QuestionGary,
Thanks for taking the time to volunteer to be an "Expert" here. Your knowledge and experience are really valuable to idiots like me. Hopefully you can shed some light on a couple questions for me.
I've done a lot of painting with rattle cans. Mostly furniture, bicycles, motorcycles and localized car parts - door edges, wheel wells etc. I can usually get a very good looking result, but with insufficient durability. I currently have (2) bicycle frames I need to paint and I've been told that Dupont Imron 5000 is the best paint for this application. Is there a difference between the DuPont brand product and any other manufacturers of urethane paints? Specifically, what is it about urethane paints that make them more durable? Can you get the same high gloss ("wet") shine from Imron that you could get from a high quality laquer? Why is it that when I spend hours prepping a surface, very carefully sanding and polishing a frame (for example) that when I finally get the enamel color coat on evenly and finish it with an enamel clear coat, the finish is kind of brittle and can chip easily?
With a bicycle or motorcycle frame there is a lot of stone chip potential and possible paint cracking due to frame flexing - I'd like to get the most durable finish possible. I know it's a much different process, but how does powder coating compare with the urethane paints in durability, cost and ease of application? Can you achieve the same high gloss shine that you would get with a good enamel or laquer? Can you apply Imron or other urethane paint over a previously painted surface or does it need to be completely stripped and acid etched before painting? What type of primer do you use for urethane paint? Have you used this type of paint in the past? Can you recommend one brand over another when considering ease of application and cost? I've heard that urethane paint is extremely durable - what happens if I screw it up and need to strip it off again to start over?
I know these are a lot of questions, but I can't really find a lot of good comparitive information on the net - or at least I'm probably not looking in the right place. Any help you can provide will be gratefully accepted. Thanks again for offering your time to this service.
Matt Berens
AnswerHi Matt,
Sorry for the delay in response. Dupont doesn't have the market cornered on quality finishes. As long as you buy an equivalent quality urethane you can get the durability. PPG makes a finish called Concept.
As far as what makes urethanes better is the fact that they must have a chemical additive to complete the curing process. You typically can't find that in aerosol cans. However, there is a
Urethane Clear on the market that comes in an aerosol can called
SprayMax .
Typically with a Urethane you will get more gloss and depth than what you get from lacquer. Although, I have seen some beautiful hand rub lacquer finishes but the difference is how often it will need to be hand rubbed. With Urethane, usually one polish and it last for years. Whereas lacquer will need to be rubbed out every year if not more often.
Urethanes can be applied over existing finishes provided they are cured and sanded. For best results I recommend stripping all the old finish completely off and going back with a high quality
2K aerosol Epoxy Primer .
Urethanes can be stripped off using
Kleanstrip Aircraft Stripper or if it's fresh enough it can be wiped off with lacquer thinner (within 2-3 hours).
Powder Coating can be more durable depending on the quality that you buy. Powder is just like liquid paint in that there are multiple qualities available. Powder must be baked so to me that completely leaves out user friendliness.
If I were you and I was doing lots of small items such bicycles and motorcycle tanks I would consider using basecoat aerosol cans and then clearing with SprayMax 2K Clear Coat. This would give you good durability and gasoline resistance. You also should look at the whole SprayMax line of products. They have an
, a sandable aerosol 2K urethane primer , and a 2k urethane aerosol clearcoat .
Matt, if you have any other questions please feel free to ask a follow up and I will see if I can help you more.
