curbed stock wheels
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twofourzeroSX
- Posts: 773
- Joined: Mon Apr 12, 2004 8:38 am
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curbed stock wheels
I curbed my front left wheel comming out of the bank today. Its not that bad, its just from a loose piece of curb. how can i refinish or make my 7 spokes look better?
Re: curbed stock wheels (twofourzeroSX)
Powder coating looks nice...
you cna take them to a wheel remanufacturing place and tell them what color you want, too...-Chet
you cna take them to a wheel remanufacturing place and tell them what color you want, too...-Chet
Re: (nismofly)
I quoted this from http://my.execpc.com/~davewrit/Powder.html
"Found your article most enlightening. A metallurgist friend told me a few years ago that things like aluminum wheel spindles should not be powder coated. He explained that aluminum billet material (6061-T6 ?) changed crystal structure at a critical temperature around 410 degrees F (as I recall). The thrust was that the heating step would adversely affect the strength of the material. Non-structural components would be OK, but not something that "holds the spokes on". The metallurgist is correct. Products like wheel billets, scuba tanks, etc. can be powder coated, but only with powders which cure below peak metal temperature of 300 degrees F. The magic temperature is about 275F. The crystalline realignment at 400 degrees F causes the previous ductile aluminum to become brittle. Imagine the catastrophe when an 80 cu. ft. scuba tank explodes under 3000 psi pressure after an unauthorized powder coat (this actually happened). To my knowledge, all Aluminum wheels and other strength-critical aluminum components are powder coated with these cooler curing powders.
Heating Al alloys above this temperature causes a granular rearrangement of the metallurgical structure resulting in a significant change of bulk properties. The tensile strength of the metal is dramatically lowered, much like a stress relief anneal on a
steel piece would do. The resultant metal is not as strong, nor will
pressure vessels made of such treated aluminum (e.g., scuba tanks) hold near
the pressure that they were originally rated for. Since wheels are essentially load-bearing structures, they should never be heated like this unless the alloy is known to tolerate it well. "
"Found your article most enlightening. A metallurgist friend told me a few years ago that things like aluminum wheel spindles should not be powder coated. He explained that aluminum billet material (6061-T6 ?) changed crystal structure at a critical temperature around 410 degrees F (as I recall). The thrust was that the heating step would adversely affect the strength of the material. Non-structural components would be OK, but not something that "holds the spokes on". The metallurgist is correct. Products like wheel billets, scuba tanks, etc. can be powder coated, but only with powders which cure below peak metal temperature of 300 degrees F. The magic temperature is about 275F. The crystalline realignment at 400 degrees F causes the previous ductile aluminum to become brittle. Imagine the catastrophe when an 80 cu. ft. scuba tank explodes under 3000 psi pressure after an unauthorized powder coat (this actually happened). To my knowledge, all Aluminum wheels and other strength-critical aluminum components are powder coated with these cooler curing powders.
Heating Al alloys above this temperature causes a granular rearrangement of the metallurgical structure resulting in a significant change of bulk properties. The tensile strength of the metal is dramatically lowered, much like a stress relief anneal on a
steel piece would do. The resultant metal is not as strong, nor will
pressure vessels made of such treated aluminum (e.g., scuba tanks) hold near
the pressure that they were originally rated for. Since wheels are essentially load-bearing structures, they should never be heated like this unless the alloy is known to tolerate it well. "
Re: (deezlins)
you can mitigate that problem by annealing the aluminum after you powder coat it, but I'm not sure how the powder coat would hold up to 900 degrees or so to anneal the aluminum, then you'd also have to wait about 30 days for it to precipitation harden back to T6, as it would be t0 after annealing (more ductile than T6)
All this heat treatment is obviously a bad idea for any machined part as the tolerances will get jacked up.
All this heat treatment is obviously a bad idea for any machined part as the tolerances will get jacked up.