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Nope, no contaminants, AFAIK.

Maybe I should try try a different brand of mineral spirits. I currently use the odor-free kind that Home Depot sells.




That is really weird. As most folks have said... that is what things look like if there is a foreign contaminant on the surface. Where the paint is attract unto itself... rather then leveling out.

Could that possible contaminant be too much soap in the water you are using when wet sanding ? Normally you are suppose to use only 1 or 2 drops of liquid dish detergent in the bucket of water that you are wetting your 'wet sanding block' in.

That kind of mottling is what I would expect to see if the surface was soapy and you added an oily liquid on to it. Same effect as how a drop of soap in a sink of dirty dishes will spread across the surface of the sink water.

Another thought, regarding the soap used in the wetsanding is to make sure it is just a pure liquid soap and not one of these dishwashing soaps that has all kinds of additives in it to : make hands softer, put an aroma in the air, etc.

Ok... lets pretend that it is none of the above...

So what I would do with that bad puppy is this :

a ) sand that surface down with an agressive sandpaper and get everything LEVEL again. Yes.. even if you have to get things back down to the primer level.

b ) take an absolutely clean COTTON cloth, dampen with 100% pure mineral spirits, and wipe this area down. Walk away and let it fully dry for several hours.

c ) use the Rustoleum/Tremclad full strength to repaint this surface. Put the undiluted paint in your roller tray and roll your roller through it... using the upper part of the tray to really squeegee out any excess paint. Basically trying to minimize the amount of paint that is on the roller.

d ) Ok... roll this barely wet paint roller on to the surface we are going to try to cover. Roll it thin and work it around to get as much coverage as you can with this barely loaded roller. Walk away from the job for a day... let it dry and see if what you laid down on that spot stays flush or whether it tries to mottle up like you have previously seen.

e ) IF the paint doesn't mottle, then repeat step C again. Hopefully the initial layer will serve as a good foundation on which to lay down another thin layer. Get it on, get it on thin, get it on even... then walk away for another day. Hopefully by giving it plenty of time to dry, this will eliminate the curing process as being the reason for the mottling.

f ) IF the paint did mottle... I would be personally pizzzzzzed off. I would probably sand it all off again... and then break out my handy dandy propane torch. I would out of frustration BURN that surface ( carefully ) with the crazy hope that 'whatever is causing the problems' would probabbly not survive a burnoff. The I would go back to step A and see if the burnoff got rid of whatever the mysterious mottling is being caused by. ( tee hee.. I bet you thought the use of the torch was without a legitimate reason ). NOTE : If it comes to using the torch... clear the work area and keep a running hose of water handy...

Marq

Last edited by Marq; 08/31/09 04:26 PM.