# Wurth Silver Alloy Paint - Very Rough Finish



## neil.knapp (Sep 27, 2009)

Hello all,

I've been refurbing one of my alloys and got to the stage of painting it with some Wurth Silver Alloy Lacquer (paint).

It's a metallic paint and so has small flecks of metal in the paint. I painted the whole wheel in 2 parts, 2 coats for everything, face down to start. I then flipped it over and painted the face with 2 coats, about 1 hour between coats.

The finish was very rough but I have sanded most of it down and it seems quite good, except for the spokes and face of the wheel!! They are VERY rough, to the point that it was chewing up the 800grit wet and dry so I had to switch to 400grit and it's still quite rough on that, it feels like sandpaper. I thought that was just a characteristic of the paint and it would sand down to a smooth finish but having sanded it, there is now a potholed and bumpy finish. I don't think lacquer is going to solve this even though i've heard the finish isn't complete until it's been lacquered. I can only see that making things worse.

I shook the cans vigorously and timed myself for three minutes, I did it in a nice warm environment and it definitely isn't dust or dirt because there's a LOT of it and it's really really rough. I think it might be because I used the last bits of my first can to paint the front and it chucked all the dregs of the metallic all over my wheel.

Is this normal?

I'm planning on ordering another can (used 2 full cans on 1 18" RS4 alloy) and sanding down the current paint job until it's completely smooth/almost back to primer and then re-spraying it as I think it's gone wrong rather than just part of the process.

If anyone has used Wurth Silver Alloy products before and can let me know if you had similar results or if mine has gone wrong. I should add, it's not the whole wheel that is rough, only the center (where the cap sits) and the spokes just beyond that - but not all the way up them. The very edge of the wheel is lovely and smooth which makes me wonder why the spokes are so bad because the whole thing was treated in exactly the same way and every inch was spotlessly clean and smooth prior to painting.

Help!

Cheers


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## BLinky (Jul 3, 2009)

not normal no... what kind of temp are you working in?


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## neil.knapp (Sep 27, 2009)

Good temperatures. I'm painting indoors - paint in my "entrance way" so to speak, all masked up with polythene so it's nice and warm - probably 15 - 20c

Thanks for confirming what I thought


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## TOGWT (Sep 1, 2010)

What prep' work was done?

*a)	Surface Preparation*
•	Ensure wheels and rotors are cool before applying cold water as this may cause them to warp. 
•	Hose off as much initial grime as you can. 
•	Rinse up into the wheel well to wash away road kill, mud and other debris. 
•	Use detailing clay and lubrication to remove any embedded contaminants 
•	Use a d-limonene (citrus) based cleaner to remove any road tar or oil. Apply P21S® Total Auto Wash to wheel surfaces and let soak in, agitate with a long-handled boar's haired brush before rinsing 
•	Spray P21S® Wheel Cleaner (Gel or Liquid) this cleaner is 100% acid-free and will not damage any type of wheel finish. (Gel for badly soiled and regular for normal soil) onto wheel rims and lat soak in (for badly soiled surfaces us P21S®-Red (422) or Sonax Wheel Cleaner both are formulated with neutralised acid salt
•	Used the P21S® Polishing Soap on the clean wheel to polish the lips, inner wheel, and face of the wheel. (agitate lightly on the clear coated parts)
•	Before finally removing cleaner, agitate with a soft brush and then rinse off


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## neil.knapp (Sep 27, 2009)

Well, I stripped all the paint off and got back to bare metal. I did this using Nitromors paint stripper and a scraper then wire wool soaked in nitromors (plus PVC gloves to stop my skin falling off).

This removed 99% of the paint and primer.

I then sanded it down with 80grit aluminium oxide paper to remove the residue left behind by the paint until the surface was free from paint and rough to accommodate the primer.

Filled any holes with Isopon Metalik filler, left to dry then smoothed down with 120grit aluminium oxide I think, or 240grit wet and dry.

I then washed the wheel with sugar soap, rinsed in the bath with plenty of clean and let it air dry.

