Corrugations: Stopping Stiction? Or For Suckers?
Handplanes with corrugated soles vex many woodworkers. If you find them on a vintage plane, should you grab it or should you shun it? If you order a bench plane from Lie-Nielsen Toolworks, should you spend the extra $35 to get a corrugated sole or is that money better spent on some Lehman Brothers stock?
Corrugated soles started showing up on planes in the late 19th century. Craftsmen noticed that their newfangled metal planes were harder to push than their old-fashioned wooden-bodied planes, according to period accounts and patent papers.
So manufacturers began to mill corrugations in the soles of their planes. For a peek at their reasoning, check out this 1869 patent by E.G. Storke:
“…¦(E)xcessive friction was caused by their exact and even faces (of their soles), which were not materially varied by use or atmospheric changes.
“When used on very level surfaces, there were so many points of contact that the friction was troublesome, and the adhesion was further increased by atmospheric pressure, as partial vacuums would thus be formed.”
In other words, the planes were sticking to the work when the boards became really flat. I’ve encountered this when working with closed-grain woods, especially poplar and maple. In fact, if the board isn’t too large, I can occasionally lift the board off the bench because it is stuck to the tool’s sole. It’s a neat trick.
But is the plane harder to push if it doesn’t have corrugations? Many pointy heads I’ve talked to about this are dubious. Friction, they explain, is a function of force , not the surface area of the sole.
I have planes with both smooth soles and corrugated ones, and if there is a difference in effort required to wield them, I cannot discern it.
But there are some practical differences you should be aware of:
1. Corrugated soles on vintage planes are easier to flatten because there is less metal to remove. So if you have an old sole that needs work, corrugations are a plus.
2. The corrugations hold paraffin or wax. This wax wears away completely during use, so I assume it is lubricating the sole.
3. Corrugations on some sizes of vintage tools are rare. So if you are a collector, keep an eye out for them.
So here’s my bottom line: Corrugations don’t change the function of the plane for better or for worse, so it doesn’t really matter either way. I wouldn’t spend extra money to have them added, but I wouldn’t kick them out of bed for eating crackers, either.