Good day to all.
As I stated, I am truly stunned by an innocent error and am hoping to have some light shed on some possibilities PLEASE…
I apparently did something ignorant…okay, stupid. Beautiful new drywall surfaces, and in “haste” found some remnant paint in excellent condition. Thinned it, and then rolled away onto the raw surfaces of the drywall and joint compound, with the intent to prime of course…
It was, it turned out, 100% acrylic exterior paint. I thinned it almost 50%.
After drying, and the test with the thumbnail reveals less than stellar adhesion to the joint compound areas, (horrible really)and it is fine on the drywall paper itself. With not much effort at all, I can peel off the paint film…oh my.
I cannot bear to think of stripping the film off of new walls just finished previously….I am ill thinking about it.
Is there any recourse? Should I actually proceed and put MORE paint on the walls?
Oh please help!
Hunts319
Replies
Bad news, I'm afraid. I don't think anything you put on top of what's already there will increase bond strength.
Everything will be okay in the end. If it's not okay, it's not the end.
drywall
Well, yeah, there's that...
Everything will be okay in the end. If it's not okay, it's not the end.
I would go over the whole thing, lightly, with a pole sander.
They prime with a something "better" than a basic drywall primer. Something like BM Fresh Start or SW Prep Rite.
William the Geezer, the sequel to Billy the Kid - Shoe
exactly what bill said. Go over the compound again with a sander to get the paint off.
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Calm down and let it dry. I bet it will better later, The paint ALWAYS dries first on the paper.
First like Dam Inspector (who doesn't inspect dams) said, calm down, have a beer, give it some more time - it might get better.
Second what BillH and Andy said - light sand and prime with a quality primer then let that dry.
Contrary to popular belief, Fresh Start's (do not thin!) drying time is 3 hours (minimum) before recoating -- read the can if you don't believe me. I know it is dry to the touch seemingly in seconds especially if you are painting a raised panel door........
The only thing I hate more than painting is repainting because I screwed up -- that's why I read and follow manufacturers directions to the "T".
Anything that you apply on top of the now-loose film will not improve the film's bond ---- it will just make the situation worse.
Good luck.
Jim
Edited 9/8/2009 7:50 pm ET by JTC1
From someone who actually worked with paints and their chemistry in a previous life: Dry to the touch and "cured" paint films are two different matters. Paint at room temperature will take AT LEAST 24-48 hours to develop significant film strength.
(Don't believe me? Paint something on, say, metal. Do the thumbnail test at intervals. It can take weeks for paint to reach maximum strength.)
So, relax and have your beer. You cannot hurt anything by waiting. And, it gives you a reason not to do everything right away.
DISCLAIMER: I did not work with house paints. It is my understanding that there are some things to prevent mildew in them; you might want to call the paint mfr and ask if the paint can be used indoors.
I agree. Recently I painted some metal with the wrong paint. I was amazed at how soft the paint was and how easily it peeled off.
By the time I got arround to stripping it off (it really was the wrong paint for the application) it was hard and hard to get off.
I just re-painted the metal with the right paint and guess what. It is soft and peeled off in a few places where I handled it.
Paints always amaze me the way they act. It seems like every time I paint something else is different!
No, I'm not re-painting it again!"There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."Will Rogers
I suspect that thinning it as much as you did is the cause of the problem. Water will soften joint compound and make it lose its adhesion. But that's bad news/not so bad news. The bad news is that it may never adhere (but it's still worth waiting like others suggested). The not so bad news is that it should sand off pretty easily. You may need one more topcoat after sanding to smooth things out.
By the way, if you ever wet sand joint compound, be sure not to get the compound too wet because that can also cause the problem you're seeing. By "not too wet" I mean the compound should always be pretty much dry to the touch.
Water based paint resins require a high pH value (usually 8 to 8.5) to form a proper film. Lower the pH too much and the resin molecules will fall out of suspension.
By thinning 50%, you greatly lowered the pH (to 7.5 or so), perhaps enough to kick out the resin. If so, it will never form a film and anything you put over it will have poor adhesion because of a layer of failed goo between it and the substrate.
The "adhesion" that you are seeing to the paper is just material that soaked in.
I would call the paint manufacturer and talk to a chemist (not one of the customer service dopes who only read from a script) to see whether the resin can survive such a drastic dilution and what you can use to remove it if it is ruined.
Good luck
For future reference, there are two basic types of water paints; water based emulsions (latex, acrylic, water based "lacquers") and water borne alkyds. The alkyds can be reduced 20% to 30% with water without harm. The emulsions are meant to be used out of the can and will tolerate about 5% dilution with water. To reduce 10% or more (say for spraying out of a cup gun) you can use 50/50 water alcohol blend with 4 ounces per pint of household ammonia added to keep the pH up.
BruceT
Edited 9/8/2009 10:02 pm by brucet9
Edited 9/8/2009 10:13 pm by brucet9
4 ounces per pint of household ammonia added to keep the pH up.
BruceT
Now THAT is something I did not know.
Follow on question - how come frozen latex paint smells like ammonia???? (I know, throw it out)
Triethylamine is what you are smelling.
