fish-eyed fuchs

[Teutonics]

I'm getting fish eyes when repainting! What am I doing wrong?

I sanded down the wheels for proper adhesion (bare metal in spots), wiped down multiple times with lacquer thinner, and sprayed with Wurth Satin Black Trim Paint (which is enamel, BTW). Temperature 60ish in the garage with low humidity. Spray a nice even coat.... then a couple minutes later I get fish eyes with bare metal spots showing! I've done this twice (removed paint, cleaned, and resprayed) and same results!

Suggestions?

[scottb]

Sounds like there's something embedded in the pores of the casting. Have you tried a sealer/primer first, before the Wurth?

[ipapilot]

Paint definitely doesn't like bare metal too often. I had the same experience on some bare metal spots in my interior. I would highly recommend primer, possibly the etching variety.

[targa80]

I would think etching the metal and a coat of primer is called for.

question for the board:

Isn't the fuch done with black anodizing and not black paint?

[89911]

I use a "paint prep" cleaner available at the auto store. Also doesn't hurt to use a quick drying black primer. You can sand out any imperfections prior to final paint.

[89911]

Originally posted by targa80
I would think etching the metal and a coat of primer is called for.

question for the board:

Isn't the fuch done with black anodizing and not black paint?

Black painted centers are done at the factory. The centers are anodized like the rims.

[Wil Ferch]

OEM Fuchs black is paint...not anodizing.

All the remaining silver color is anodized.

---Wil Ferch

[stomachmonkey]

Also make sure the paint is thouroughly mixed.

In addition to the previously mentioned reasons, paint that is not mixed well enough can leave fish eyes.

Shake the can till your arm is ready to fall off.

Scott

[greglepore]

I'm willing to bet its silicone, likely from tire dressing overspray. It gets deep into any finish, and will cause endless fisheye probs. Bodyshops won't allow any silicone product near the shop for this reason. No amount of thinner will help. You'll need a primer/sealer at a minimum, or strip the wheels.

[white87911]

Hey guys,
When painting any type of Aluminum I have learned that you really need to prime the surface first. You need to use a zinc chromate "etching primer", you can buy this at most local auto parts stores. (good ones, not Pep Boys) Also make sure the surface is clean, i.e. lacure thinner, but that sometimes has led to problems. There is also make a surface prep that removes silicone which works really well if not better. Then "AND HERE IS THE BIG SECRET TRICK" let your spray paint cans sit in a bath of HOT WATER for 10 minutes before spraying (shaking ocassionally) this helps the paint to flow smoothly and also allows the pressure to build up in the spay can so the paint is atomizes better. I have had great luck with this procedure even in painting plastic parts.
Cheers,
Erik

[toolman]

Do not use lacquer thinner to clean. Use a product like Dupont 3812 or an enamel reducer. The trick is to clean with one rag (with cleaner) and wipe off with another rag to pick up the contaminants. Thinner dries to quickly and leaves the dirt on the surface. You MUST use an etch primer on aluminum or the paint will just flake off.

[twin plugged targa]

Both greg and tool man are correct,
Silicone will repell paint causing fisheyes.
Also an etch primer is best advised when painting bare aluminum for best surface adhesion, this however will not help until you have solved the problem of contamination which IS your problem!

I may not have rebuilt any 911's yet but I have painted a **** load of aluminum yachts.

The other, more likely contaminant you should expect is OIL!!!!
Aluminum is very absorbant and once your metal has absorbed oil you will have one b1tch of a job getting it out, if in fact you can!.
Bare alminum should be protected from oil like the plague before repainting for this very reason.

I would use copious amounts of denatured alcohol in stages, waiting between efforts to allow the oil to work it's way to the surface.

If you are still having problems, go to your nearest yacht store which stocks the 'Awlgrip' (US paints) brand of paints. These have the best primers for bare metal which include acid wash treatment.

With these brands of paints they also have an 'anti fish eye' addative which you can add to their paint to overcome the problem.
What this does is actually add silicone to the paint!!!! Mad as it sounds - it works!.

I would put my money on oil as your culprit, and you will have to persivere to remove it.
Hope this helps and good luck!
Rgds Ben

[Gordo2]

No help on the fish eyes, but here's my story so you don't feel you are the only one who has had problems painting Fuch's:

I prep'd mine by hand sanding... Yep, about 3-5 hours each. I read that oil deposits on the wheels were a no-no (by the way, touching the surface with your fingers can leave oil deposits). Cleaned the wheels prior to spraying.

Coated with a primer made for Al. No problem, went on nicely. Sanded to around 220 after 2 coats of primer and cleaned again.

Sprayed them satin black (can't recall type of paint I used). Temp was around 65 deg and humid. The stuff didn't dry. Covered them with plastic for 4-5 days hoping they would dry. They still felt sticky .

Just to see if they were in fact sticky and not hardened I scratched each with a fingernail (about an inch long). Discusted that they didn't adhere, I put them on the car and that's where they are now. Meanwhile the surface dried over the next week or so and outside of the scratches that I put in them with the fingernail, look great.

Not looking forward to doing it again, but I will... sometime.

Chalk it up to learning experience.

Good luck,

Gordo

[geof33]

Yep, Gar-on-tee it's old Armour-all (silly-cone). Go to a pro paint shop and pick up some PPG pre paint prep. Cleans the metal to the bone. Then a good catalyst sealer should do it before final coat. Be sure to clean the sealer as well, before color. I agree with the let the can get warm thing, but you don't want the paint over about 75-80 degrees, causes other problems. Warming the can also helps the propelant stay more consistant... good luck

[speeder]

Lots of good advice here, I will just add that I have had success painting by cleaning really well w/ alcohol, then always a final rinse w/ H2O, preferably distilled or at least bottled, (Sparklets, Evian, etc.). This is what body shops do before they paint something, the water rinses off all dust and residual from the solvent, (dust will definitely cause problems), I spray things w/ a rattle can and get pro results using this technique. Good luck.

[Wavey]

I agree with Greg, too. Silicone is the work of the devil.

There's another solvent that's excellent for final paint prep. It's called Bestine and it's available at art supply stores. It is actually a thinner that was made for rubber cement (remember that?) and it REALLY leaves a clean surface. I always use it in the shop for a final wipe down. It evaporates very fast and doesn't leave any residue. I never have any fisheye problems when I use it. Kind of expensive, but when I find something that works I don't care what it costs.

[RickM]

The solvent I've always used for removing grease, oil or wax/silicone has been Dupont's Prepsol. It is step one of clean-up as laquer thinner or enamel reducer must be used to clean the Prepsol residue off.

[pohsche]

Try Simple Green cleaner. I will almost guarantee it works for you.

Alan Poh
'77 Carrera3.0

[greglepore]

Prepsol is excellent stuff, pricey, but it works . I've have a can of dupont fisheye eliminator which I'd be happy to send to you, but it doesn't help if you're shooting rattlecan paint.

[RickM]

Yes, Prepsol is a "wash" specifically made to address this issue. Last I bought a gallon i think it was around $20 at a Paint supply place. Not sure what the cost is now.