Durable and UV Resistant Coating for Non-Metal Surface

I use polyurethane marine varnish for clear doors...........the type that is made for sailboat decking, etc. Don't forget to do the top and bottom.

Hi kramarat

Thank you for the info.

Here, we have the following types of Top coatings:

1. Interior and exterior Clear Varnish (glossy), which is a one part "paint"

2. Clear PU Coat (Interior and Exterior), which is a one-part paint

3. Clear Auto PU Coat, which is a two-part paint

(All these are available in High Gloss, Semi-Gloss and matte)

What are the technical things that we should consider in the selection? How do we apply (the various auxiliary operations etc), so that the final finish is as good as the finish in an Automobile?

Thanks again

I wouldn't use the automotive stuff on wood. Expansion and contraction will likely crack it.

The gloss would be strictly up to the client. High gloss is almost never used here in the US. It makes it look like it's made of plastic.

I would use the best quality PU that you can find, with the highest UV protection.

Application would involve 2-3 coats with a light sanding and cleaning beween coats. 220 grit sandpaper works well.

For spraying, you would want to use a conventional cup gun or HVLP set up; thinning the material just enough to get a nice atomized spray, and running it through a fine mesh strainer before spraying.

Hi kramarat

Thanks again

We shall consider your advice and work carefully ... Shall come back after some experimental works and trials.

Best wishes and regards

pvhramani ....

Hello pvhramani.

You are already visiting with an excellent source of information, kramarat. I have some questions for you.

This door; is it an agrifiber core product?

Are the finishes you listed the only ones that will ever be available, or the only ones with which you feel comfortable using?

Hi Doorman

your Questions answered:

1. "Is it an agri-fiber Core product"

we are working on various material systems of Composites, wherein one ingredient would be a Composite of Agri-fiber system; others are still being designed and worked out (please see another Post: http://cr4.globalspec.com/thread/82710/Weight-Reducing-Structural-System-for-Panels)

2. "Are the finishes you listed the only ones that will ever be available.... ?"

The types of coatings having PU as the base ingredient are the ones mentioned. There are other coatings in Clear Formulations; but they are not in PU formulation. PU is the recommended system for our requirement. But we would like to have more on this matter too... "guidance"

Thanks again... pvhramani

I looked at your thread regarding panel cores, and had wondered if you were looking for door cores. For durability and long life under hard use, it is difficult to do better than the time tested mat formed particle board or stave lumber. These both have the disadvantage (if it truly is a disadvantage) of mass. Door manufacturers have learned that longtime dimensional stability is a must-have; when lighter weight is a desired characteristic, industrial hollow core construction is often used where the more common kraft-paper type cores are inappropriate.

For your consideration, doors that are sold in the US market should have (in fact, might be required to have) cores per the requirements of AWI sections 1300-G-6, 1300-G-7, 1300-G-8, 1300-T-3... there are many, many guides to door construction within. I regret, this (The Architectural Woodwork Institute Quality Standards manual) is a copyrighted document, so you must purchase a manual to review.

Hi Doorman

Thank you for your comments and observations. We are looking for such constructions not only for Doors, but also for various other Wood substitute systems. Please also visit: http://cr4.globalspec.com/thread/82713/Designing-Agrowaste-Composite-Boards

Thanks again... pvhramani