Bicycle Mechanics - Painting steel frame--how much to sand/file down

hi there

im painting my first frame tomorrow-a beater steel schwinn approved...

the guy at home depot recommended grade 1 or 2 steel wool instead of sandpaper

my question is how much should i wool down the frame before applying primer? he said it wasnt necessary to completely remove the old paint.. but i didnt ask on specifics on how fine to wool... strip 50% of the paint? 25%?

Leave the orignal priomer on, if you can. Its usually a light colour.
I stripped it off, and applied my own. Good enough, but not as effective as factory primer.
Dont expect a paint-shop finish. Home painting is strictly utilitarian.

Before u start that u need to clean and wash the bike thoroughly in preparation to painting (frame with no components please). After it has dried you need to wipe it with a wax remover such as "prepsol" or similar to remove grease film and maybe wax and bitumen. This is so that when you use the steel wool you dont create a fine slurry of paint and wax mix that MIGHT penetrate the surface which is now porous.

You need to rid the entire frame of any "GLOSS" finish if thats the finish to begin with. Make sure that all crevices are removed of any "GLOSS" so that when dry it kooks like a "MATT" surface all over. This gives you the datum to refer to that you have done the job well for primer coat. Remember not to handle the frame with bare hands because your hands are notorious for body oil to get on the surface. If you have any imperfections which im sure it might have u need to fill these and sand using WET AND DRY paper and sand out feathering smooth as silk.

I hope there is no steel showing through anyway because this will require further treatment with "PHOSPHORIC" acid metal conditioner. (always read all instructions for any product.) Hopefully you dont have metal showing through at the start of your exercise.

Once satisfied use prepsol again never forgetting to touch the frame. eg (use gloves).

2 pack primer is more resiliant as is top coat 2 pack for a hard surface but this may need baking in a oven (Industrial not kitchen LOL). In short terms you need only to remove the "gloss" which should indicate the amount to be removed.

Please talk to your local paintshop or visit a library on automotive finishing plce in your area. This will give you a "World of information". Good luck with your new creation hopefully you could show it of here in the forum,,,it will be your handywork and if done well then you've mastered a new art.


thanks for the very detailed and thorough tips! this is still for a beater project bike...and this painting exercise is actually just practice for when i paint my real workhorse (87 trek)

if there are exposed metal/rust areas on the frame... what should be done? sand off the rusted area?

thanks for the very detailed and thorough tips! this is still for a beater project bike...and this painting exercise is actually just practice for when i paint my real workhorse (87 trek)

if there are exposed metal/rust areas on the frame... what should be done? sand off the rusted area?
I did my 73 Schwinn Speedster, and stripped to bare metal using aerosol paint stripper. Take this opportunity to silver-solder some lugs onto the frame!

http://www.geocities.com/thespeakerguy/speedster3.html

check out the prices of your local powder coating workshops, it might be a little bit more than the paint & sandpaper but no mess to clean up. Paint and sandpaper will cost for me AUD$25-30, powder coating does professionally cost $55. I have paint stripped and sand 2 frames, it takes me about 4-6 hours to prepare a frame. My 2 cents is to take it to a powder coating shop and use the time to ride.

hi there

im painting my first frame tomorrow-a beater steel schwinn approved...

the guy at home depot recommended grade 1 or 2 steel wool instead of sandpaper

my question is how much should i wool down the frame before applying primer? he said it wasnt necessary to completely remove the old paint.. but i didnt ask on specifics on how fine to wool... strip 50% of the paint? 25%?

How good of a job do you want?

Technique helps, but a repaint job will never be any better than your surface preperation and won't any better than the materials that you use. Unless part of your goal is the satisfaction of doing it yourself, local powder coat finishers have gotten so cheap that it's hardly worth while to mess with a rattle can paint job anymore.

hi there

im painting my first frame tomorrow-a beater steel schwinn approved...

the guy at home depot recommended grade 1 or 2 steel wool instead of sandpaper

my question is how much should i wool down the frame before applying primer? he said it wasnt necessary to completely remove the old paint.. but i didnt ask on specifics on how fine to wool... strip 50% of the paint? 25%?

Hey there...

I tried ONCE to repaint my steel frame. I did get the look that I was going for, but durability was not there. For all the time and effort you will be investing... it may well be worth it to have it professionally powder coated. I was able to have mine sandblasted, primed and get a two-tone (dark blue to purple) blend for about $100. The finish is perfect and has held up for 3 years so far. You can also check out some of the auto painting shops. Good luck!!!