When switched to steel wheels for winter last fall, knew that I would be refinishing the OEM aluminum rims. 9 years of driving on salted roads by the previous owner, rims were leaking, pock marked, paint blistering, and overall looked pretty rough. After a winter of research came to the conclusion that refinishing rims is a hotly debated item. Was looking at dropping them off to get refinished using the following process:
https://detroitwheelandtire.com/pvd-what
Local rates are $150+ per wheel to refinish.
Looking at refinishing them myself, a lot cheaper but time consuming. Method that seems to consistent among many posts
-Sandblast
-Treat aluminum
-two base coats to adhere and seal aluminum
-Coat of finish
-Clear coat
Video showing basic steps in the process.
https://www.youtube.com/edit?video_id=Z ... rrer=watch
For the project wanted to use basic items that might be in typical garage, so others could complete without purchasing specialized equipment. The items many would still need to hire out are tire removal and sandblasting. As of 2015, most tire shops will remove a tire for $3-$7 per wheel, note if you plan to put new tires on, you may be stuck with the old tires at time of removal if you do not buy the new tires at that time (some states have funny laws about how used tires are recycled or disposal fees). Ask about disposal options for your old tires. Sandblasting requires some rather large equipment, typically large two stage air compressor, sandblasting rig, proper safety gear, large open space, neighbors that don't mind compressor running for hours on end, and large amounts of dust. Depending on your area, commercial sandblasting goes for $85-$150 per hour. Since these shops specialize in large volume blasting, they could have the rims done a lot quicker. On a good day a large shop might be able to blast 4 rims in about an hour.
Looking over various products, went with the following package. Big thing, whatever products you use, complete paint samples to confirm color match and primer, color, top coat compatibility. Sticking with one brand of paint will help.
Metal Prep - http://www.por15.com/POR-15-Metal-Prep_p_15.html
Base coat - http://www.por15.com/POR-15-Rust-Preven ... g_p_8.html
Top coat / color coat - http://www.por15.com/TOP-COAT_p_102.html
Clear Coat - http://www.por15.com/GLISTEN-PC_p_45.html
Started the process early spring by sandblasting the rims. Wanted to get the project done before bugs came out, landing on the freshly painted rims. Average set of 4 rims took about 4 bags of blasting media and about 3 hours to complete (a commercial shop will have larger equipment and could do in a fraction of the time). I recycled the media while blasting, making sure to get rubber, tar, and other material removed from the rim. If your tire shop left the valve stems, just use a sharp knife to cut the inner flange, then pull until the stems pull in two. Make sure to blast all the indentations and stem holes.
Next washed the rims to remove blasting media. After drying, sprayed with metal prep, let soak, rinsed, and let dry. While drying built a jig with saw horses and lumber to mount the rims. Rather than hang from wire, wanted to get all exposed surfaces painted continuously without gaps. Since the air inside the tire is usually low humidity and stays clean, not painting the inner center of the rim will have the least impact. If your tire shops fills the tires with nitrogen the impact is further reduced.
The paint I used has some special characteristics. The 2nd primer layer and color layer must be applied while the initial primer layer is tacky for proper bonding. If the primer layer dries before getting the next coat, it must be sanded prior to painting. Also the primer coat dries in 2-4 hours so re-coating happens quickly. The product I used it water activated, the more humid the day, the faster the primer dries. The primer is also UV sensitive so it must be top coated. For all paint layers I used gloves, long sleeve jacket, and respirator.
After the water dried, mounted the rims to jig and started to paint the primer coats. The product I used is self leveling, so brush strokes will disappear. However use a fine bristle brush. Initially I used a cheap natural fiber brush, the bristles were stiff and large, so if left deep brush strokes, which faintly showed up in the initial top coat process. (My test sample was laying flat on a cool day, so the brush stroked disappeared completely, when I painted the rims the temp was 15* warmer, humidity was about 40% more, and rims were vertical so the brush strokes didn't completely disappear) The finer the brush the better, you could then avoid wet sanding to remove brush strokes. Be careful when painting edges and lug holes, to avoid drips and runs. I started painting the back of the rim, working the product into holes etc, then moved to the front to smooth away any runs. After moving to the next rim, kept checking on the previous rim for drips or sags. Found using both a 1" and 2" brush worked best, 1" for lug holes and indentations, 2" for all other surfaces.
While the 2nd coat of primer is still tacky, applied the top color coat. This was out of a spray can, make sure to apply a light tack coat, let partially dry then work on two more coats keeping a wet surface to allow the top coat to flow (not drip) providing a smooth even color. I recommended practicing on a scrap piece with the spray can before painting the rims, will give you a better idea of coverage from the spray tip and how easy the product flows.
After the top color coat was applied and dried for 3 days, I wet sanded to remove any imperfections, dried, and top re-coated. If you are careful when applying the primer you can skip sanding and reapplying the color coat. At this point I also wet sanded the center caps so they would be ready for clear coating.
After the top coat dried for 3 days, applied the clear coat. The product I used had a quick set time and is also self leveling, so it can be brushed on. Mixed two batches of clear coat to prevent set time issues. I brushed on the 1st coat to rims 1 and 2, then applied the 2nd coat to rims 1 and 2 before moving to rims 3 and 4. After both clear coats layers have been applied, they are tack free in about an hour, but the product requires 3-4 days to fully cure. If not in a hurry, I would wait 7 days. From the sample I did, had some cool nights which delayed the final cure time. Plus your tire shop will likely lay down the rims or roll them across the floor, the harder the finish the better.
Overall the project went well. Achieved the main objective of sealing the aluminum rims, preventing slow tire leaks and paint blistering. Had some issues with using to course a brush, paint set time, and some over spray after wet sanding. This left the finish a little less than perfect. But hopefully these tips will prevent others from repeating those mistakes and needing to wet sand.
List of items used for 4 average rims:
Sandblast media - 4 bags
Metal Prep - about a quart
Base coat/Primer - just over a pint, so need a quart
Top coat - one can came close to completing, but need two in case you run into issues
Clear Coat - one pint
1" fine bristle brush - 4
2" fine bristle brush - 4
Clean metal soup cans -4
Good respirator
Plenty of nitrile or latex gloves
Overall, refinishing the rims with the products I used and doing your own sandblasting will cost about $200. Hiring out the sandblasting will add another $100 plus. The process used may still seem expensive, but rims take a lot of abuse, spin at over 1000 rpm, get hit with road debris, and cutting though rain and ice. The finish I used should well outlast the vehicle.
Anyone else strip and refinish their aluminum rims in the past? If so, how long ago and how are they holding up to weather/salt?