Tack cloths are usually reserved for really fine finishes such as furniture. Vacuum with a brush attachment then inspect for pinholes in the joint compound. The vacuum should be all you need.

How do you handle the pinholes? Do you try to fill before or after priming, when you can wipe off excess? They are a real pain.

You are way, way, over doing it. No tack cloth. Pin holes?
Prime and paint, all gone .How close are you standing looking for this stuff? Back away 3 feet and all will be fine.
Get to work and quit worrying

Well, if you had the all the paint coming off down to the wall board from bad adhesion, you might want it super clean, no dust, too.

The pin holes did not fill downstairs.

I see I asked this before.

"Pinholes in mud never fill with paint. Use spackle after priming, then spot prime, let dry fully, and paint.
Casey"

This post was edited by snookums2 on Sun, May 19, 13 at 8:45

Joint compound dust might cause lumps or bumps in the paint, but is unlikely to affect paint adhesion. There might be something else going on.

If the pinholes are that big a problem, maybe there is something wrong with your joint compound?

Apparently pinholes are a common and frustrating problem, even among drywallers. Some of them will need to be filled after priming.

Paint doesn't adhere to dusty walls. I don't think it matters what type of dust it is, it needs to stick to the wall not dust. There has been a lot of stripping and sanding in here. The walls need to be wiped off well.

The original paint job by the builder has been failing. It has started coming off down to bare drywall, on its own. No primer, cheap builders flat, sprayed on what were probably dusty walls is all I can guess.

Thanks.

Yea I hear this a lot about spraying over dusty walls, but I never bought into it. I have painted hundreds of homes this way and never had an adhesion issue arise. The thing is when you are spraying, there is so much air blowing around from the force of the paint being sprayed, it's pretty unlikely for dust to get trapped under there and anyway painting over a drywall seam or patch is just like painting over a compressed pile of dust. I think it's more likely the paint that is the problem, not the dust. The pinholes are there from applying the mud too heavily and are hard to see them all unless you paint first (the dust fills the holes).

You don't clean or wipe the walls before painting? This is way too dusty in here for that.

Undoubtedly the cheapest paint was used. There isn't any trace of primer. Just bare drywall is exposed. Kind of slick looking if you ask me. The original paint is 40 years old at this point. Some places started failing years back. I wish I could have just ripped it back to the studs and not have to deal with it.

I've read that rolling paint on works better at incorporating any dust into the finish than spraying over it. So that spraying over a dusty surface can have adhesion problems.

Really, a lot of times people can only speculate about what causes the problem. That's why it's good to follow the manufacturer's directions for the products, to reduce the likelihood of a fail.

I'm not saying I don't dust down the walls before painting. But, I did spray paint hundreds of homes that were not dusted down and never had problems or callbacks later on. I believe the reason for this is that the sprayer is its own duster...in other words, the force of the incoming spray blows away all the dust before it can be trapped under the paint. And yes, rolling is very important...we would always spray the paint on and backroll it. As for normal everyday sanding and painting, when I sand a patch on a wall, the dust falls to the ground because of gravity..hardly any dust is actually staying on the wall. What is left can be easily dusted away with a dustbrush or broom. If the drywall is slick, then that might not be drywall? Another option is to put drywall over the existing walls but for that you would need to remove baseboards and trim but this option isn't as messy as removing wallboards down to the studs.

We wipe down new drywall with a drywall sponge to both get the dust and settle down the paper fibers caused by sanding too vigorously.
Casey

Yes, I would prefer to double up and board over if it would work with the openings. Less mess and more insulation from noise and outside temperatures. Too late and probably cost prohibitive to hire out anyway. But that is the way to go if you can.

Thing is, Paintguy, is that if the builder had prepped properly and used good paint, these walls probably would not be doing this. They seemed fine for a couple decades. Now it's a bloody mess to contend with. It's definitely 1/2 inch wallboard.

This post was edited by snookums2 on Sun, May 19, 13 at 11:17

Getting back to the pinholes -
What I do is to vacuum, inspect for pinholes and mark the areas lightly with a pencil, cover the pinhole areas with another thin coat of compound, sand those areas, vacuum those areas, continue with painting.