- If one is using hardboard (Masonite) for backdrop or fascia, do you prime it before painting?
- Does painting plywood prevent expansion-contraction due to humidty and temperature changes?
Thanks in advance for your opinions.
Yup, I put on 2 coats of high-hide white primer on my backdrop. It then only took 1 coat of my blue to cover it.
I’d have to go downstairs and look at the can to see exactly which one I got, but it all came from Lowes. Primer was stock, the blue is from one of the color lines they have, tinted to order, I used not the cheapest base but the next one up. I used 2 coats of the primer because after the first oen dried, I could still see some outlines of the areas I filled in screw holes and the seams between panels. Second coat of the primer killed that.
–Randy
I didn’t prime my hardboard fascia. I roughed it up a bit with sanding sponges to give the paint some tooth, then applied two coats. Seems to be fine (then again, it’s only about five months old).
My backdrop is styrene, and I gave it the same treatment.
Unless you use a sealing paint or primer, painting will NOT seal the hardboard. Moisture can still get in and out, so the board will still expand and contract with seasonal humidity changes.
I’ve thought about styrene, what thickness did you use?
My backdrop is drywall, finished the same as if it were a room, including a primer.
Mike.
Yes, I primed mine with 2 coats of Pittsburgh Ultra before painting the backdrop. This was all done about 4-8 months ago so too early to tell if I will get any cracking due to seasonal variations or not, but my climate is VERY well controlled in my basement with a commercial-grade dehumidifier.
At one point I had posted a thread that ran for quite a while here about how to fill in the gaps between my masonite sheets before painting. I’m not a drywall guy so I ended up using Alex Flex flexible joint/spackle compound and sanding as close as possible for a smooth finish before priming and painting. It worked good enough for me. Not building a museum quality layout. I did not prime the back side, nor did I rough up the smooth side in any way before priming and painting.
Oh, the rest of my process - after installing it, I sand it to get rid of the fuzzies where the screws are, then I spackle it, then sand after the spackle dries. If it’s not smooth, a second coat of spackle and another sanding before the paint.
–Randy
Is styrene more expensive. I’m thinking maybe if I can find two sided Masonite, then it can serve as a back drop to a penninsula.
.080. Works great!
It’s a bit more expensive, but it’s completely unaffected by humidity swings, and it’s very easy to work with.
When I lived in Annapolis, I bought a 4x8 sheet of 0.03 for around $23. Now I live in VA and Richmond is a couple hours away. Probably could find it there but a sheet of masonite is $9 at the big box stores.
I considered painting the walls. A gallon of home depot paint is $30 but I would have to do 2 coats. I have a bad rotator cuff and pouring a glass of wine hurts. I’m not up for repainting the walls.
I’m also neither good or fond of drywall mud, but the builder of my current house left me a half a bucket. At my previous house, my son finished the basement, but not a closet. My wife and I did the taping and we were a mess, by the time all the sanding was don.
You should have seen my basement the day the contractor sanded all the walls after the mudding and taping. Couldn;t see 5 feet in front of you, with all the lights on. Even the lights were hazy looking, no longer round bulbs but rahter obscure bight spots (temp bulbs wired in untilt he drop ceiling was instealled and the LED panels hooked up).
Got to sand the masonite, the paint takes better if the surface isn’t perfectly smooth, plus it seemed like the best way to get rid of the fuzzies around the screw heads. You won;t really see where the screws are once the benchwork is in place, but it was easirer to paint if the whole surface is smooth. That sanding did make a lot of brown dust, though the main problem was frequent changing of the sandpaper on my small sander. Most of the dust stuck to the surface - wiping with a damp cloth cleaned that off (I used shop towels, because it was messy, just dampen, wipe until saturated with dust, throw out, get another - regualr paper towels tear too easily). The sanding after the spackle, I generally only smoothed out the areas that got spackled to blend them into the masonite surface. That makes a good bit of white dust, but nothing near like doing a whole wall of drywall seams.
Hard to beat masonite on price. I think it was even less than $9 a sheet at Lowes by me, and since my spacing between decks is 16:, one sheet gives me 24 linear feet. I just have them cut it on their panel saw, even though I have the Kreg jig for my circular saw. It’s just easier - I usually buy 4 sheets at a time and they zip through it quicker than I ever could, and cut down it’s easier for me to carry into the basement.
I had grand thoughts of using something like aluminum roll for a continuous and seamless backdrop and all that but since I am building in stages, it would have been hard to place it all in one go. And I found some floor underlayment that was even cheaper than masonite and gave it a try. On an inside curve, it bent in ne
You definitely have to prime the filler. I gave a very quick and I mean quick, probably one pass with the sandpaper and put on the Home Depot sky blue.
Can’t see my joints, go ahead get as close as you like.[(-D]
My layout’s backdrop is mostly the drywall which was used to finish the room’s walls, but it’s painted only where it’s above the benchwork - all of the walls will be re-painted when the layout is removed.
All of the 10 corners (both “inside” and “outside”) of the room are “coved”, using 1/8" Masonite, and were painted, like the drywall, without primer. All have been in-place for over 30 years, with no cracks or popped screw-head plaster, nor any separation of the drywall taping…
I do intend to eventually paint the fascia, too, but there are still a few more control switches to be added.
Wayne
Put me in the primer camp. It also speeds up the process IMHO because less coats of paint are needed at the end of the day. And yes, humidity swings will affect masonite. We’ve seen it at the club. Adding extra screws and buying a dehumidifier fixed that problem.
Simon
You can avoid the dust cloud by using a wet sanding pad and rinsing it frequently in a bucket of clean water. Just don’t get it too wet or you will take off too much of the dried mud. Use a light touch when sanding.
I tried that when finishing my basement and it didn’t go well at all. Tried varying degrees of moisture and pressure and either it didn’t seem to remove/sand or it took too much off and then I had to re-apply another coat of drywall mud and back to dry sanding.
But since it was just me, it mostly dropped to the floor and I just had to keep sweeping or shop vaccing. I’m pretty good at drywall tapping and mudding and sanding, but the wet sanding just didn’t work for me and I did give it a go.
After doing all the walls, I decided a suspended ceiling was the way to go - didn’t want to be installing, mudding and sanding drywall on the ceiling! The boxed in crossbeams and ducts were enough.
Whether to prime or not is quickly becoming a moot point. I was at Lowes recently and it is getting hard to find paint that is not paint+primer.
My old house had a drywall ceiling in the basement - and I think they are the dumbest idea ever. What’s up in the joist space? Why, all your plumbing and electrical, of course. Good luck fixing anything. It’s bad enough all my electrical lines to the main panel run through a drywall (fireproof type, required by code) ceiling in my garage. Main reason I had a sub panel put in when I had the basement done - I now have a few spare breaker slots that I can get to just popping out drop ceiling tiles and running wire. And it made the job cheaper for the new wiring in the basement, the contractor only had to run one (ok, a larger) wire across the garage, instead of trying to fish 4 through there.
–Randy
I tried Behr Paint + Primer without priming ONCE, and was not happy with it.
Kilz-2 primer goes onto everything I do.
Shampoo + Conditioner combinations do not work as well either.
I am 100% in the prime-it-first group.
-Kevin