionally dousing
the fender to clean any residue...this keeps the paper from "loading" with old finish. When the majority of the swirl marks are "smoothed" over (no rough or defining edges) go to the next grit, which would be 400. Use the same technique until the scratches disappear a little more. After the 400 grit, you'll want to go to 600 or 800 grit and buff any remaining roughness
out of the fender. I took it one more step and went down to 1200 grit...it's not totally necessary, but it really makes the painting go a lot easier.
When you think the fender is sufficiently buffed, dry it with a lint-free cloth (or paper towel) and let it dry completely. The next steps are pretty simple, but it makes a world of difference between a crummy job and what you saw on my bike. Just to fill you in on a little secret, I did all the spraying with $2.99 spray cans...it's all a matter of proper application and
drying between coats. Spray the fender with an ultra-thin coat of primer and let it dry completely. Then spray another slightly heavier coat over the first coat and allow it to dry. When it's completely dry, wet sand it with 400 grit paper. When sanding primer, remember not to use a lot of pressure...all that you want to do is smooth out the primer, not remove it.
Apply enough coats to cover the fender and work your way down through the same grit sandpaper you used initially. Just be sure to allow each coat to dry and try NOT to get any finger prints on it as well...the oils in your hands will show up in the paint. Basically use the same technique to lay down the paint as you did the primer, wet sanding LIGHTLY between coats.
When the last layer of paint is dry (DON'T wet sand the last coat), use a high quality clear high gloss lacquer and spray it the same way you did the primer and color coat...again LIGHTLY sand each coat before laying down the next coat. Let the final (unsanded) coat dry AT LEAST 24 hours...more is better...and then put it back on the bike. Wait for a couple
weeks before waxing it since the wax will actually scratch the finish. It seems like a drawn-out process (and it is!), but this will leave a finish so high gloss it will look like you can reach "into" the fender. Give it a whirl on something and you'll see what I mean!
Sorry the painting process got a little "wordy" but there's no way to briefly describe the process. My step-father taught me all I know about bodywork in his shop over a span of 12 years...and he was in business for almost 60 years!
Martin H. Rohrbach
Drytown Club Works, Inc.
deadhead@ptd.net