best tool for paint cleanup rough claps for repainting?

[Ken Platt]

Folks - I am repainting my home's exterior and was looking for any wisdom on how to cleanup - after washing - the loose paint on the clapboards, which are rough side out. My carbide scraper seems to damage the wood, and isn't getting the slightly loose paint off. It's an older home, so in addition to being rough side out, some of the claps are a bit concave. Hard straight blades don't seem to be my friend here.

Compressed air seems to do better than the scraper, but hard to do on a medium amount of rough areas. Angle grinder with nylon flap disc does better still, but a bit too aggressive. I don't need all the paint removed, just the stuff that isn't well stuck on.

Anyone with some tips/recommendations on this? I have grinders aplenty, and also a 5" hood and loop right angle sander (older PC brand). Much appreciated.

Ken in Granby, CT

[Ron Selzer]

I have seen a couple of houses commercial sandblasted and then painted in the town I grew up in. First one (two story house) about 30+- years ago it just now needs repainted with very little touchup needed first.
I grew up scraping and painting a two story house every so many summers, one of many chores to keep me out of trouble.
Ron

[Brian Runau]

I painted my garage door after taking caulk on a wet sponge and going over all the rough edges first after sanding. Helps keep future peeling down. I think they make a paint formulated to do this. Brian

[Bill Howatt]

Don't know if this will be of help but I just finished doing about half my cedar house that had Sikkens translucent Cetol 1, 23+ on it. Where the Sikkens had not been exposed to direct sun it was well adhered. I used a ROS with 40 or 60 grit disks.

[Tom M King]

We never put paint over paint that has even started peeling. It all has to come off. Heat guns to bubble it up, and try a number of different things to pull it off. We use supplied air. Good paint will last decades these days, but not over something under it that will release.

I tried some SW Rain Refresh Emerald when it first came out, and that's all I'll be using until they come out with something better. I put it on a fascia on the rental house that normally gets black streaks in a few months, and this still looks like I put it on yesterday.

This is 1850 siding. It's not rough but there is a lot of aging texture on it. I have a bunch of different texture wire wheels to go on a 4-1/2" grinder. You have to try different ones, but there are some that are soft enough not to take the wood texture off. This whole house was done like this. It took two helpers a whole Summer, but they were using an air conditioner to supply air to their hoods and Tyvek suits.

Even on small jobs all the old paint comes off. See current thread about heat guns, and the long paint scraper thread in the Finishing forum. Yes, it takes a lot of time, but not likely to need being redone for decades.

[Ken Platt]

Thanks folks. Tom, thanks for the heat gun recommendation. I bought one. Besides the house painting, we have a brick wall painted white inside out house, and my wife would like it unpainted. Stripper didn't do anything, so I figured heat, few square feet at a time.

Ken in Granby, CT

[Tom M King]

If it’s wire brush textured brick, I wouldn’t bother to hope you can ever get it all off.

[Tom M King]

Do what you need to for lung protection. If you can smell anything, whatever you are using is not stopping it all.

[Bill George]

I am under the impression if its on so tight you can't get it off without a lot of effect then leave it on and paint over. Brick unless its smooth, sandblasting is the only way.

[Ken Platt]

I'd figured that no matter what, I was going to end up at best with a sort of motley white and brick appearance. If it's not an improvement, I'll give it up. I figure I can use a good heat gun, so nothing lost in a try. I planned to open windows, and put a big fan on one side to draw air through the room and out. So it's sort of an experiment - if it works, I'll post before and after pix. If it fails, I'll keep it to myself....

[Tom M King]

I wouldn't think of trying it with no better breathing protection than that. All sorts of fumes come off from the melted paint. Test it for lead. Supposedly they stopped putting lead in paint in the 1970's, but someone may have used old paint. Lead tests are cheap. Even if there is no lead in it, no one should get any of those fumes in their lungs. I would bet the first coats on that brick, and maybe even top coats, are oil based paint. It takes a Lot of paint to cover brick, so there has to be a lot on there.

I only ever use a heat gun with supplied fresh air.

I've never done paint off brick, but we did get old whitewash off stone basement walls in an 1828 house. We kept a pressure washer running for a week. There are still little bits of whitewash left in mortar crevasses here and there. Whitewash was just salt and lime mixed together.

[Ken Platt]

I appreciate the advice. Guess I'll rethink it. I don't have any sort of breathing apparatus beyond a good quality mask.

[Kris Cook]

Ken - supplied-air is great if you have access, particularly working in the heat but not absolutely necessary. Look into organic vapor cartridges for an APR or PAPR respirator (North, MSA, 3M all good brands). Ideally, you would get yourself fit tested, also you need to be clean-shaven. Like Tom said, if you can smell anything, your protection isn't working.