Primed it with Halfords grey primer (2 cans of for whole wheel). Done in two coats, top and bottom - flipping the wheel.

Then sanded down with 800grit wet and dry (wet, soaked in soapy water for lube) until it was smooth again and an even cover had been achieved across the whole wheel.

Washed with sugar soap in the bath and left to air dry.

Sprayed with Wurth Silver Alloy lacquer. I used 2 whole cans. I used almost 1 whole can on two coats for the "interior" of the wheel (that's everything except the face as it was placed face down on a strut, resting on the center hub).

Sprayed in my "entrance hall", small room, covered in polythene sheeting + newspaper. Warm, dry, clean, well ventilated when I open the door (once paint has dried slightly).

I'm pretty sure it was the gunk at the bottom of the first can that has ruined the finish.

I've sanded it down with 400grit wet and dry and now it's all "dimpled". I shouldn't have used the end bit of the can. Despite shaking it up for 3 minutes (timed - as per instructions) I don't think there was sufficient contents in the can to mix properly so it just chucked a load of metallic particles on the wheel and destroyed the finish.

I've sanded it down to be completely smooth again (almost to primer) and have ordered another can.

I've going to clean it all up and spray it again but make sure I shake that can like crazy before spraying!

I've tried to be as meticulous as I can throughout the whole process so all I can put it down to is misusing the paint.

Any thoughts welcome though.


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## tony_rigby_uk (Nov 27, 2008)

i'm in the process of this although doing it abit different...

but how the hell have you used 2 cans on one wheel? add the cost of 
2x primers
2x paints
2x lac
thats how much? it'll be cheaper to get them professionally done


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## TOGWT (Sep 1, 2010)

*b)	Refinishing*
See also Personal Protective Equipment (PPE)

•	Remove the damaged wheel from vehicle. 
•	Deflate the tyre by unscrewing cap and pushing in valve, once the tyre is flat push the tyre wall down (gently) by standing on it, and then tuck masking tape underneath the wheel rim, working your way around slowly
•	Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.
•	Clean the damaged area with PrepSol and then sand the scratched or damaged area with Norton 3X Sandpaper (p-graded aluminium oxide grain) 60, 80 or 100 grit sand paper, sand wet or dry with a rubber sanding block. 
•	Use a tack rag and wipe the area, using a light pressure
•	Only use filler (Bondo Lightweight Filler 264 and Red Cream Hardener) if it's essential to the e repair, if used incorrectly it will flake and significantly reduce the effective life-span of the repair. Fill any minor indentations with Bondo, allowing approx 30 minutes before you shape / sand 
•	Sand the wheels until you've removed the scratches, `kerbing' marks and/or smoothed the Bondo filler flush with the wheel surface. 
•	Continue the sanding process using finer and finer grades of UniGrit paper, 220 or 320 grit and finally with 500-grit paper. 
•	For small hard to reach places use a Dremel Tool and a suitable sanding bit

_Note- If the above cleaning method don't finish to wheels to your liking have them bead blasted_ 

*c)	Repainting (cast aluminium ) Wheel Surface*

See also Personal Protective Equipment (PPE)

80% of all OEM wheels are finished with a powder coating, as it is the most durable finish you can use.The following will result in a durable re-finished repaint

•	Molecular Tech Coatings Inc., EFS-2500 aircraft paint stripper is environment friendly. It can get easily decomposed and is also non-toxic as well. In terms of chemical composition, there is no methylene chloride, no carbonic acid, and no formic acid present in the paint stripper. Hence, it is perfectly safe to use.
•	Prepare the surface by removing all sandpaper residues with a tack rag, wash surface and then dry thoroughly. . 
•	Use 3M Painters Masking Tape between the tyre and the wheel rim (or use Vaseline to mask the tyre from paint overspray) 
•	Wipe-down the wheels with DuPont Prep Sol and allow to air dry. 
•	Apply a thin coat of 1z 'Haft-Grund' Self-etching Primer to stabilize and provide an etched surface. 
•	Use at temperatures between 70 - 90.oF degrees Fahrenheit (.Do not use this paint in damp conditions)
•	Shake the can well for at least a full minute
•	Push the spray nozzle as you sweep across and release at the end. 
•	Spray on, spray off. Spray on, spray off; apply as a very fine / thin coat. 
•	Paint the wheels with two thin coats of silver alloy paint (Wurth German Alloy Silver Wheel) to ensure complete coverage
•	Allow air-drying; 1-2 hours between coats and then lightly sand finish, then leave to cure overnight. 
•	Finish with a clear lacquer paint (Wurth European Blend Lacquers) apply two or three thin coats of clear with about 20-30 minutes of drying time between coats to seal the silver metallic paint and add depth and gloss 
•	A allow clear coat to air-dry and then cure for 4-6 ours
•	Apply a sealant for protection 
•	If your axle/ wheel centres (hats) are cast iron, you may want to consider painting the hat area with some hi-temp black engine paint

