Originally Posted by arrabyla30
I guess I will stick with the "New" Behr 1850 UPW Flat. Previously I had great results using Valspar Ultra Premium Interior Latex Flat Enamel Base 1 (210170) so I may go that route. Yes, I am using the RS-MaxxMudd LL formula.
Thanks again for your help, its greatly appreciated!
Interior Enamels will often still exhibit the very slightest degree of sheen because they tend to dry into a denser, tighter surface coat....therein reflecting a small but noticeably higher degree of light. The use of Flat Enamel is good for circumstances when a darker Gray is used, and efforts to maintain gain are needed. It also is a more durable surface...and that can't be a bad thing in many cases.
But using a dead Flat paint for a base is a way to be certain that it will be far less likely that you will run into any broadly observable Hot Spotting.
Originally Posted by MavTrav
Thanks for the fast response.
What I have read says to do "Dusting Coats" (3' per Second vertical strokes, 18" away with 70% overlap). How many coats would be necessary, and how long is the dry time in-between coats? The last thing I want to do is botch the application.
I have never advocated doing "Vertical Strokes". ALL rows are horizontal, with the aforementioned 70% overlap.
Up to the first 3 coats, the surface will still look "Stripey". That's normal because your simply not putting up enough paint to effect total coverage and any spot that gets any less paint will show up as being lighter. But of you are diligently applying using the 70% overlap rule, things really even out by the 4th-5th coat. 6-8 Dusters usually effect total coverage. Going to a full 8 coats is perfectly fine, because if those "Dusters" are really "DUSTERS", you really haven't applied that much paint anyway.
A 3' per Sec. Duster coat will dry enough to allow the next coat in about 25-30 minutes.....and about a full 10 minutes faster if the Temp is above 75 and Humidity is low. ( I often heat up a room..so as to get the coats dry using a honest 25 minutes between coats...,but I always turn off the heat while spraying so no paint dust is sucked into AirReturns....and wait for 10 minutes after a coat before turning it back on to avoid blowing loose dust and hair against the screen surface while it's still sticky..)
But the surest way to tell is to wait a full 30 minutes, and then lightly tough the surface. If it feels dry and at room temperature, your good to go. If it feels dry to the touch but still feels cool....wait.
That said, sometimes I reverse and start my horizontal rows at the bottom. I also note the "Striped" areas and will adjust my starting point so the center of the spray pattern runs across the center of striped area that shows to have a less denser coating. As long as you only dropping / rising 30% above/below the previous row, it all evens out quite well.
But with such overlapping, and the subsequent potential to apply too much paint, that is why it's essential to observe dusting technique. Back when i used conventional HVLP, and during my "Break-in" period with the early Wagner CS, I thought I could easily enough see how thick of a paint layer to lay down....and adjust my speed and overlap to meet the task (...usually because I wanted to get done faster...) . It was risky....because of how thin the paint was...and I had just enough issues to switch entirely to "Dusting". Dusting has it's roots in trying to create a tacky surface on very slippery smooth substrates, such as Mirrors and Enameled Metal. So it stood to reason that if using the Dusting technique was strictly adhered to, even a rank NOOB should be able to spray a perfect surface the first time they break out of the Gate.