Commonly used in very small amounts in water latex and acrlyic paints.
There are a variety of amines - ethanolamine, diethylamine, triethylamine and others- that have evaporation rates similar to water, so the pH will remain stable for a long time in storage even when the can is only partially full. When the resin is ruined by freeze-thaw cycles (many resins can take a couple of cycles), these chemicals separate out and their ammonia-like odor becomes more noticeable.Ammonia evaporates fast, so to facilitate heavy reduction it works best when you use a lot of ethanol or isopropanol, which also evaporate fast.The benefit is that you can lower viscosity enough to atomize into small particles in a cup gun or cheapie HVLP gun. Most of the alcohol and ammonia will evaporate in the air and take some of the water with them, leaving even tinier droplets of full bodied paint on the work and that helps to keep it from sagging.BruceT
i'd give it a couple days ,see what happens.
if it still isn't stuck i would rent a pc drywall sander and about 100 grit and sand it good.
your the first person here on bt to ever screw up,the rest of us are perfect.
the older i get ,
the more people tick me off
Thank you all for the time taken in replies. I am less stunned now that some time has passed, haha, but the adhesion has gotten only a touch (pardon the expression) better.
PC drywall sander ??
Hunts
Porter Cable drywall sander.
Alwaysoverbudget may be nicknamed Alwaysoverkill in this case, but I don't know how much sanding you need to do.
Now that I'm thinking about your issue again, I have a thought. If the paint that you applied was thinned enough so that its actually porous, a coat of oil-based primer may soak right through the paint and re-adhere everything. I've done it with old paper wallpaper and it does work... to a degree.
I would definitely experiment first in an inconspicuous area because if it doesn't work well, it will certainly work well enough to make that spot harder to fix.
i'm not really sure how much area he has here. i kind of assumed more than one room??
so just call me alwayslazy. if i had to go in and sand this i would try and get 90% off the mudded areas,that could be alot of sanding,especially if it's overhead.
if you think just a quick swipe with sandpaper,it would be overkill.
the older i get ,
the more people tick me off
Hard to picture how bad it is.But my though is that is only needs light touch sanding and not complete removal..
William the Geezer, the sequel to Billy the Kid - Shoe
If you use the power drywall sander you have to be careful. It is very easy to oversand the paper part of the drywall causing a rough surface that can be difficult to remedy.
Not that it will change the solutions, but in your haste, did you remove the sanding dust? A layer of dust will screw with adhesion as well as anything else.
If you want to see if you can get away with not sanding it all off, go away for a week or two before checking the adhesion again. Paints really do take quite a while to cure.
Yes I did, but good call on it anyway, I thoroughly broomed the walls to get as much off as I could.
Hunts
Depending on the client and the amount of trim involved... my first choice would be to rock over with 1/4" DW, it's light, and you can run the sheets vertically (quick to tape). Of course, higher than 8' ceilings will have butts (I've only seen 1/4" 4x8's)
I have visions of getting a call every change of season that the paint is peeling somewhere. If there are kids in the house all the worse...
If you sand, I would put a coat of SW "Drywall Conditioner" on after sanding/wiping the surfaces.
Thanks for sharing...
ps a little tip- write the month/year and type of paint on the lid. If you don't use it in 3 months, toss it.
good luck,
Jim
The awful thing is that beauty is mysterious as well as terrible. God and the devil are fighting there, and the battlefield is the heart of man.
- Fyodor Dostoyevski
So let us know what works for you....this is a mistake that anyone could EASILY make, and we might as well learn.
Thanks,
Scott.
So far I have been watching (reading) and waiting. I definitely screwed myself doubly by thinning it: The areas where I happened to cut in with a brush from what was left in the bottom of the unthinned original [strength] can are much harder to fingernail off as a test. But there just isn't much of a bond anywhere there was broad areas of compound, such as corners. In those areas I can get the paint film to pucker right off by using the maskingtape test.
I have taken my PC random orbit handheld and sanded some of these tested areas and the paint does come off in small shards, curls etc. But the effort required to do this is increasing as days pass.
I was wondering, (and will test this this evening) what would happen if I bought a can of shellac-based primer and tried that; I am hoping, and maybe dreaming, that the alcohol inthe primer will possibly melt its way through the thin film and get to the substrate somehow.
As you can tell I still would like to avoid sanding. Its three rooms, no ceilings, and an archway that was skim-coated. That would be fun (not).
Hunts
I just used shellac primer for the first time over areas where the glue from wallpaper was making it impossible to paint.
everytime even sheetrock mud would roll up onit.
So I tried the sheallac and it would bubble up for about 30 minutes while drying then pull back flat.
After drying it was real easy for my sheetrock guy to put a skim coat on then we sanded primed and painted again.
I have really gotten tired of removing wallpaper to go back to painted walls no fun and a lot of extra work for everybody.
ANDYSZ2WHY DO I HAVE TO EXPLAIN TO FRIENDS AND FAMILY THAT BEING A SOLE PROPRIETOR IS A REAL JOB?
REMODELER/PUNCHOUT SPECIALIST
FWIW - I don't see professional painters thinning latex paint....