capnjonny 

I have a Pinarello Montello with a completely chromed frame . I stripped off the old paint and plan on repainting it.
I plan to use Eastwood 2 part Epoxy primer.

What research I have done recommends sanding the chrome with 320 grit before painting. Pinarello did not do this when they painted it originally . The chrome is good enough I contemplated building it up without any paint at all.
Should I sand the painted parts or leave it as is and just clean the metal before priming?
I don't want to screw this up

verktyg 

Most paints don't adhere well to the smooth surface of chrome plating. Depends on the primer. One of the methods recommended in days past was to lightly sand blast the chromed areas to be painted with very fine grit material. Ideally this will provide a matt finish with some surface "tooth" for the paint to stick to.

Downsides: All non painted areas need to be carefully masked... and if you ever want to have an all chrome frame you're out of luck.

If you are going to manually sand the chrome, masking is still important. Also, I'd recommend a finer grit - 600, 800 or even 1000 grit "wet or dry" Silicon Carbide sand paper. The scratch marks will be much finer and there is less likelihood of going through the VERY thin chrome plating. Silicon Carbide is harder than Aluminum Oxide grit plus the particles are sharper and work better for hard surfaces.

verktyg

Andy_K 

I'm just going to leave this here without further comment.

bwilli88 

Good primer, wait 24hr, good paint

Chuck M 

If you were truly up to leaving that anywhere, I'm sure many people wouldn't mind you leaving it in their garage or workshop.

randyjawa 

I have painted all chrome frame sets knowing full well that the paint will NOT adhere all that well. I would never sand the chrome finish on a frame since I do not like altering a frame set in any way, other than to paint and apply new art. I always want to prevent doing something that cannot be, easily, undone. Redoing a sanded chrome finish cannot easily be undone. So...

When I paint an all chrome frame set, I make darn sure that the chrome surface is impeccably clean by cleaning off all debris and then washing with a alcohol or lacquer thinner. With that done, I apply a good quality primer followed by my color coat of choice. If I apply stickers, that's all but if I apply water decals, I finish up with coats of clear coat.

All that said, I go out of my way to be gentle with the paint over chrome finish. I know that it will chip and or scratch very easily and I do not want that to happen. So, if you want to do what I do be sure to exercise great care in protecting your finished result.

As you can see this old Torpado was al all chrome frame set but covered, in most areas, with a translucent blue paint. Even this original finish was fragile.

Before my build (easy to see where the paint has rubbed off)...


After my build (I was very careful to preserve the original stickers since I was not planning on painting the frame set....

m.c. 

I always liked the cromovelato paint that's done over chrome.

bwilli88 

I would suggest that you not sand the frame as it breaks or scratches the chrome and that removes some of the protection chrome provides. Like Randy said clean the area to paint while wearing rubber gloves. Then good primer and paint. In the case of a chrome frame, the chrome provides rust and corrosion protection, paint makes it pretty. I did this to my Centurion I posted above as someone had stripped the seat tube chrome to put bottle bosses on. I also wanted some contrast for the logo so I painted the head and down tubes.

sced

I wanted to paint lug linings and lug windows on my Macario and did a search on getting paint to adhere to chrome. I found a recommendation for Elmers Probond Advanced and used it to good effect as a base coat over which I used Testors for the windows and a fine-tipped paint pen for the linings. I cleaned the areas to be painted with alcohol, applied the Probond to the windows a lug edges with a fine-tipped brush, and then the paints. The Probond is thin enough to be easily applied with a brush, it drys clear and the still-wet brush cleaned up easily with water. I applied Probond as a protective top coat as well.

To paint a frame one might apply a Probond base coat with a foam brush to minimize streaking. Without knowing how to remove dried Probond, some experimentation on a practice part is probably a good idea.

https://www.amazon.com/Elmers-E7502-.../dp/B00ARDVU4K

kunsunoke 

You could try this: Eastwood Bulldog

sloar 

Use a good etching primer followed by regular primer. The etching primer makes adhesion to the metal better.

merziac

Very thorough scrub and complete dry, then another thorough wash and complete dry with acetone or lacquer thinner and immediately apply the etching primer.

Used to be hot tanking was a way to go but some were too hot or dirty/toxic.