The Myth of Sole Flatness

I’ve never understood the obsession some people have over sole flatness. Somewhere along the way, a lot of folks got the impression that enough of the millions of vintage planes out in the wild are warped or distorted enough to warrant suspicion when buying. Worse, some even insist that for a vintage plane to be viable for use, it’s sole must be flattened.

Lie Nielsen states that their modern manufacture plane soles are ‘ground flat and square to .0015″ or better, regardless of length.’ Veritas planes have similar tolerances. Don’t get me wrong, I have nothing against either of these two companies. Heck, I own products from both of them. Certainly, if you’re spending $325 for a LN No. 5 Jack Plane made in 2020, you expect it to be dead flat. But is this a reasonable expectation in a plane that was made in 1920, and more important, is it even necessary?

In my opinion, sole flatness is a myth driven by modern day influences and perspective. We’ve been conditioned to believe that a couple hundredths or thousandths of an inch will somehow make or break the functional viability of the tool. But it’s silly to apply expectations of tolerances we get from computer driven milling equipment to mass produced hand tools made +/- 100 years ago. This is misguided at best, and completely unnecessary.

I suspect those who obsess over sole flatness fundamentally misunderstand how hand tools were originally used and likely have some pretty big misconceptions about 18th and 19th century furniture construction and finish. Hand planes were never intended to be precision instruments, at least not in the same way we think about precision instruments today. In today’s world, we tend to rely almost solely on the tolerance of our tools to produce precise results. 100 years ago, that was simply not the case.

Craftsmen and journeymen of the 18th, 19th, and early 20th century mastered the tools they had available and learned to compensate for any imperfections and limitations. Sure, some of them produced very precise pieces of furniture and cabinetry, but it was due to their skill and mastery, not the precision of their tools. And to be honest, most of the handmade furniture made during that period was anything but precise. Look closely inside and behind and underneath period pieces. The beauty and craftsmanship doesn’t lie in precision as we think of precision today. On the contrary, it lies in the subtle imperfections that reflect the hands of the maker and mark of his tools. That, in my opinion, is what makes it beautiful.

I’ve owned and restored many hundreds of vintage hand planes over the years dating from the 1870s to the 1980s. Some were in near mint condition, while others were closer to landfill fodder. Most fell somewhere in between, but the point is I’ve never seen one that was warped or cupped significantly enough that its usability was affected. All of them needed some degree of tuning and refining, but none required flattening. In fact, the only two planes I’ve ever “flattened” were two of my own block planes, and that wasn’t so much because they weren’t already flat, but because I wanted completely clean metal.

I’m frequently asked what kind of camera and lighting I use for my photos. I always respond that the secret to good photos doesn’t lie in better equipment or tools, but in mastering the equipment you have, learning to leverage its capabilities and overcome its limitations. Creativity isn’t stifled by constraint. On the contrary, constraints fuel creativity, innovation, and invention.

I think the same holds true for most other pursuits, as well. It’s certainly true for woodworking. Could I take even better photographs with a newer camera and broader selection of lenses? Sure. But that’s not the point. That’s not what makes me a better photographer, just as flatter plane soles won’t make me a better woodworker.

Don’t Strip or Dip! Scrape That Rust Away!

I read so many posts and articles online from guys doing absolutely heinous things to old tools. From chemical strippers to electrolysis, sanding to anti-rust dips, everyone has their own ideas about how best to remove rust. While any or all of these methods work, they’re all destructive on some level. I suppose that’s fine if your objective is to refinish the tool for use, but in my opinion it strips away all the character and beauty of the tool. Certainly some tools are so far gone there’s no other viable choice, but in many cases, there is a better way.

When I started collecting and restoring tools, I spent almost a year researching everything I could find on archival restoration and preservation, the techniques museums use. I didn’t want to simply refinish tools to make them appear new, I wanted to restore them to functional use while maintaining the aesthetic character that only decades of use and age can impart. My goal was (and remains) to bring them back to a point where they look and function as if they had been properly cared for over the years.

Like anyone else, my learning process came through trial and error. I quickly discovered that the anti-rust dips, while working well, left the metal with a dull and lifeless grey phosphate coating that I found unnatural and unappealing. Likewise, vinegar, citric acid, electrolysis, wire brushing, and sanding all do the job, but at the cost of all the color, character, and charm that makes old tools so appealing. What I really wanted to accomplish was to remove the rust while leaving (at least most of) the patina intact – that lovely brownish gray darkening of the metal that only comes from age and use.

Stanley no. 4C base, as found with considerable surface rust

I found that on many tools, specifically those that haven’t been exposed to overtly wet conditions, the rust is really only on the surface and in many cases hasn’t yet eaten into the metal, causing the cancerous pitting that we all despise. It has been my experience that often times a really gnarly looking rusty crust will come right off, leaving relatively undamaged metal that still retains that desirable patina below.

By using a 3 or 4 inch glass scraper with a very sharp blade, held at a fairly high angle, I slowly and carefully begin scraping the rust off the surface of the plane body. This does require a sharp undamaged blade. Once it gets knicks in the edge, it will start leaving light scratches in the underlying patina, which you don’t want.

It’s a slow and methodical process, but the payoff is worth the effort. As you can hopefully see in the photos above, there’s a distinct line where the rust is removed. You can also begin to see the underlying patina on the metal surface, and thankfully in this case, no pitting.

Scraping using the glass scraper

Once all the rust is removed, the metal surface will be dusty and dirty, and you may well see some micro-scratches from the scraper. I’ll take care of those in the next step.

Using a cleaner/degreaser, gently buff the surface with very fine steel wool (000 or 0000). You want to clean the metal, smoothing out and blending in any scratches in the patina without removing it. Careful here, as that patina is fragile. Go slow. Follow up with the cleaner/degreaser on a paper towel or rag until it’s completely clean.

Once clean and dry, I usually wipe it down with something to help protect and preserve it with Kramer’s Best Antique Improver. Howard’s Feed-n-Wax, Camellia oil, or Renaissance Wax, etc. will also work. Camellia oil, by the way, is really good stuff for protecting tools and knives, and is food safe. What you should be left with now is a clean surface free of rust, but retaining that beautiful patina.

The stanley plane body after cleaning, degreasing, and a wipe down with Kramer’s Best

With all the rust removed from the surface, you can see the underlying patina is still very much intact. Once the rest of the parts are cleaned and the plane reassembled, its beauty really shines through. I find this method of restoration produces superior results to any other I’ve found thus far. Mind you, it’s a workout! But that’s okay, too.

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