bobbyj

Hi,

I recently painted my bike flat black, but once i started riding it, i am noticing that the paint tends to chip really easy. I used 4 coats of duplicolor primer, 6 coats of duplicolor flat black, and 5 coats of valspar flat clear coat.

Did i do something wrong? I did sand the bike down to bare metal before i pained. What i intend on doing is just patch up the chips and apply a different type of clear coat. Any recommendation on flat clear coat brand/ advice?

Thanks

ScottNotBombs

RandyJawa owns mytenspeeds.com and has a good article on brush painting bikes. How long did you let the primer and paint dry for? A lot of people put their bike in the attic to help it dry more quickly. I've always waited a few days between primer and paint and at least a week between paint and clear and at least another week for the clear to dry, but that might be overkill.

wesmamyke

It's tough to do rattle can paint well. It's probably a couple things, like mentioned above rattle can paint takes forever to dry. Someone I know that paints motorcycles said if you can still smell paint at all it's not dry.

It's also hard to get the metal completely clean so the primer sticks well. Take a look at the chips, is it chipped to bare metal? Chipped through the clear and color but the primer is still intact? That will give you an idea of where you went wrong.

For what it's worth I think the right clear has A ton to do with it. The last frame I painted the fork got a different brand clear because I ran out after I finished the frame. Everything else was exactly the same, the frame chipped if you even looked at it funny, the fork looks factory and never chipped once.

ghostm42

I rattle-canned a bike with some success. After sanding it down, I primed it and gave it a day or two between each coat. Same with the paint and clear. I think it took about 2 or 3 weeks to apply all the layers of paint. It was during the summer and we were having a heat wave, so I let it bake in the heat. When I was done, I left it alone for at least two more weeks (moving it indoors if the weather looked bad) and finally road it at the end of summer.

Even giving it several weeks to dry, it was still more fragile than the original paint. I dropped my spoke wrench on it at one point and it made a small chip on the paint. After one year, it was still in very good condition, but I was always paranoid not to lean it against anything.

Now, I ride on a beat up frame and color in scratches with a sharpie. I'm much more happy not having to worry about the condition of the bike.

nhorton

I know this isn't in direct response to your "question" but for a fairly decent price (50-100 bucks) you can have it professionally powder coated and love the results.

Grand Bois

Rattle can paint can be very durable if you choose the right paint and do the proper preparation. This bike has a lot of miles on it since I painted it and no chips or scratches. Since the paint does not use a hardener, it needs a lot of time to fully cure. I left it alone for a month before I assembled it.

BCRider

Even the catylized automotive paint takes a couple of weeks to a month or more to fully reach it's final hardness.

Getting back to Bobbyj's paint job. I have to ask why so much paint and clear? Or did you dust on really light coats? I'd say it's either so thickly applied from so many coats that it's going to take literally months to fully dry and harden or that you may have applied it so lightly that it never really formed a proper film at any one coat. It all depends on how thickly you applied it. But it IS possible to apply stuff like this too lightly.

Part of the issue may be the 4 coats of primer. Primer is intended to be just that, a primer. You don't gain by using more than one coat. And if it's a high build primer intended to be sanded to fill in any minor scratches then it's a soft primer. And building up 4 coats of the stuff without sanding it back down means that you've got a really soft coating for the color and clear to sit on. Being soft may be why the black and clear is able to chip so easily now.

You've also got a switch in your product lineup going with the jump to the Valspar varnish. That may be creating a bonding problem with the Duplicolor black.

All in all I'd say doctor up the chips and leave it. Over time it'll likely harden up and become more ding resistant. If it doesn't then dumping on yet another coat or three of matt clear won't make it any better since it's likely the primer layer that is soft enough that it's not providing the proper support to the outer colour and clear layers.

Grand Bois

I used an etching primer and then white primer-surfacer (white brightens the red). There are four coats of color and four coats of clear.

If you can get access to a compressor and a detail gun, Hot Rod Flatz from TCP Global is the way to go if you want flat. It's 2 part urethane and very tough. No clearcoat is used with it. They sell quart kits. https://www.tcpglobal.com/kustomshop/ksflatz.aspx

This is Rally Yellow:



It's more of a satin finished after it's waxed:

fietsbob

a pint and some chips sounds pretty good this afternoon,