[Ian1932]

Painting Over Water

Im trying to contribute to this site with things i know about. I thank everyone for helping with my projects!

Most would have never put any though into this. This is 100% true always!



Helpful painting tips... I have found over the years of painting there are simple things you can do to make sure things go as planned. I have painted professionally architectural mill-work and steel components for 25 years. Hopefully this can help someone.

My friend is restoring a 60's mack truck. He took the frame and had it sand blasted. He had the raw frame in his dark cool garage. The following day after blasting he wheeled it outside and epoxy primed it, then Y2K, waited then 2 days and top coated with a black chassis paint. When he was done it was really nice for a heavy truck frame. He started to assemble. About 2 months later little brown dots started to appear, kind of like it was bleeding. This is because he painted over water!

If you have ever taken a cold pop outside, or beer for most, and shortly after the can had beads of water on the outside. If you take a slightly warmer beer outside, it will get condensation as well but just not as bad. If you take a ever so slightly cold beer outside you may not be able to see or fell the water, but it is there! This is caused by the can being colder than the surrounding air temperature. Just like a fresh sandblasted pc of steel, this will also do the same thing!

IF METAL IS COLDER THAN THE IR TEMPERATURE IN THE ENVIRONMENT YOU ARE PAINTING IN, THE METAL IS WET!

The tip is to make sure that the metal you are painting is always WARMER than the air outside or in your shop. Out west, in Las Vegas this might not be an issue because the humidity is so low out of the gate. In places like TN or PA the humidity is generally pretty high even though on a 70 degrees and feels so nice. There is still plenty of water in the air to screw up your painting.

The solution is to "hot box" before you paint. If you are painting a frame you can build a cardboard hut around it and run a heater in side all night the day before (picture below). Or, you can put things in the oven, even heat them with a propane torch or ? I don’t mean to paint them while they a blazing hot but 5 or 10 degrees warmer than outside.

There have at least 5 times where i myself saw a frame in primer with rust poking all through it.

Some think a self etching primer is the key, this is not true. The idea is to hurry up and paint a 100% dry pc of metal and seal of with an epoxy that will lock out moisture and air completely! If there is no moisture and oxygen, rust cant happen, you need both components for rust.

I really hope this helps someone getting ready to paint!