Originally Posted by KHeon
Screen size is 100". I could go bigger on the wall I have but I want a nice 3.5" border around it so I'm willing to sacrifice a tiny bit of size for aesthetics.
Well under those circumstances, even if you must aggressively remove everything down to the original Kilz-2, you haven't got all that much to worry about.
The object will be to get the surface virtually Glass smooth again. You could do that simply by Dry Sanding with a medium Sanding Sponge ( get a 3" x 8" Norton from HD ) using first a spot sanding technique on the blemishes, then a "sweep-sanding" technique across the entire surface. Vertical strokes that encompass the height of the screen...about 3 up...3 down, then move over 2/3rds the length of the sponge and repeat...on until you have gone across the entire surface.
Then do it again...and again...until under a bright light, directed from the side across the surface, reveals a uniform and blemish free surface.
If you can accomplish that, then re-prime with the Bullseye, you should be good to go with the remaining paint.
BTW....personally I suggest sticking with the existing paint and doing multiple Dusters from 14" away. With a 100" screen, each coat should be done in or under 35-40 seconds, even with the required 70% overlap. DO NOT second guess coverage. Just coat the surface as instructed and get the 'ell away from it. The eventual build up will present you with the results you desire
If the MDF has a drop off at the edges, get some extra pieces and ring the edges with them so as you cross over any edge (Top/Bottom/Sides) with the spray pattern, the spray does not encounter a drop-off. If it does, the edges will not receive a uniform amount of paint due to "vortex ing". (...a swirling of air that prevents paint from laying down smoothly.