HVLP and poly

[Rick Beko]

I have a PC PSH1 HVLP spray gun that has been sitting on my shelf for over two years and it is time to give it a try. I will be running the gun from a compressor with an inline filter to remove an contaminates from the air line. The project is to apply Minwax Fast-Drying Polyurethane onto two hard maple cabinets that have Watco danish finish applied....that is after the Watco dries for 72 hours. Here are my two questions:

1. Has anyone tried spraying this type of Poly successfully? Any suggestions on the nozzle size and how much to thin? Can I store the left over poly in a jar for the next coat?

2. Should I be using something else? I need durability and water proof.

Thx

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[Steve Schoene]

Even "fast drying" polyurethane isn't really fast enough for good spraying, though I'm sure there are some that have been successful with it. Most however, are painfully aware of how much sticky mess is left on all the surroundings. And, they it will still collect enough dust to require rubbing out even for pretty casual applications.

Solvent finishes such as shellac and especially lacquer spray quite well, but have the challenge of needing ventilation that avoids the risks of both flammable, even explosive, solvents, and the dangers of breathing those solvents. Some of those--conversion varnishes for example--offer lots of durability, though are very hard to repair.

Waterborne finishes designed for spraying--Target, Fuhr and Enduro all have good examples. No explosion risk with these, and though you still don't want to breathe the fumes, it's easier to provide the necessary ventilation. Check out www.homesteadfinishing.com (http://www.homesteadfinishing.com) , Jeff Jewitt's company, for lots of good information.