Re-Surfacing Old Painted Boards
It may not be worth the risk of exposing your planer to damage. But there are other ways. January 27, 2007
Does anyone have experience thickness planing old painted pine floor boards? I'm wondering how the planer knives might react to the paint. Should I expect dull knives? I don't have a huge amount to plane, only about a dozen or so boards ranging in width from 6-8 inches.
(Solid Wood Machining Forum)
From Dave Rankin, forum technical advisor:
I have surfaced quite a bit of painted wood. Some things to consider:
1. A lot of old paint contains lead and the fumes and shavings need to be handled with this in mind.
2. The paint that I have surfaced dulled my knives in a matter of just a few boards.
3. The quality of the wood, after being surfaced, varied from excellent to junk.
4. It can create severe wear on the table of the machine and/or the feed rollers.
I have made the decision not to surface painted stock for anyone else due to the expense and feed problems that I experienced.
From contributor R:
Just run them through. The paint isn't going to be much of a problem with 6 boards. I'd be more concerned about the boards if they were painted before 1978, when they banned lead paint, so don't breathe the dust. Any grit embedded in the floor is going to dull the knives more. We do antique lumber in our shop. You haven't seen nothing yet when it comes to tough wood to mill.
From contributor L:
Not a chance painted boards would go through my planer! Buy new boards or trash your knives, maybe hit a broken off nail that gets pushed down and gouges the planer bed. Not worth it!
From contributor C:
Take heed to all this advice. You will give the machine table several scratches and you will likely throw the knives away or at least have to get them resharpened (if you're lucky). Are the old boards worth it? The labor to change the knives is a good half hour.
From contributor F:
Good point about nails being driven downwards and scratching the planer bed. This is easily avoided with an auxiliary bed board clamped to the planer's bed and will also protect the bed from wear by a painted surface. Dull knives can be sharpened.
From contributor D:
I've have been recycling old wood for thirty years. I have used two entire old water towers from Chicago made from redwood. This old growth clear redwood is well worth the effort. I went through a lot of respirators and planer knives before I came upon the method I currently use. I grind all of the paint off with the Paint Shaver tool hooked up to a dust collector. It works very quickly. I use an electronic wand to find all nails. It works great.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor A:
I recycle old wood all the time. Our front porch was made from an old redwood water tower taken down in Chicago. All old paint is going to be lead based and it dulls planer knives very quickly. Plus the paint will hide nails. I take all the paint off before surfacing.
I use a Paintshaver with dust collection to grind the paint off. If you do not have a dust collector hooked to it, wet the paint so it does not create a lot of dust. I then use an electronic wand to check for nails before surfacing. We should all try to recycle as much old wood as we can. It is a lot of work, but very satisfying.