Spray Help Needed!

[Prashun Patel]

I doubt it’s your gun. I had once the second coat craze up within minutes of application. I scraped it off, let it dry, then went on with the product and it worked.

[Warren Lake]

what the temp of the room when you are spraying
what are the working temps of the material, there is a range
do you have the P sheet on the material
whats the temp of the coating you are spraying
whats the temp of the top you are spraying
what is the viscosity of what you are spraying, furniture factories use a viscosity meter and adjust the time so its the same all the time and they get the same results, they dont gamble when doing volume
do you you have the right needle nozzle combo for that material, Too big is better than too small,
what is your pressure
how open is the gun, full or turned in some amount, what is your fan set to,
did you spray a test pattern
what is your air flow are you pulling air in to the room when you spray, if you are pulling warmer air it may not level or you might get solvent pop, I see non of that there,

I dont know that finish or your spray gun but you have peel there. The parameters above all affect your finish plus whatever didnt come to mind. Then if you have that together Murphy will participate and you will find a beard hair in the finish or water might drip from your spray mask. You would think with covid and all going on the in the world he find a new occupation.

If you have a soft block and sand it with that you might not level that peel. Pay attention the grit and type of block you use.

[Ed Gibbons]

Update

I did a lot of sanding to smooth out the orange peel. Grit sequence was 180, 220, 320. 000 steel wool, 1000. Followed up with 3 very light coats about 1.5 hours apart. Came out nice. This was the first time I sprayed a large flat surface (60” by 36”). That was part of my issue, learning how to spray on a surface that large. This time I also held the spray gun closer to the surface with the nozzle pointed directly at the surface.

Thanks everyone for the help and encouragement.

[Prashun Patel]

Ok, so it indeed WAS orange peel. Because if it was crazing or alligatoring, the finish would have been crackly and wouldn't have bonded well with the first coat; it would scratch off messily when sanded.

Sounds like your issue was just too thick a coat. The Earlex and the HF/Rockler/Woodcraft HVLPs are tricky because you can't really throttle back the air. This makes balancing the flow and the speed of movement a little tricky.

In the interest of diagnosis: did you by any chance go over the finish a couple times on the 'bad' coat? In your room, is the air flow high? Was the temperature of the room or the finish kind of low? These things can impede the flowing out of the material.

[Ed Gibbons]

Did not go over bad finish. Shop is in basement and I’m guessing temperature is approximately 65. Not much air moving. I think I may upgrade my sprayer. Any recommendations on that would be appreciated.

[John TenEyck]

Did not go over bad finish. Shop is in basement and I’m guessing temperature is approximately 65. Not much air moving. I think I may upgrade my sprayer. Any recommendations on that would be appreciated.

EM-8000CV should spray fine through an Earlex with a 1.3 - 1.5 mm N/N set. It's viscosity is pretty low at about 35 seconds in a Zahn #2 cup which is just about the same in a Ford #4 cup, and that's low compared to many WB finishes. I really doubt you need a new/better gun to spray that stuff well. What you need is good technique, which only comes with experience, and maybe to add some Extender because turbines produce hot air and that often causes problems with finishes setting up before they have a chance to flow out.

On large surfaces it's important to spray from end to end, overlap your passes about 50%, and work from front to back, towards the exhaust fan. The gun should be close to 90 deg to the surface. I set the fan wide open on my gun, almost always, and hold it 8 - 10" from the surface. Lighting is critical to success. If you can't see the wet line you are doomed. If you don't have a wet mil gauge spend the $3 or 4 and get one and use it until you know what 3 - 5 mils looks like.

John

[Warren Lake]

sometimes hard to tell from photos but the peel showed in that photo. Id have to question your sanding process. Why so many grits? Normally depending on the finish its one grit and whatever 280 - 320. Id normally sand once with 320 before a second clear coat on a pre or post cat. If it was a really hard coat and heavy peel maybe drop down a grit. Why the steel wool? and 1000 grit? Sometimes steel wool can leave shards and you have a pretty open pore wood. Most finishes want tooth and need sand scratch there. Thinking back to Nitro when the next coat burned into the one below. The good old days

[Ed Gibbons]

sometimes hard to tell from photos but the peel showed in that photo. Id have to question your sanding process. Why so many grits? Normally depending on the finish its one grit and whatever 280 - 320. Id normally sand once with 320 before a second clear coat on a pre or post cat. If it was a really hard coat and heavy peel maybe drop down a grit. Why the steel wool? and 1000 grit? Sometimes steel wool can leave shards and you have a pretty open pore wood. Most finishes want tooth and need sand scratch there. Thinking back to Nitro when the next coat burned into the one below. The good old days

Definitely overkill on the grit sequence. I wanted to take off as much of the finish as I could without scratching the wood. Definitely the lower grits took off more but the higher grits appeared to help. Bottom line I need to improve my spraying technique and not rely on post spraying sanding.

[Warren Lake]

not just overkill might work against you. I would look at the sheets for that finish.