Painting/Powder Coating Wheels

[pester]

Someone with more direct experience should comment on this one..... powder coating by everything I have read, is not going to provide the exact same sort of protection as paint.

You essentially strip the part to bare metal, then put an electrical charge on it to attract the plastic dust that will be the coating. Apply the dust, then bake the part to melt it all onto the part.

I don't see where this is going to provide a serious bond with the part. Smooth, slick, attractive.... but not that solid of a bond, in my view. I'm sure the coating is thicker than what paint will provide, so it should be able to handle a rougher subsurface, and give a smooth glossy surface.

As it's a plastic, it should bend and stretch more readily than dried paint, so on parts that may flex, it might be a good choice.

I would not want to rely on powder coat for corrosion protection. Primer tends to provide a barrier, and some sort of bonding at a molecular level to the surface being preserved. Paint tends to be designed to bond to that primer..... this makes both stick to the part very well.

Were it me, I would want the part preserved as well as possible, so I would not have to repeat the process. Epoxy paints are very tough, and bond well. Lacquer paints tend to chip easily, but dry very quickly. Enamel paints take longer to dry completely than epoxy, and are quite tough.

If your heart is set on powder coating, I would seriously consider the quality of the preparation that goes into it.

Cast aluminum rims get exposed to some pretty serious environments. all the puddles they go through, and the nicks that happen with tire changes, etc..... wrapping the rim in a plastic sheet that traps water underneath seems like a bad idea, without some sort of underlying corrosion prevention.

Btw. Aluminum does not corrode like carbon steel. No worries about it..besides how many wheels you see polished. Even frames. Unless you throw abrasive liquids to them they will not corrode. When they powdercoat. They bake the parts for the same reason. to create a good bond. Unless somebody dont know squat about powdercoating. There is no damage to it

sent from my s4

 

[RJ2112]

Btw. Aluminum does not corrode like carbon steel. No worries about it..besides how many wheels you see polished. Even frames. Unless you throw abrasive liquids to them they will not corrode. When they powdercoat. They bake the parts for the same reason. to create a good bond. Unless somebody dont know squat about powdercoating. There is no damage to it

sent from my s4

Aside from the fact that you've brought me back to a 4 year old thread..... Yes in fact aluminum does corrode. The oxides of aluminum are a grayish powder. When you have a polished frame, why do you think it gets dull? Guess what! Corrosion!

Aluminum boats, outboard motors, aluminum engine blocks..... ALL OF THESE CORRODE.

Powder coat does not form a chemical bond to the surface you melt it on to. It simply melts into the nooks and crannies. Water can be trapped, and cause corrosion over long periods of time, because it cannot dry out of that space.

Aluminum is one of the worst metals for making alloys. You get chunks (very small chunks) of other metals stuck in the structure. Those other metals have a different electrical potential than pure aluminum does. Add water, and you form a chemical battery just like the lead acid storage batteries used in charging systems.

Pitted aluminum is very difficult to spot structural flaws in. That's why so many aluminum frames get totalled by the insurance companies. They are a crap shoot, once they have been nicked, bent, dented heavily scratched. This stuff does not heal itself.

Your mielage may vary.

 

[bdevries]

Aside from the fact that you've brought me back to a 4 year old thread..... Yes in fact aluminum does corrode. The oxides of aluminum are a grayish powder. When you have a polished frame, why do you think it gets dull? Guess what! Corrosion!

Aluminum boats, outboard motors, aluminum engine blocks..... ALL OF THESE CORRODE.

Powder coat does not form a chemical bond to the surface you melt it on to. It simply melts into the nooks and crannies. Water can be trapped, and cause corrosion over long periods of time, because it cannot dry out of that space.

Aluminum is one of the worst metals for making alloys. You get chunks (very small chunks) of other metals stuck in the structure. Those other metals have a different electrical potential than pure aluminum does. Add water, and you form a chemical battery just like the lead acid storage batteries used in charging systems.

Pitted aluminum is very difficult to spot structural flaws in. That's why so many aluminum frames get totalled by the insurance companies. They are a crap shoot, once they have been nicked, bent, dented heavily scratched. This stuff does not heal itself.

Your mielage may vary.

I'd suggest a quick google on comparisons between powder coating and paint. PC is more durable, corrosion resistant etc etc etc. Saying water under the powder coating is a con is invalid. In ANY application, poor prep before painting or powder coating will make things go awry immediately or down the road.

Happy googling!

 

[Motogiro]

View attachment 52496



sent from my s4

Looks great!

 

[FinalImpact]

Lots of good points brought up in this thread.

1) do not powder coat (PC) mounting surfaces for bearings, seals, rotors. It will create clearance issues!

2) aluminum corrodes - steel oxidizes. As said, poor prep will kill any job. A proper PC job would include cooking the moisture out of the item BEFORE coating and curing takes place. It will cost more!

3) different products have different cure rates and durations at cure temp. It varies by the PC product applied. Read the details.

4) lots of people PC bike wheels. I'd personally would be doing some research first. I powder coated other parts using a products from prismatic. That color/product required 400°F for 15 min. That is the entire component must be at 400°F before you start the count down clock for product curing. Could that compromise a cast wheel - IDK! Be wise if you do!

5) blue wheels on a blue bike look very nice!