*Product details *_Audi, BMW, Mercedes-Benz, Porsche, VW, and most other European OEMs use a cast aluminium alloy wheels. They're usually painted silver and have a clear coated finish.

1.	1z 'Haft-Grund' Self-etching Primer - bare metal (steel or aluminium) wheels should be primed first with a self' -etching primer and is lead and cadmium-free Applied under a topcoat of urethane paint provides a secondary method of protecting the steel from corrosion. This primer bonds to bare metal and forms a base suitable for synthetic resin, acrylic lacquer and nitro combination paints. A single can will prime two wheels
Warning - Do not use this primer on painted or clear-coated wheels where you are touching-up scuffs and scrapes. A self-etching Primer is for use only on wheels that have been taken down to bare metal.

2.	Wurth German Alloy Silver Wheel Paint (Aerosol) can be used as a spot touch-up or whole wheel repaints, one can is enough to coat two complete wheels. This paint is unusually user-friendly, it's a fast-drying lacquer that matches the standard allow wheel paint use by Porsche, BMW, Mercedes, VW, Audi and most other European OEMs. One aerosol restores two complete wheels. to match the OEM gloss of new vehicles

3.	Wurth European Blend Lacquers (Aerosol) - used for all German (silver) painted wheels, to match the OEM gloss of new vehicles. This paint is unusually user-friendly, it's a fast-drying lacquer that matches the standard allow wheel paint use by Porsche, BMW, Mercedes, VW, Audi and most other European OEMs. Wurth German Alloy Silver Wheel Lacquer can be effectively used for spot repairs or full wheel restoration. One can is enough to coat two complete wheels. For the best results, use at temperatures between 70 and 90 degrees Fahrenheit._


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## tony_rigby_uk (Nov 27, 2008)

that sounds more like it.... One can for 2 wheels.... more is not always better... infact more introduces cracking and peeling..


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## neil.knapp (Sep 27, 2009)

I was surprised by the amount of paint I used, based on other reports I thought i'd use a lot less.

I don't feel like i'm painting the wheel very heavily. For the first coat of primer I covered it until I could barely see the metal and that used one whole can of primer. I was wondering if I was painting too far from the wheel and simply wasting paint so I tried to move a little closer but i'm definitely within the recommended 10inches from the wheel.

I did two coats of primer over the entire surface of the rim (tyre removed) and it used 2 whole cans without problem. I could quite easily have used 3 cans.

Having sanded down the primer it wore through on some of the corners so wasn't as thick as i'd hoped (i'm aware corners are very sensitive to sanding). I'm really not sure how to use any less than I did - it felt wrong but the wheel simply wouldn't have been coated if I sprayed it as I was expecting to.

My other paint arrived today so i'm going to give that a go but can't until Thursday as I have company here.

It would definitely have been cheaper to have the wheels refurbed. I could have had all 4 'touched up' for £140ish.

I wanted to do this as an interesting project though and I was sure I could do an equally adequate job with enough time. It has certainly proved a lot more difficult than I imagined and I definitely wouldn't do it again.

I MIGHT touch up the kerbed areas of my other wheels but i'm tempted to just pay for the whole lot to be stripped down and re-powder coated. At this point £300-£400 to have my evenings and living room back seems like a fair trade.


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