Sprayed Versus Brushed Finishes on Cabinet Doors
Levelling is a race the material can lose
Every brush leaves ridges. The filaments shear wet material as they pass, so the surface arrives holding a corrugated profile, often 50 to 100 microns from crest to trough. Whether those ridges vanish is settled by two competing quantities over the following few minutes. Surface tension pulls the film flat, because flat is the smaller surface. Viscosity resists that flow, and viscosity climbs steadily as water or solvent leaves. Flow out therefore happens only inside the open time, and open time collapses fast on a Yakima afternoon in the high nineties inside an unconditioned garage, easily half of what the technical data sheet assumed at 77 degrees. A slow evaporating co solvent buys the ridges longer to relax. Heat takes it away, and they set as cast.
What atomisation changes
Spraying removes the shear entirely. The gun tears the fluid into droplets, commonly 20 to 50 microns, and they land with no directional history, so nothing is written into the film except droplet size and how wet each droplet still was on arrival. Two variables govern that. Pressure, whether a turbine holding four to six psi at the air cap or an air assisted airless pushing 800 to 1200 psi through a nine to eleven thousandth tip, and viscosity, which is measured rather than guessed: 18 to 22 seconds through a number two Zahn cup covers most cabinet materials, usually reached with five to ten percent reduction by volume. Too thick and the fluid breaks into coarse droplets that land half dry and cure as orange peel. Too thin and vertical stiles sag. Neither of those is a gun fault.
Recoat is a deadline, not a suggestion
Dry to touch and ready for another coat are unrelated facts. A waterborne cabinet product is often dust free within 30 minutes and recoatable at two hours, but a crosslinking material also carries a maximum recoat window, frequently 24 to 48 hours, beyond which the first coat has hardened enough that the next one can no longer bond into it chemically. After that it holds mechanically or not at all, and only if the surface is abraded first. This is where brushing quietly manufactures failure. Three coats go onto a rack of doors inside one day with a gun, comfortably inside every window. Brushing a kitchen section by section across four evenings pushes coats past the window with nobody noticing, and the delamination surfaces later as a topcoat lifting in sheets while the primer beneath stays perfectly attached.
Containing overspray in a house somebody lives in
Material that misses the door does not disappear. Transfer efficiency runs near 65 percent for a well tuned turbine and closer to 30 for a conventional siphon gun, so a third to two thirds of everything atomised is airborne. Wet overspray drifts and sticks. Dry overspray turns into fine dust that settles on floors, appliance tops and sills well outside the room. Containing it means doors and drawer fronts come off and go to a rack in a garage or shop, while boxes coated in place get a sealed enclosure: sheeting on spring poles, taped seams, and a filtered fan exhausting through a window so the room sits at slight negative pressure and air travels out instead of down the hallway. Masking an ordinary kitchen properly is six to eight hours before any lid comes off, and it is the first step sacrificed when a schedule slips.
Where the hours and the disruption actually go
Spraying is front loaded. Masking, setup and 20 to 30 minutes of gun cleaning per session dominate the labour, while the coats themselves take minutes: thirty doors are covered in well under half an hour. The household pays differently, in a kitchen with no doors and no drawer fronts for five to ten days while removed parts cure lying flat, which is the only reliable route to a dead flat panel. Brushing inverts every term. No enclosure, no dust past the doorway, and the kitchen stays usable start to finish, but application hours run two to three times higher, some texture survives regardless of brush quality or levelling additive, and the work occupies the middle of the house for considerably longer. Which method is correct depends on which of those two costs the household can absorb.