In this part of the country (Mid-Atlantic), cars and wheels especially take a beating during the winter. Slippery roads, corrosive salt on the roads, and potholes that could swallow a small child wreak havoc on your auto. The cost to replace a damaged aluminum or alloy wheel on a new car can be VERY costly. With classic and specialty cars your wheels could also be obsolete and impossible to replace if you have a damaged wheel. I decided to show the process of repairing a badly damaged aluminum aftermarket wheel I have had stashed away for years.
The story of this wheel starts with a dishonest seller that told me that the set of wheels I was buying had one with light bends and a small, barely noticeable crack. What I received was a wheel that more resembled a stop sign than a mag wheel for a car AND it had a TEAR in the rim! The “small crack” was actually a large crack with the the surface being higher on one side and causing the lip of the wheel to have a high spot where it ripped and bent. This was probably close to 10 years ago before I could repair it myself, so I sourced another single wheel (paid out the nose for one wheel!) and squirreled this one away. Fast forward and now I’m ready to repair this wheel and share the basic process with you.
I started by sanding the entire work area on the lip down to bare, clean aluminum with 36 grit on the 1/4″ angle grinder. I then lit the Oxy-Acetylene torch up and began heating the entire area that was damaged. The first reason for doing this was to try and “burn out” any of the dirt, grease, or other impurities that would be on the surface or in the recessed areas that a grinder couldn’t easily reach. The second reason was that I wanted to “soften” that part of the wheel up a little so I could hammer on the wheel to flatten out the high part of the wheel where it was cracked. By heating the metal it will tend to bend back into shape and not tear further.
Once the damaged area was nice and hot I used a combination of a brass and a plastic dead blow hammer to level the areas out. This is a bit scary at first, wailing on your wheel with a hammer, but it’s necessary. Depending on how extensive your damage is and how long you’re hammering, you may need to reheat the area periodically. Luckily the damage on my wheel only took a few whacks to get it back into shape around the crack.
Next I needed to gouge out the crack on both sides so I could fill the crack and not just lay weld on top. This also lets us grind down into fresh aluminum that isn’t corroded. I used the angle grinder with a grinding stone and put a groove in the crack on either side that was about the depth of a 3/16″ filler rod. I then drilled 1/8″ holes in the ends of each crack to keep the crack from continuing later in life. Lastly I cleaned the entire work area with Acetone and let it flash off before welding.
I started by installing a gas lens kit on the TIG 200 torch and turning the gas flow up a bit so I could get the best possible gas coverage over the weld puddle. I started on the backside of the wheel next to where I’d be welding and dialed the clearance effect in. Every wheel and damage situation is going to be different and may require you to adjust the clearance effect. The idea is to get the as small and controllable of a weld puddle as possible with the puddle staying clean. If you see dirt floating in the puddle or a dark brown or black halo around the weld puddle you may be able to bump the clearance effect a little more positive. I found the magic setting on this job was right around -3 for clearance effect, pedal set to 160 amps max, a 3/32″ purple E3 electrode, #8 Gas lens cup, and around 20 CFH for gas flow.
I chose to weld the backside first as that area is hidden when done and I knew that if I had any contaminants pop out of the weld seam or settings I needed to dial in, I could get away with a little “uglier” of a weld (that doesn’t mean big booger welds are acceptable!). I did have some contaminates popping out as I began welding, but nothing too major on the backside. I immediately flipped the wheel over and began welding the front side while I still had some heat in the wheel to help the puddle flow a little easier. I did find that I had a very faint brown halo around the puddle on the front side, it could have been from contaminants that pushed through the seam from welding the other side, or possibly residue from the rag I used to clean the weld seam, but the puddle didn’t have any pits or dirt floating in it most importantly. A porous weld is BAD and WILL fail on a repair like this!
I started leveling the welds out with a flap disc on the angle grinder just to knock down any highs and do some rough shaping in the corners of the lip. I then came back with a 36 grit disc on the 1/4″ angle grinder and finessed and blended the weld seams into the wheel. This got the major damaged area filled and blended to the point in which you couldn’t even tell it was cracked before!
The next step is going to vary on how picky you are about the wheel you’re repairing. This involves leveling out the surface of the wheel and repairing any low spots from grinding, curb rash, or etc. On this particular repair next to the repair area and one the edge of the lip had been deformed when it cracked and after repairing the crack and blending the seam those areas were a bit low. The edge of the lip wasn’t as “crisp” as the rest of the wheel. This meant I had to add some weld as to those low spots. I like to grind the area out a little bit and push larger than needed dips of filler rod into that area. The idea is to “overfill” the low spots so you have plenty of material to sand back and level out. These particular low spots only took one pass of filling and sanding, but yours may take more. It really doesn’t matter how many it takes as long as the area is filled and blended in the end. I’ve seen high-end wheel repair shops that have built up an entire missing portion of a wheel lip with filler welds alone!
For this exercise this damaged area is repaired to the point of sanding and polishing or paint/powder. If you have the tools, time, and patience you can take this repair to the next step and put the wheel on a lathe and machine any minor high spots down or identify any low spots that need more filling. If you take your time with a straight edge, a couple sanders, and a block with sandpaper, you can get the repairs REALLY close without needing a lathe, but it doesn’t hurt if you have access!
This process is the same to repair curb rash, dings, or other damage to a wheel and can even be used on a steel wheel you want to save. I have saved a few wheels this way over the years and I’ve repaired countless curb rash damage before mirror polishing the lips of a wheel and it really makes the difference, because wheels can make or break a ride!
****Warning: Do not attempt this if you aren’t comfortable with your welding abilities. It’s always a good idea to have the repaired wheel inspected and balance checked by a professional before installing on a car.******