Spraying latex

[Jeff Scozzafava]

I built open shelves to sit on top of my base cabs for both sides of my fireplace. I am learning how to spray different finishes... by making mistakes along the way.

My latest is, when I sprayed the finish coat (Advance Satin) on the open shelves, I sprayed the front edge of the shelf (face frame on front edge of shelf) last... after I had done the shelf already. After an hour, I ran my hand over the surfaces... all of the vertical surfaces and upper surfaces are perfectly smooth... but the shelf surface must have had some over spray on it (or atomized paint that dried in the air and settled on the shelf surface) from when I did the front edge, since it is not perfectly smooth.

If I let it dry a couple days and use 2000 grit wet/dry paper with water and dish detergent to gently go over the shelf surface, will that help smooth it out without scuffing or dulling the satin finish of the paint?

I guess my alternative is to put a third finish coat on and make sure to do all the front edges (that spray across the shelf surface) first, and the shelf surface last?

[Justin Ludwig]

Wet sand ADVANCE with 220 or higher grit. It will smooth it out. The color will look lighter when wet and sanding but it will cure back to normal.

Dont put anything on the shelves for atleast a week. If it’s been rainy, wait 2 weeks.

[John TenEyck]

I agree with Justin except I would use a much finer grit, like 1000 or even higher, maybe even the 2000 grit you mentioned. You can always go coarser if it doesn't remove the roughness. Advance is a very soft paint and takes a really long time to harden. I would not put anything on those shelves for several weeks, maybe even a couple of months. It's a great product but drying and curing is its great shortcoming.

Next time you are faced with a spray job like that try to plan your approach so that the overspray never travels over previously sprayed areas. Advance has such a long open time I'm surprised you had problems with overspray roughness. Your comment about being able to wipe your hand over it in an hour is very surprising. When I've used Advance it was still tacky after 4 hours and took 16 hours before it was dry enough to scuff sand and recoat. Hard to believe we are talking about the same product.

John

[Justin Ludwig]

My thoughts exactly, John. Only reasoning I could muster is low humity and a heated environment. I won’t look cross-eyed at advance for 12 hours.
Because ADVANCE is so soft in the first couple days, I’ve had success using 220 sponge pads with water. If he’s just knocking down overspray roughness it won’t take much. 1000-2000 grit would take too long IMO. YMMV

[Jeff Scozzafava]

Thanks, everyone!

I am new to spraying... I think I am spraying the proper amount of paint... I have learned the hard way... sprayed to little and had it dry with uneven specks of color... sprayed too much and had it run a bit. I am spraying just enough so that with a bright light at an angle I see a uniform coat of paint and fine orange peel like finish. I have the pieces in a spray tent with fan... so may be the air movement is drying it quicker than normal? I shut the fan off about 10 minutes after spraying.

I did the second piece and payed attention to spray direction... doing the top shelf surface last with a good coat. After drying it still has some roughness to it... not much at all... but noticeably different feel than the vertical or underside surfaces... may be just atomized paint still in the air settling on the shelf surfaces?

[Justin Ludwig]

Airless or HVLP? If HVLP, tip size and amount thinned?

i tried once to spray ADVANCE with my Graco 9.5 turbine. Never again. Advance is best sprayed with an airless and a 210 or 310 FF tip.

[John TenEyck]

Airless or HVLP? If HVLP, tip size and amount thinned?

i tried once to spray ADVANCE with my Graco 9.5 turbine. Never again. Advance is best sprayed with an airless and a 210 or 310 FF tip.

Justin, BM Advance sprays great with a pressure cup HVLP gun, whether conversion gun or turbine. I can spray an amazing finish with it straight from the can.

John

[Justin Ludwig]

Hmmm. Maybe I didn't play with my settings enough. Since I own both an airless and a HVLP, my go-to is airless. I'll have to play around with the HVLP on the next project that doesn't require a lot of paint. Thanks for the heads up.

[John TenEyck]

Justin, note I said pressure assisted HVLP gun. I use a Qualspray gun with 3M H/O PPS cup. With a 1.5 mm N/N, 29 psi inlet pressure, and the cup pressure set at 5 - 6 psi Advance sprays like a dream.

John

[Jeff Scozzafava]

I have both the Accuspray pressure assisted gun and the non-pressure assist gun. I sprayed some doors with Advance with the non-pressure gun and got a great finish... BUT, I was always vertical and I had the pattern and air knobs all the way open. When I tried to spray my shelves which had side and upside down orientation required, got very little flow. I bought the pressure assisted gun and it solved the orientation problem... it also allowed me to back the air WAY down... and now I can spray a lot longer before my compressor kicks in... and using much less air keeps the blow back in corners to a minimum. I use a short hose on my 30 gal compressor and inline water remover and dryer. I used a 1.8 nozzle for my primer and 1.4 for the Advance. Worked very well. No thinning at all. I am a novice, so I don't have much to compare to... but the finish looks great!

[Justin Ludwig]

Justin, note I said pressure assisted HVLP gun. I use a Qualspray gun with 3M H/O PPS cup. With a 1.5 mm N/N, 29 psi inlet pressure, and the cup pressure set at 5 - 6 psi Advance sprays like a dream.

John

Ah! Yep, I’ll stick to my airless (Graco 495 PC Pro). Between my 2 systems I’m vested over $2500. I don’t need a third!