How to get rid of lap marks?

timjones

Hi all,

My wife and I have been trying for days to paint a wall with chalkboard paint and it's proving to be a really frustrating affair. The first 2 coats went on fine enough with a roller, but then we notice lap marks so we got a wide foam brush and tried that and it made things so much worse. Then I tried a roller again and it improved a little, but it's still markedly worse than the 2nd coat, which was imperfect.

I'm a little worried that I'm putting too many coats on, but I don't see what other choice we have - the lap marks are really noticeable because this wall is right against a floor-to-ceiling window so the marks are really visible from the side. However, when looking head-on it's not that terribly noticeable.

I'd be grateful for any tips/suggestions on how to fix this once and for all please.

Thank you!

sdsester

With that chalkboard paint you have to put it on thicker than with a foam roller.

And you have to stir the solids in the paint container continuously. And then, you just have to let it dry and cure to see what you really have.

And please tell us you got this from a paint store and not a box store?

And why paint and not just a nicely hung and framed piece of chalkboard?

timjones

Hi sdsester, thanks for the reply.

We're using this paint which we got from a local hardware store (Home Hardware in Canada to be exact).

I've been finding that you can basically see what you'll end up with not long after putting the paint on. So if I see lap marks 10 minutes after painting they will remain there 4, 8, 24 hours after painting.

The wall we painted is relatively small and it's in the kitchen. We saw the look on the net and really liked it so we thought to take a chance. It'll look great if done properly, but it's just not coming out well because of the lap marks...

Anyway, we've done like 5 coats now. Surely there's a point where it's too much paint? What happens then? What options do we have at this point? Just keep putting the paint on? Try to touch up the lap marks specifically? Any ideas?

sdsester

That stuff is all about solid "pigment/stuff" left behind and with some binders to hold it together. I really think you should try getting some on the wall all at once with a thicker nap roller. I would go 3/4 but others might suggest even 3/8 to 1/2. You are not going to pull this off with a foam thing.

Like I said, stir the paint every time you glance at it.

If none of this works? As I said before, go to a stone store and order a real piece of "chalk board" and just hang it up in the space.

I have applied this sort of paint to kids rooms and so forth but can usually talk clients out of it. I suggest they hang a piece of white or black board up there and buy tons of markers to draw and leave notes with? Or there are the wallpapers designed to be drawn on with markers and so forth.

And why do you need a wall to ceiling chalkboard?

Finally, any time you have a textured wall or one with a high sheen coming at it and you view it side on from a light source like a window, you will spot every defect or lap mark. If this chalkboard wall looks alright staring straight at it? Maybe you are over working this situation? And, I think you still need to let the stuff cure!!!

timjones

Thank you sdsester, I appreciate the tips.

Would you say that I should be concerned about putting on too many coats? Is there a point where the drywall integrity is affected? We've put on about 5 now.

I'll try again with a new bucket as this one's nearly out.

You raise a good point about the fact that you will always be able to see every imperfection given that it's next to a window. I guess that's doubly more so given the fact that it's a black wall vs a white wall? Although it doesn't explain how the 3rd coat had significantly less lap marks then the 4th and 5th. I guess (bad) technique explains that one. Well, I'll let this sit for another 12-24 hours or more and see how it's looking then.

We don't _need_ wall to ceiling chalkboard, we just wanted it in our kitchen because we thought it'd look nice and be fun to have. I still think it'll look great if we can pull it off. :|

You say you've done this for some of your clients - was the final result completely solid black or did you find it difficult to avoid the lap marks? Not as a comment on your professionalism but just wondering if it's near impossible to get no marks given the paint and where the wall is...

I appreciate your help very much, thank you!

PS, on a site note, since this is a black paint and we have white elsewhere in our apt, how many coats of white are we likely to need to paint over this if we give up on it? Significantly more than normal?

sdsester

I don't remember applying the stuff and seeing noticeable lap marks. As mentioned though, it is a product heavy in pigment and solids if you don't stir it thoroughly and every time you glance at the can? The solids will settle to the bottom and you are likely to see the texture more in coats applied from bottom of the can sediments. I guess.

Never assume the paint store shaker has done its job completely. Always stir any paint.

Also make sure any finish, but especially these specialty types are within the expiration date suggested.

And I say again, you have to let paint cure before casting final judgment. Semi gloss latex products take 30 days, for example to mellow out and settle down to the final finish. What does the stuff you are using suggest the cure time, not the recoat time, to be?

I suppose black with light coming strong at it and viewed parallel to the surface would show more imperfections but I really think your problem comes mainly from the texture you are applying and not the color.

Your drywall will not fail from as many layers of paint you decide to put on it. The layers of paint may peel though. And please tell me you put a primer under this stuff? I actually think since you plan to write on this with chalk? A few extra layers of paint will work to your advantage.

As for covering it? Use a good, paint store superbonding primer to cover this if you abandon. You might put two coats on but I don't know that you will have to. Just be sure to use a thicker nap roller than I suspect you have been? 3/8 minimum for any wall and 1/2 better. I like 3/4 for semigloss but others disagree with me.

Two coats of nice finish over the dried primer of course and you should be back to all white.

If you like this look you are attempting and having gone so far with it? Why not give it one more shot making sure the paint is stirred, the expiration date is in range, and you have a thicker roller cover? Ask your paint store, not your box store person for their suggestions.