Our ancestor's sharpening technique

[David Christopher]

I do know that I see alot of people running their plane back and forth. when I was younger my grandpa would fired you on the spot if you slid a plane backwards.. you had better pick it up on the back stroke and cut on the front stroke....he would not you use his chisels, plane or handsaws. and it seemed like they stayed sharp all the time and I dont remember him sharpening them very often ( maybe better steel ) I dont know

[Larry Williams]

Well for one thing, Leonard Lee hadn't come along yet to show therm what that edge really looked like under magnification.

Are you aware that Van Leeuwenhoek was examining cutting edges at 200X in the 1600's and writing about it? Do you know he replied to the British Royal Society when asked about it and talked about the abrasives he used to get the best edges? I think you'd be familiar with those he mentioned. Hmmm, come to think about it have you considered what abrasives and what accuracy would be necessary to grind the lenses for the microscopes he made? I really wish there was a way to eliminate the notion so many have about how primitive people were in the 17th, 18th and 19th Centuries.

[Robert Rozaieski]

I really wish there was a way to eliminate the notion so many have about how primitive people were in the 17th, 18th and 19th Centuries.

Larry,
I don't think it's so much a notion that they were primitive, which they were obviously not considering they developed some of the very first vaccines in the 18th century. However, what was typical, affordable and readily available was different. Sure, they probably had the abrasives we have today (silicon carbide is basically a form of sand) but they hadn't the technology to turn it into a man made stone very easily or inexpensively. Plus, they didn't need a man made stone. The natural ones worked just fine. They would also be much cheaper than a man made stone (totally opposite today however). But mostly, they were simply interested in getting an edge that was good enough and getting back to work.

As a scientist they may have been interested in the microscopy of the edge but as a cabinetmaker they could care less. They knew how to sharpen "good enough" quickly and get back to work because cabinetmaking put food on the table not sharpening to the nth degree. Natural stones were readily available and they got the job done so that's what they used.

I think there is a huge difference today in that so much more is readily available to us in the form of product and information. So much so that we take things like sharpening to an unnecessarily complex level simply because we can afford to. Most of us don't rely on building furniture to pay the bills but rather we do it as a hobby. If our ancestors knew how long some of us took to hone an edge or build a piece of furniture they'd probably have a heart attack.

I think the main difference between how they honed in the 18th and 19th centuries and today was priorities, not necessarily technology. Our ancestors honed so they could get back to work and pay the bills. We hone to see how many hairs we can scare off of our arms before the edge actually reaches them. I think it's kind of like the fussing over how thin of a shaving one can get from their plane and measuring it with a micrometer. It's a trivial activity with basically no actual usefullness in working with wood but it's what gives a lot of folks enjoyment when they aren't doing their day job. Who am I to argue with what someone else does with their free time. Me, I like to build stuff so "good enough" is good enough for me .

Now to get those darn doors done !

[Jim Nardi]

Any well used tools that I have bought are in good shape and very well tuned. My favourite planes to seek out on e-bay have short blades. I've always suspected long chisels and full blades in planes to have never seen a craftsman's hands.

[Joel Goodman]

I have the same suspicion of old planes with full blades -- it seems that in the last 75 years or whatever if the plane was good someone would have used up a lot of the blade.

[Mike Henderson]

I've bought planes that we know are good - that have a high reputation today - and had short blades, or replaced blades. None of those had the back flattened, or the back edge polished (such as with a microbevel). Maybe those planes went from professional use to abuse but you'd think I would have run into one that was sharpened well (by today's standards).

Additionally, no one has yet reported (in this thread) that they bought an old plane with a flattened back on the iron (that hadn't been done in modern times).

I think our ancestors just sharpened differently than we do (as suggested by several posters).

Mike

[Jim Koepke]

I've bought planes that we know are good - that have a high reputation today - and had short blades, or replaced blades. None of those had the back flattened, or the back edge polished (such as with a microbevel). Maybe those planes went from professional use to abuse but you'd think I would have run into one that was sharpened well (by today's standards).

Additionally, no one has yet reported (in this thread) that they bought an old plane with a flattened back on the iron (that hadn't been done in modern times).

I think our ancestors just sharpened differently than we do (as suggested by several posters).

Mike

All but a few of my planes were bought used. Some of the blades looked like they were butchered. The blade would still cut wood, just not as well as I would like. Some of my planes were from a retired cabinet maker. The blades were sharp and an original type 10, but not worn down. I have seen a blade taken down incredibly fast by someone who thought they knew how to sharpen on a grinder. They would have likely done better by trying to beat an edge on it with a hammer.

