Painting Aqualu tub

[Gus]

I'm going to be coating the interrior of my 40 with durabak (one of those do-it-yourself poly bed liners) fairly soon, my problem is I'm worried about how well it will adhere to the aluminum tub. I POR-15'd the uder side of the tub, it peels of VERY easily and I meticulously followed the directions word for word and then some. What do you guys recomend or what have other Aqualu owners done. Any suggestions would be appreciated.

 

[kling-on]

on aluminum you would have to ruff the surface up ALOT and get an etching (sp) primer to hold first then the durabak will hild to the primer most of those prodects need "something" to hold on to ... look for a primer that works with alum

 

[wdorry]

PPG makes an etching primer that you use under the sandable primer before you paint. You need to talk with a PPG store rep and they can tell you if it will work for the bed liner material.
HTH Bill

 

[Gus]

Thanks for the input guys, I appreciate it

 

[Sparky_Mark]

My sentiments are similar to WDORRY's. There are several professional paints that will work with aluminum (POR-15 is not a professional paint system that has been tested to the same standards that the larger companies use).

I have used a PPG product and have had good results (do a phrase search for "frame paint" and "bed liner", there's a lot of good info), but there are other paint suppliers that have good products as well. Check out Sherwin Williams, Dupont, and Sikkens "Automotive Refinish" suppliers.

My advice is to look to a 2 part urethane epoxy primer that will adhere to aluminum. The data sheet will call out several properties (what surface the paint was designed for, it's corrosion resistance, UV resistance, harndess, temperature limitations, etc.) as well as what coatings are suggested for top coats. Make sure you get a data sheet!!!

Since you are using Durabak, none of the paint suppliers will guarantee chemical or mechanical adhesion (they would have to had tested that particular combination, which isn't in their best interest to do so). However, they may be able to give you suggestion on which primer to use. They may give you a concern with the nature of Durabak being a 1 part coating. I would suggest a 2 part urethane coating like SEM or gator guard to name a few. They are better in every aspect.

You can get an undercoating gun from Harbor Freight pretty cheap (like $10), it would make the bed liner application much easier, faster, and consistent.

Some say that prep is the most important step, but research shouldn't be overlooked. It looks like you found out the hard way with POR-15 (my sympathies, I'm sure you spent a lot of time on the underside).

Good luck!

 

[The Dude]

Unfortunatly the POR-15 is junk. You will have to remove it all to fix the problem.

As with any coatings system the prep is 99.99% of the battle. Without it your sunk. You need to sand everything, wash it, rinse it, tack it and then use a self etching primer for aluminium then an epoxy, and then the bed liner. Most sytems should allow you to spray wet on wet so no sanding between coats.

Personally, It would use a cromate etching primer then I would spray an epoxy like PPG's DP40 on the tub and then put the bed liner on top of it. If you get to the epoxy with the bed liner before it get hard, you should be able to top coat it with out sanding and maintain good inter-coat adhesion between the two products.