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>>Hola!>>I was given an old aluminum Cannondale frame that has paint scratched off in several places. I was thinking of removing the paint and leaving it as is (no paint). Is there any reason I can't do this? Also, how would I remove the paint cheaply and painless to the frame?
>Most Cannondales use a powder coat instead of paint. Paint can often be sanded off with emery cloth. Powder comes off also, but much less easily.
>I have done this on an old 'dale, but it is really best to find someone with a blast cabinet (using plastic media, not sand!) to remove the finish, as it will be tricky in spots. Once removed, the bare aluminum is vulnerable to things like finger prints and smudges. When I did this, the guy who removed the finish (who is also a bike painter) recommend I use Pledge to keep the bare aluminum looking nice. I gave the frame away, so didn't have a chance to try out the Pledge.
>If you don't go with a sandblaster, you can buy some nasty toxic goo called Jasco Epoxy and Paint Remover (at Home Depot) that will take off a powder coat, but it would be a pretty nasty project. Make sure you wear gloves and it probably wouldn't hurt to wear a respirator, or at least do it outside.
Many people don't realize that, though it doesn't turn orange, aluminum can and does corrode! Leaving it completely naked will eventually weaken your frame and could lead to stress cracks.
If you don't want to have to worry about a paint job, or if you just like the look of a bare nekkid frame, I'd recommend stripping the paint as per the above comment and applying a clearcoat. I have an old steel frame I sandblasted and coated with shiny clearcoat, and I think it's beautiful. If you don't like shiny, you can get matte clearcoat that mimics the "naked alum" look but still offers protection for your frame. Multiple thin coats are best.
Have fun! Nothing like fixing up a bike.
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