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Discussion Starter #1 (Edited)
I needed 4 alloy wheels for my yet-to-be-bought summer tires, so I only pay for mounting and balancing once, and got a good deal on KiJiJi on a set for $100.00. They were quite beat-up from road rash though, but no dents or deep gouges, just bad paint and surface corrosion.

While waiting for decent weather and a chance to get at cleaning them up, I lucked onto a set of new tires, which included mounting and balancing, so I decided to mount them and do the repaint after. I was going to redo the wheels without the tires on, to save masking time.

Step one was giving them a good cleaning with soap and water, then getting out my faithful pressure canister sand blaster, laying down a tarp, and having at the sandblasting.

Here's 1 wheel after cleaning and before blasting.


Here's the same wheel after, and I kid you not, less than 45 seconds of blasting at about 110lbs air pressure, #0 sand


I estimate that it took less than 6 minutes to actually get all 4 rims down to bare aluminum. The set-up time and cleanup after meant the entire job was about 1 1/4 hours or so. After re-sieving the used sand, the 4 rims consumed about 3/4 of a $12.00 bag. This is with a pressure blaster, not a siphon blaster though - big difference.


Next was masking each wheel with a piece tight around the edge of the rim.


Then, I cut out a larger piece of kraft paper with a circular cutout just outside the taped part on each wheel. This is applied to each wheel, which I then spray, then move on to the next coat, remove and so on. I only put tape on the masking paper once during the entire operation.


This what the masking paper looks like applied at each stage of the painting.
 

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Discussion Starter #3 (Edited)
Before painting, I wiped each wheel down thoroughly with a pre-cleaning solution. I used some Sikkens stuff, but Dupont Wash & Wipe works good too. Then I sprayed a coat of self etching grey primer.


To answer your Q's, this job was to get 4 wheels looking good, not perfect, for the road, not for the local car show 'n shine. I just spray and move on to the next coat. If you wanted to, you could apply some surface finishing glaze body fill compound, sand out the imperfections, then re-prime, at this stage. I simply moved on to the silver base coat after letting the primer dry for about an hour. The base and subsequent coat of clear are both Wurth products, the BEST IMO for wheel painting.


For something useful to do while waiting for coats to set up, I removed the Toyota symbols from the plastic center inserts and buffed them off with 00 steel wool, then cleaner, primer, silver and finally clear coat. I had to grind off the melted plastic 'button' in the center of each symbol before they could be pryed off. I put a dab of Krazy Glue on after returning them to the painted discs.


Here's a last shot of the finished wheel on the car. Not show-quality, but then not a lot of effort either.


I'd highly recommend investing in one of these pressure blasters. Years ago, I paid over $350.00 for mine, and that was a bargain at the time. Today, places like Princess Auto in Canada and Harbour Freight in the U.S. sell them for about $125.00. Siphon blasters work too, but not nearly as fast and not as effective with scouring off rust, scale, paint, and residue.

 

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Discussion Starter #4
One caveat: The Toyota Owner's Manual clearly states never to sandblast alloy wheels.

What happens is the molecular structure of the alloy gets weakened from the sandblasting and can lead to catastrophic wheel failure. It can't be visually detected, but under a very high power electron microscope - the damage is evident.

Michelin also issued a similar warning regarding power washers, the pulsations can weaken the sidewall and ribbing structure - causing failure.
Now I find this out! I didn't know that. I'm not worried though. I just don't see how a 45 second scouring is going to weaken the metal. Actually, quite a bit of the original paint was still on the surface afterward. I also forgot to mention that I gave the insides of the rims a quick pass as well, just to get the road grime and brake dust off.

I'd think a thorough blasting in a cabinet, with the intent to get the metal ready for sanding and polishing, might do the kind of damage referred to. Anyway, I'm going to run with these over the summer regardless...but I'm going to dig further into what you point out.
 

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Togue superstar
00 Camry LE
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i want to repaint my steelies a glossy black.

How do you propose I go about doing this, besides sanding them?
What kind of paints and sealants will i need?
 

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Discussion Starter #7
The rims were $25.00 each. The owner said they came off his '96 Camry..

Re. other question on re-doing steel rims, I'd definately go the sandblasting route on those, if there is any significant surface rust. If you have the time and energy, a wire cup brush mounted on a grinder will do a nice job of prepping the surface for primer. Just go the same drill I described for the alloys: Wash, mechanical surface prep with a sandblaster or wire wheel/brush and/or sanding disk, surface prep with de-greaser (actually a good idea to use this before sanding/wire brush, so you don't grind the contaminants into the surface), prime, then fill/sand/prime again, or go right to your choice of paint. I'd use a high quality epoxy paint if you can afford it, to avoid road rash. Often the local paint store can premix it for you in a spray bomb, or it can be bought ready to spray.

I did some research on the subject of sandblasting alloy rims. There are plenty of places that advertise sandblasting as a surface treatment prior to painting, but no mention of what media is used. Softer media like walnut shells is mentioned sometimes, but also that it is painfully slow. Several discussions I read on forums like this one seem to discourage sandblasting, but mainly to avoid too aggressive pitting of the soft aluminum rather than initiating structural damage. I also couldn't find any mention of this in my owners manual either, but it's a '96 so maybe the rims offered at that time were different.
 

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Toyota-Lexus Fanatic
95 Camry LE
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Great DIY! That sandblaster is a must own...I can not begin to imagine what to do with it....! Great wheels for minimal investment. Good job!
 

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Canyon Killer
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reminds me of a time at autocross...

a WRX STi had powdered coated wheels, and when it went around a corner pretty hard, the wheel actually bent under the pressure... funny shit, only because it wasn't my car :)
 

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My other car is a Camry
Camry
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It's not immediate and it won't lead to total failure on it's own from 45 seconds of sandblasing.

It requires a number of factors, and a 'perfect storm' of events for this to happen. Say you drive it for many years and one day you encounter a high load and speed cornering condition and you hit a pothole - over time and through external circumstances you may see the worst possible outcome.

Note the Titanic could have survived the iceberg, what they found is the rivets had not been properly made (not the right alloy - slightly off, not properly heat treated or cooled ) after putting them under a electron scope. They manufacturer knew about it, but went ahead anyways, because it was so minor a detail - no one thought it could make a difference to be off specifications by just a minute percentage.

I actually met the principal who found the wreckage and did the engineering failure analysis.

What I have learned in 20 years of engineering is that the smallest things have the biggest consequences in outcomes.
Well said...

I always did it the hard way with sanding discs and hand sanding them for probably 2-3 sets of wheels I have repainted in the past. Glad to know my efforts have paid off...lol
 
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