# Water base over sheet metal.



## fishnpaint (Mar 20, 2018)

Title says it all, got a client demanding water based paint for a metal building. 
Problem: Have had some bad luck with the drying process and the paint still being tacky.
1st Process: I would DA the rust and surface of the metal, grind welds, fill gaps with Bondo and then easy sand, and clean with laquer thinner and a final clean with wax and grease remover, tack cloth. Shot Paint through conventional air sprayer. 48oz water base paint (resilience), 6oz water. Paint would not dry and travel log didn't show client bought primer. In our shop the past week weve had 81% humidity and average temperature of 84°. I have no control over shops temperatures or humidity. Easy solution would be temp control and dehumidifier...but i can't get top brass to buy into it. 
2nd process : DA, Bondo/easy sand, grind welds, cleaned with soap and water, dried with lint free rags / heat lamps, cleaned again with TSP + dried with lint free rags, wax and grease remover. Shot with conventional air sprayer. Coated with all surface enamel primer, 48 paint 4 oz of water. Humidity at 79% air temp 82° . Paint still tacky 2 days later. Heat lamps have been on since yesterday. 
We have to follow travel logs because of budget, can't substitute things because client purchased materials, and dealing with engineers who dont know paint, who pick the paint. 
How would you coat sheet metal have it dried and able to touch in 2 days ? 
Unfortunately I can't take pictures because of company policy. 

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## PACman (Oct 24, 2014)

TSP residue. Never use TSP under a waterbased paint without a VERY thorough rinsing of the TSP. Regardless of what all the paint store newbs say.


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## fishnpaint (Mar 20, 2018)

Makes sense. I can't exactly wash anything that doesn't fit into a slop sink due to OSHA. 

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## Brushman4 (Oct 18, 2014)

This is what we had to use to prime any or all ductwork back in the day, it was some nasty ass chit! http://www.reconcoatings.com/paintdatasheets/97-687-tdb.pdf


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## lilpaintchic (Jul 9, 2014)

DTM.build thin coats.

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## Schwabbles (Jul 1, 2016)

Yeah you want to use a DTM,light coats. Like no more the 1.5 to 2 dry mills a coat. Fans and air flow is huge. Especially at night get those fans going when humidity is at its lowest


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## Brushman4 (Oct 18, 2014)

Polyclutch it, already!


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