Popular Woodworking 2003-06 № 134, страница 18

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What's the Best Finishing Procedure for a Kitchen Floor?

In a recent issue, you wrote that after letting an oil finish cure for about a week, you could go ahead and put on a film finish. I am considering adding a wooden floor to my kitchen, and I'm hoping to get your opinion on the chemistry and the likely long-term success of my efforts.

After removing the vinyl floor and adding the wooden flooring, I'll apply a coat of tung oil mixed with spar varnish to get a color I'm comfortable with.

Then I plan to add several layers of water-base polyurethane on top. Any compatibility or long-term wear issues with my plan?

John Zachman Eden Prairie, Minnesota

Forgive me, but I've got to wonder why you're doing what you're doing. You're talking about a kitchen floor that takes a beating. Why wouldn't you just put on three coats of oil-based polyurethane, which is the most durable finish you have available to you for that type of application, and be done with it? I would think that the coloring would be very similar.

Oil-based polyurethane is going to wear a lot better than water-based polyurethane.

There are two good reasons to substitute water-based polyurethane for oil-based on a floor:

1. You are trying to avoid any yellowing.

2. You want to avoid the odor of oil-based polyurethane.

Clearly, you're not trying to achieve either. You're putting "yellowing" into your floor with the tung oil/varnish mix, and you're getting the odor (for awhile, at least) from that same finish.

To answer your question: Yes, you can apply water-based finish over the tung oil/varnish mix. But you've chosen the worst possible oil and the worst possible varnish for curing qualities. They cure extremely slowly, and you have to let them cure totally before you can be sure of a good bond (I am assuming you're using real tung oil, not wiping varnish). I'd give the floor several weeks, at least, in a warm room.

But what are you going to do with the floor while you're waiting for that oil/varnish mix to cure? You shouldn't use it at all for at least three days because of the tung oil, and then you're going to have to be very careful not to spill any oily or greasy substance on it. A rule for coating over another finish is that it be perfectly clean -

16 Popular Woodworking June 2003

not usually a problem (except for dust) in a shop. But who knows what you might be tracking in on your shoes during those weeks.

I'd use oil-based polyurethane.

— Bob Flexner, contributing editor

Is Cryo a Crock or for Real?

In the December 2001 article on cryogeni-cally treating blades and bits ("Why You Should Freeze Your Tools") you said there would be a follow up on the tools that you had treated. Do you have any results yet?

The reason all this comes up is that recently, after not realizing how long it had been since the iron on the plane I was using saw a sharpening stone and thus gouging a project with a dull plane iron, I looked at the irons that came with my planes. Some were pitted beyond good taste, and I ordered Hock replacements (hocktools.com).

I also spent the extra cash for the cryo-treated A2 Hock irons. So I am curious to learn what you have found with the tools you sent for treatment. Even if the cryo treatment makes the irons worse, give it to me straight, without regard to the money already spent; after all, that is what I count on Popular Woodworking for.

Paul R. Bruzinski Albany, New York

I've been using the items we had treated to see if there's a difference. My unscientific conclusion is that it has helped some items and not others. The high-quality tooling (that was probably heat-treated really well at the factory) hasn't shown much difference. But the low-quality stuff (like some cheap chisels) now wear longer.

The other factor to consider with irons for hand planes is that some say A2 won't take the keen edge that O1 (high-carbon steel) will. I can't tell any difference. I can get A2 as sharp for woodworking. Maybe there's a difference at the microscopic level, but not that I can tell.

Bottom line? Keep your A2 cryo stuff. A good cryo lab will correct any heat-treating problems during manufacturing and ensure your blades are as durable as they can be. Should you buy all cryo stuff? It doesn't hurt (the up-charge is minor), but the No. 1 consideration with edge tools is always buy the best quality you can afford, regardless if it's A2, O1 or something more exotic. PW

— Christopher Schwarz, senior editor