Getting a durable finish
05-23-12 | 10:20 AM
#26
framebuilder
Joined: Dec 2009
Posts: 1,788
Likes: 2,710
From: Niles, Michigan
From experience I have't found something better than old Imron in terms of chip resistance. I've got frames in my shop that I made and painted in the 70's that are still almost bullet proof. It is what was originally used on airplanes and commercial step vans that take a lot of abuse. Some of those "improvements" are to make it more environmentally friendly or increase profitability by making it cheaper or to make it easier for the painter to use. It isn't necessarily to make it tougher. When I've asked the Dupont reps about how long they will continue to make it, there objections were about its toxicity and that painters wanted something that set up faster. Like has been mentioned, Imron paint now has more varieties.
Keep in mind that the original Imron is the Dupont trade name for polyurethane enamel that other paint manufacturers make and sell as well. There is even a paint company that makes that type of paint a half mile from my frame shop. What brand of paint a person uses is often defined by what jobber is most convenient. The different brands of polyurethane enamels provide similar results but do require their own activators and thinners, etc. I like to use House of Kolor paints because they have a whole line of glamour paints including candies, pearls and chameleons. I'm not crazy about their clears as a final clear.
Keep in mind that the original Imron is the Dupont trade name for polyurethane enamel that other paint manufacturers make and sell as well. There is even a paint company that makes that type of paint a half mile from my frame shop. What brand of paint a person uses is often defined by what jobber is most convenient. The different brands of polyurethane enamels provide similar results but do require their own activators and thinners, etc. I like to use House of Kolor paints because they have a whole line of glamour paints including candies, pearls and chameleons. I'm not crazy about their clears as a final clear.
05-23-12 | 12:07 PM
#27
Senior Member
Joined: Dec 2005
Posts: 7,848
Likes: 4
+1.. imron belongs to dupont, this thing runs the same variety of colors of chromabase for example? Never seen a single shop around here carrying imron.
Browsing through a car forum there was a post by a Dupont employee. Looks like Imron is a generic label used on a variety of paints now. The reputation for durability came from their industrial strength paint that was maid in the 90s. Now most available-to-consumer "Imron" paint is just generic car paint. They also claimed paint science has come a long way and there is better stuff out there now.
05-23-12 | 07:12 PM
#28
Junior Member
Joined: Jun 2010
Posts: 13
Likes: 0
From: Evansville, IN
Bikes: Surly LHT, 1993 Bianchi Super Grizzly, Specialized Allez, Trek Soho, Schwinn Continental Fixed Gear, Schwinn World Sport
One thing that I haven't seen mentioned in any of these posts is the role that the hardener plays in two stage systems. Using the wrong ratio of hardener or too fast of reducer can cause the brittleness that you have experienced. I used to tint windows with car paint that holds up as well or better than vinyl, its a matter of getting the ratios right. Experiencing chipping (brittleness) is likely caused by poor prep work or a failure in somewhere in the application process. (Helpful, right?) If you are confident in your prep work examine the products you are using and your process. Make sure you are using the right products as recommended by the manufacturer. Also in the world of paint, cost is well correlated with quality products.
