How to repair a Wheel Crack?
Did you hit a pothole or road barrier & got your Car or SUV wheel cracked? Instead of buying a new one, you might be wondering about the integrity & assurance of welding quality. Repairing a cast aluminum Rim of a vehicle is a matter of safety for yourself and your family who might use it. So, the weld repair must be very high quality, sound weld, and strong enough to provide safety & integrity to the rim. A cracked rim can be fatal, assume a car at very high speed and the wheel fails, and the results will be putting lives in danger.
Also, any crack or damage to the rim will lead to an air leak from the tire. such issues require immediate attention to rectify the problem.
So, Should you repair the Rim or replace it with a new one?
Well, honestly- as long as you can make sure what is the grade of cast aluminum & choose suitable matching welding consumables, you are good to go with a welding repair. Making a welding crack repair using matching welding filler wire, without any welding imperfection/ defects and welding of high quality are the essential tasks, we are looking at to ensure that the repaired rim is fit to use for the intended service & application.
First, which welding process is best for repair?
To be precise and cut the long story short- I will recommend using only Gas Tungsten Arc Welding (GTAW) or also called TIG welding. The obvious reason is- that TIG produces weld joints of very high quality and highly clean welds although very slow welding process. But, finally what matters is the welding quality in critical weld repairs. TIG welding of cast aluminum with pure argon as shielding & purging gas suits best for the welding crack or any other repair type.
TIG Welding Rod for cast aluminum rim or wheel repair
In the USA, Canada, Europe, and Japan AlSi7Mg0.3 are used mainly as the cast aluminum alloy material. ER5356 TIG wire is best suited for welding these grades as well as many other cast aluminum & forged aluminum rim grades used for the rim & wheel making. Always use a reputed manufacturer welding wire to ensure good quality & alloying are present within the standard limit in the welding filler wire. ER5356 filler wire in spool form can be used for the MIG welding of cast aluminum rim repair.
Steps for repairing the crack in cast rim
- The first and most important step before you commence the repair work is to identify the crack by its origin point and endpoint. Next, arrest the crack by drilling small-diameter holes (let’s say around 4 to 5 mm) at these points so the crack will not propagate further due to grinding or any hammering stresses as shown in the below picture.
2. Next, prepare a wider groove in the crack area, so the weld can be deposited onto it. Use a grinding wheel to grind it. Be careful to use gloves as aluminum can get hot without any change in color. so you will not know if it’s hot to touch or not unless u touch it with your bare hands.
3. Once the welding groove is prepared and the existing crack is fully removed, you are ready to deposit the silver color. Use AC TIG Welding, with current set up according to the filler wire diameter. Click here to find guide on choosing weld parameters. Make sure to fuse the weld fully with the cast rim material.
4. Follow the same procedure to weld on the other side of the wheel. Do not leave any underfill area as it can cause issues with the tire fitment later on. Complete the weld on the other side of the rim using the same filler wire & welding settings.
5. Next step is very critical as you need to match the rim surface by grinding the extruded welding area. Use, good quality and 200 Grit size emery paper to make a rough finish at first followed by 400 Grit size emery paper to provide a good quality surface finish.
This will ensure that there is a smooth transition between the welding repair area and the original rim material that will allow the right fitting and alignment of the wheel on the rim and there will be not any air leak during the use.
In all these tasks, welder skills are very important as welders need to be proactive & innovative. The actual cracks in the cast material can be of different shapes and dimensions and it might require changes in the repair procedure. A welder with good repair skills will be able to modify his approach to suit the needs.