spraying info

Posted by Jay Rice on Apr 20, 2007

for those who have helped and advised, here's what I found out about spraying varnish...

I borrowed an HVLP gun, and for a test, I sanded down my hatch covers. called Interlux for thinning information, and they said that I cannot use an HVLP gun because it will cause orange peel. also I needed to use the 216 special thinner (no more than 10%), and have a nozzle or tip size of .89-1.4 mm (which I never found on any gun).

they said that I can use a conventional spray system with a siphon pot. set the PSI to 50-60 and around 5-8 PSI on the pot. I've never set any PSI on the pot before (or heard of it), so I just put an in-line regulator at the gun, along with an extra in-line filter.

the great news is that it worked just like I wanted it to. no brush marks or runs, virtually no dust (and I sprayed them in my dusty shop). It flowed out perfectly. I can see were I was a little thin in one spot, but I can build it up in later coats.

the best part was the clean up. it was easier and used less thinner than cleaning a brush. I may still try the HVLP for a test. I have a 1500 SF shop and it got pretty hazy with overspray.

After all the research on PSI's, contacting the company, looking for spray nozzles, etc. I figured it was being overcomplicated and decided to throw some varnish in the cup and go. It worked just fine.

Anyone thinking of spraying should go for it. not sure if I'd buy equipment if I didn't already have it, but worth every bit of effort.