How to Repair Cracked Aluminum
by C.L. Rease
Cracked aluminum can be adequately repaired without welding using an epoxy embedded with aluminum. The aluminum particles contained in the epoxy will adhere to the cracked part, creating a permanent bond that will hold up in most situations. To ensure proper adhesion, you need to prepare the surface of the cracked part, as contaminants will interfere with the bond made between the aluminum epoxy and aluminum part. The amount of prep work required will depend on the type of cracked part you are repairing.
Step 1
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Apply the degreaser to the cracked aluminum part and allow the degreaser to remove the grease from the aluminum part.
Step 2
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Wipe the degreaser and freed grease from the aluminum part.
Step 3
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Spray the degreased cracked aluminum part with the 50/50 mixture to remove the degreaser residue from the surface of the part. Repeat the process if there is a lot of residue on the aluminum part.
Step 4
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Wipe the 50/50 mixture from the surface of the aluminum part and allow the part to air dry. Make sure that the area to be repaired is completely dry before proceeding to the next step.
Step 5
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Mix a portion of aluminum epoxy that will more than fill the crack that needs to be repaired.
Step 6
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Fill the crack with the thoroughly mixed aluminum epoxy. Work the epoxy onto the surface of the aluminum part with your fingers to ensure that there is no air located between the epoxy and the surface of the aluminum.
Step 7
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Allow the aluminum epoxy to cure as specified on the packaging.
Step 8
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Shape the aluminum epoxy with the 80-grit sandpaper to make sure that the cured epoxy does not interfere with the performance of the repaired aluminum part.
References
Things You'll Need
- Degreaser
- Clean rags
- Spray bottle filled with a 50/50 mixture of ammonia and water
- 200-grit sandpaper
- Aluminum repair epoxy
- 80-grit sandpaper