Painting Over Paint

[aka_locojoe]

Curious what eveyone does. Say you've got a frame with decent paint but you want to change the color. Assuming you don't strip the original paint off, what do you do? I sand the original coat to get rid of the sheen then primer and paint. I'm wondering if the primer is really needed?
Oh and I'm talking rattle can.

 

[xddorox]

Check out the CCM Galaxie build on the bikeoverhaul blog. That's exactly what I did. The original paint affords you the best protection and the primer gives it a nice even coat for the color coats. It works for me. :mrgreen:

 

[Clothespin n]

Check out the CCM Galaxie build on the bikeoverhaul blog. That's exactly what I did. The original paint affords you the best protection and the primer gives it a nice even coat for the color coats. It works for me. :mrgreen:

exactly......and the primer also builds up The Mil thickness,filling in voids and scratches as well.In this case it would be an intermediate coat...

If the origonal paint isn't failing( flaking,chipping,aligatoring )then a quick sand for "tooth and ancor" is perfect.If the origonal is failing you can work a bit more in those areas and "feather off" the sanding

But one thing I ALWAYS do before I sand is I wash/de-grease the substrate....THIS IS THE MOST IMPORTANT PART..not because the paint won't stick so much as ,when you sand before washing you are GRINDING/RUBBING/DRIVING all the contamanents into the old surface...
I then wash.....or whipe/dust.... again after I sand( before primer )

Sounds like overkill,but it beats watching a beautiful paint job shrivel up and fail...... :shock: :shock: :shock:

peace
Kev.

 

[xddorox]

The key to any paint job is prep, prep, prep and more prep. Saves a lot of trouble and contributes just as much to the quality of the end product. I'm all with you there Kev. Peace!

 

[Hooch]

oh and perfect for the wax removing befor the spray can paint job Duplicolor Prep Wipes availible at your local napa auto parts
http://www.caswellplating.com/vht/duplicolor_prepwipes.html

 

[Chicago Punk]

DOES THE SAME APPLY TO PAITING RIMS?

 

[sensor]

as long as theyre painted not chrome then its alittle different process

 

[Chicago Punk]

The rims I want to paint are aluminum.Should I sand them and primer? Thank's

 

[sensor]

yeah id sand them with 180 grit and then etch prime them(you could probably get away with just regular primer but if its raw metal better safe than sorry) then follow with a regular primer sand with 400 grit and shoot your color
its abit of work but theyll actually last if done right :wink:

 

[Chicago Punk]

Thank you for the info.What number grit do you recommend to sand the frame with? The paint on it is in very good condition.I just need to take the gloss off correct?

 

[sensor]

if youre going to prime it id use 220-320 grit if just color 400-500 grit

 

[stephen]

Primer helps the topcoats stick to metal and brands may have particles of zinc or other stuff to help stop rust. I don't use primer on top of a finish that's already there, i'm not saying that's the best way - just what I do

 

[Mr. Farrell]

advice please... i put on the first coat of color but missed some spots on top. should i touch those up before doing the second coat?

or can i g ahead and wet sand then touch them up when i put on the second coat?

thanx.