Restore a Folding Rule

I feel like a dirty English tool dealer this morning. But I’m OK with that.

Recently I purchased a bunch of brass-bound folding rules to give to co-workers and friends. Most of these were Stanley No. 62s, a common rule that I really like. If you want to know my favorite one, however, you’ll have to come to Cincinnati in May and fish it out of my tool cabinet.

In any case, the last folding rule I had left to give away was definitely an Alberto Fujimori (a former ruler). The scales on the outside were too dark to read. The scales on the inside of the rule were OK. The rule had cost only $1.76, so I wasn’t feeling overly shafted.

This folding rule was special because it had been used hard. The brass corners were worn from frequent use. One of the scales was charred a bit (that must have an interesting tale behind it). But despite the bad scales, its joints worked well and the rule had two of its three alignment pins intact , so it hadn’t been mistreated. Most folding rules are missing these pins, which keep all the components locked together when the rule is folded.

So I decided to try to restore this rule and see if I could turn it back into a nice piece of workshop equipment. British tool dealers have a bad reputation of taking beautifully patinated tools and wire brushing them into pupil-piercing brilliantness. I didn’t want to do that. So I started with a mild cleaning with mineral spirits and a toothbrush.

That did absolutely nothing.

So I consulted Philip E. Stanley’s book on folding rules (“A Source Book for Rule Collectors” , love the book, by the by). He recommends using Boraxo, a hand cleaner with lanolin. You can get it at home centers. It’s a bit gritty, smells like oranges and removes grease from your hands.

Here’s the ruler after I treated one scale with Boraxo (at top). The other scale is untreated.

I cleaned one arm of the folding rule with the stuff last night and things began looking up. The paper towel got a brown skid-mark and the ruler got easier to read. However, Easter morning I woke up and (after making French toast and helping the kids find their eggs) I decided to do a little ruler resurrection. I was going to potentially throw my $1.76 down the metaphorical toilet.

I mixed up some wood bleach (oxalic acid). I like a solution of three tablespoons of powdered bleach with 16 ounces of hot water in a glass salsa jar. I use this bleach solution for removing iron stains when I steam-bend wood and then nail it (like when I make Shaker oval boxes).

Here’s the ruler after I treated one scale with oxalic acid (at left). The right scale is untreated.

With rubber gloves on, I applied the bleach with a woven gray pad. Within a minute, the boxwood lightened considerably. But the ink on the rule stayed intact. Whew. I rinsed the rule in running water, allowed it to dry and applied two coats of wax.

Sorry tool collectors. You’re going to have to wait for another 50 years of patina before you can have this one. It’s going back to work.

– Christopher Schwarz

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