Unfortunatly, it’s the materials that is the problem.
Replacing plywood soffit. Out of 1/4″AC, bought BC. Don’t know if that is making a difference.
Used BM primer. Raised grain some (water-based primer). Flashing throughout the grain, dark to light. Started to put on exterior coat. No better.
Is AC any better? Will sanding the grain down solve this dillema? Should I use a different primer? Is Kilz water based better, because I really hate working with oil?
Thanks.
Glenn
Add a strap for easy carrying and pouring when working with 5-gal. buckets.
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Replies
Not the grade of A/C or B/C, it is the species of wood. Yellow pine or Fir? ohmy god, I hope it isn't luaun underlayment ( phillipene Mahog, or obeche).
And you do have the best side out RIGHT?
sand it. again. reprime, and top coat it twice. I like to prepaint 4x8 sheets before I ever get a saw out and cut to size.
It's not luaun. Not really sure of the species. Yet.I'm priming and painting at home before I even bring it to the job.Yea, I made sure from the getgo that the correct side is out.Thanks.Glenn
First off, the plywood should be either exterior grade or exposure 1. Don't use regular interior (exposure 2) plywood.
The type of primer used may be a factor. The old Moorewhite was best, but I believe has been discontinued due to VOC regs. Not sure what is the best replacement. You want an alkyd, though, not straight latex.
It may simply be crappy plywood, but 1/4" plywood always seems to have this problem to a degree. 3/8" would be a hair better and would have less tendency to sag.
Finally, remember that in most cases the soffit is only seen from 5-10 feet away. Pre-paint the material and select the best pieces for near the doors where it's most visible.
I've been doing quite a bit of painting lately, but I don't know as much as I would like.Is alkyd oil based?Are enamels oil based?I need a good book.I'm so confused.Glenn- Wishing he could come up with snappy taglines like Forrest.
Alkyd is a sort of halfway -- most of the good properties of oil based, and cleans up with paint thinner, but compatible with latex/acrylic topcoats. So long as it remains available it's the only thing I'd use for exterior primer.Enamel just refers to a paint that dries hard and glossy. Generally this is suitable for interior trim but isn't what you want for exterior use, except maybe for some trim details. Most commonly you want a satin finish acrylic for siding and a semigloss acrylic for trim, though a lot depends on personal preference and the type of surface being coated.It is confusing, in part because rule changes over the past 20 years (related to VOCs -- volatile organic compounds -- in the paints) have forced paint compositions to change.
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Ok. So, are acrylics oil based?It's been 15 years or more since I used oil. Clean up with mineral spirits or denatured alcohol? Soak it then rinse with water or no?If I remember, I let the junk settle, pour the good stuff on top to a new container, let the junk dry then throw it out. That the right way?Glenn
Tashler,Acrylics are water-based emulsions that clean up with water when wet, but cure waterproof. For exterior primer, you basically have 3 families of paint available. Water based (AKA latexes), oil based, and pigmented shellac (alcohol for thinner/cleanup).It sounds like you have water-soluble extractives that are bleeding through the latex primer. Using the alkyd primer over that will likely solve the problem, and it is what I would try first. The shellac is good for spots, but traps water vapor too well, which could possibly lead to wholesale peeling down the road.Bill
MDO makes a much more paintable surface for a soffit.
As for the plywood, you'll have to raise the grain first (the water based primer will do that), sand, then prime again. Then you can apply at least two coats of topcoat.
Prime both sides to minimize warping.
I use 3/8" AC pine ply
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Unfortunately, I have to match what is there.1/4" it is.