[DIherself]

There's only one coat of cured latex over one coat of lead in patches on the shady side of my garage. (see pic with white emphasized patches) I just hit the patches with 16-grit sandpaper, sprayed first with cooking oil, at 4500 rpm with my disc sander. The latex barely budged.

I did the sunny wall of the garage last year and did not have this stubborn latex problem. I'm going to have to get the latex off first with something, but what? I'd like to use a natural paint remover, like a solution of ammonia, borax, washing soda and water, but it'll just drip off and the instructions say to let it penetrate the paint for 30 minutes.

I don't want to use a heat gun. Has anyone ever used denatured alcohol? Anything else? Luckily, I have all summer to finish the wall.

Thank you from Florida.

 

[joecaption]

Why would you spray it with veg. oil?
That can keep the new paint from sticking when you grind it into the wood.
Paint that old is very likely lead based paint so use precautions.
There's lots of safe strippers avalible, google it.
Citrics based.
Soy.
Peel Away.

 

[DIherself]

No, I'm grinding the oiled sandpaper into paint, not wood, leaving a leftover film of paint that is then sanded with oil-free sandpaper -- down to bare wood to soak up a penetrating oil.

I was wondering if anyone had a good result removing cured latex with denatured alcohol or ammonia/borax/soda or something else. I found suggestions to use those two natural mixtures on Google, but no one that actually used it to testify.

 

[ToolSeeker]

What in the world is the purpose of oiled sandpaper?

 

[DIherself]

The purpose is for lubrication, to help prevent loading the sandpaper with paint when the sander heats it up. You spray a little Pam cooking spray on the sanding disk. I've read that you can also use high-temperature barbecue grill cooking spray, but I haven't tried that.

When I sanded the paint off the front of the house with a Porter Cable paint remover, I sprayed it on the carbide diamond (whatever) discs and it worked great. When I sanded the paint off one wall of my garage using aluminum oxide disks (because I sold my Porter Cable, darn it), I sprayed it on the aluminum oxide sanding disks and it worked great.

 

[mathmonger]

Are you making laundry detergent or stripping paint?

What about lye? That might have a shot at working.

And you probably are contaminating all your soil and air with lead.

 

[DIherself]

I have drop cloths down and up against the garage, and I have raked about a two-foot-thick layer of leaves, which I wet, and load them up against the garage. At the end of the day, I fold up the drop cloth, containing the leaves, and empty that into a large plastic bag, which I tie tight --or tightly -- and then it is ready for disposal in the regular garbage. I researched that.

There's question as to whether lead was/is even in latex paint, and the lead may only have been used in white pigment or as a drying agent; when you bought a gallon of "lead-containing" paint years ago, it doesn't mean you bought a whole gallon of liquid lead.

I don't really know for sure what kind of paint those two layers are, but I'm treating them as if they contain lead so I can get on with the project. I think the first layer might be, but who knows what has happened to the composition of that first layer with a layer of who-knows-what painted on top of it that has been exposed to the elements for 75 years. Any studies on that?

If those substances are used as laundry detergent, they must be pretty powerful to cut grease, grime, perspiration, dirt, blood, wine, vomit and lipstick.

 

[ToolSeeker]

I must say I have never heard of using cooking oil to lube sandpaper. Since your outside use a mask and try using sandpaper the way most people use it. You may find that's all you need.

 

[Will22]

Denatured alcohol would only soften latex paint- it will not do anything otherwise. You should have someone check the lead level before proceeding.

 

[DIherself]

I always try the normal way until something goes terribly wrong. I'd never heard of lubing sandpaper either until my expensive Porter Cable paint remover's diamond carbide disk loaded up after the first two minutes on the job. Then I googled what to do, and that's when I found out about lubing with Pam. I did have to take a wire brush and clean the disk every so often and re-spray, but it worked.

I also sprayed Pam on my aluminum oxide sandpaper or fibre resin (can't remember if I used one or both) last year for that one wall and got all the paint off, except for a thick stripe and a thin stripe that would not come off even with 16-grit sandpaper, so I left it. See picture of designer stripes.

I read that latex paint gets really really hard after a while, and that's what makes me think the top layer on the splotched wall in question is latex. The top thick stripe in the pic is shaded, and the thin stripe is shaded between the clapboards. The paint patches I can't get off is on the shady side of the garage. So the shade may have contributed to this pig-headed white paint that I'm stuck with.

Maybe I could soften the latex with denatured alcohol, let it dry, and it would be easier to sand off? I'm treating the paint as though it is lead. Thanks both.

BTW, check out Sparky Abrasives. That's where I got my sandpaper, and I couldn't believe the variety. Some of the paper is heat resistant and self-lubricating but that might not be for wood.

 

[PRP]

We have always found oil-based to get harder than latex and LBP being the hardest to remove by sanding.
On lead projects my preference is to use chemical remover, Fiberlock being the preferred brand. I like their Nexstrip Pro for a dwell type remover and Piranha 4 for faster acting. They'll run you about $300/5 gal. which may seem spendy but consider the benefits. Apply a thick coat, cover with poly and come back hours later to easily scrape softened paint off with no dust and only a little elbow grease. Repeat until removed. There are plenty of other removers available by Dumond and others.

Also lead pigments came in white, yellow and red. With a can of paint containing up to 70% lead by volume.

Glad to hear you are collecting the waste, although Id suggest attach 6 mil poly to the lowest board with a baton strip. Makes fpr easy clean up and also......Wear a mask!

We do alot of old homes and historic restoration work. It can be hard work so make it easier and use remover. The ones I mentioned are low toxicity. Happy scraping!