Some of my used planes did have blades with the backs showing evidence of flattening or maybe someone's attempt to remove pitting.

I have also noticed a blade can be pretty dull or in bad shape and still cut wood. For trimming the edge of a door, this is likely good enough. For leaving a glassy surface on the face of a board, it isn't.

If a blade is sharpened regularly with care by someone who knows what they are doing, I think it would take a long time to wear it down to replacement time.

Just my opinion,

jim

[Jim Koepke]

I've bought planes that we know are good - that have a high reputation today - and had short blades, or replaced blades. None of those had the back flattened, or the back edge polished (such as with a microbevel). Maybe those planes went from professional use to abuse but you'd think I would have run into one that was sharpened well (by today's standards).

Just another thought on this. When an edge is established, there is the burr or wire edge that is typically taken down by flipping the blade and dragging it on the stone or by honing. The micro area that was polished by this would likely be as effective as flattening the whole back.

Some of my chisels have shown signs of honing on the back. There is no way to date when this may have happened.

jim

[David Keller NC]

"Almost all the ones I get are not laminated - they're solid steel. The back is usually rough, with the original grinding lines from when the chisel or plane blade was made. Those grinding lines extend into the edge, which causes the edge to be serrated, rather than smooth.

Any ideas why they only sharpened one side? Was it lack of knowledge? Or what?"

Mike - One note on this subject is that the composition of the blade sensitively depends on the age of the tool. Most 18th century tools did not survive - they were sharpened and used into oblivion. Molding planes and a few bench planes are the exception - I've a bunch of them by certifiably 18th century makers. Every one of the irons are laminated. And in the Seaton chest (also certifiably 18th century - though very late 18th century), the chisels and gouges are laminated.

During the 19th century, the composition of tools gradually changed as steel making was industrialized. However, even late 19th century large framing slicks, timber framing chisels, and the like were laminated - I've a few examples of those as well.

However, you're quite right about the backs not being polished, though they are quite flat. Examined under a magnifying glass, one can see that the backs of molding plane irons that saw little use have been ground flat, most likely by the cutler. The Seaton chest book also describes "glazing" which was a much finer grind on the front and back of the tool, at extra cost. Also evident is that the cabinetmaker's sharpening (or perhaps the blacksmith down the street) involved honing the bevel and putting a very slight back-bevel on the blade. Like you, I've observed only a very limited number of irons from the early period that have flat and polished backs.

[Harry Goodwin]

Mike maybe you have been buying either bad tools or bad flea markets. If nothing else my fellow patternmakers and I could do we could sharpen tools and polish the backs of chisels. No question. My carpenter father did the same. To put a rule under a plane blade makes us flinch. Harry

[David Keller NC]

Another comment about 18th century sharpening:

I rather strongly suspect the typical honing was done after the grindstone by stropping. There are records that indicate that a "Turkey Stone" was quite an expensive commodity in the 18th century. However, tripoli and rottenstone (pumice and crushed limestone) were common and cheap.

Carvers have been using a leather strop embedded with rottenstone mixed with a little tallow for many hundreds of years, and I rather suspect that cabinetmakers would've returned their plane and chisel edges to sharpness in the same way. This is, in fact, what I do in my own shop - the waterstones typically don't come out unless I've nicked an edge, or the hollow grind has dissappeared on the bevel. And it's very, very fast - 3 or 4 strokes, without even removing the cap iron, and the plane is just as sharp as it was when it came off of the 8000 grit waterstone.

As to why these strops have not survived, one reason is that the utility of a piece of leather, which was relatively much more expensive than it is today, would've pretty much mandated that it be put to a secondary use when found among grandfather's tools be descendants that weren't interested in cabinetmaking.

[Mike Henderson]

Mike maybe you have been buying either bad tools or bad flea markets. Harry

I've learned quite a bit about old tools, and I feel confident that the tools I select to purchase are quality tools - or at least were once quality tools. I don't know what a "bad flea market" would be. I can't imagine there are flea markets which only carry "good" tools, and other flea markets which only carry "bad" tools.

In any case, many of the tools I've purchased have been on eBay, which represents a pretty good cross section of sellers and tools.

Of course, there's always the chance that I've always gotten the worse tools available, but statistically that's fairly unlikely.

Mike

[Ian Gillis]

Additionally, no one has yet reported (in this thread) that they bought an old plane with a flattened back on the iron (that hadn't been done in modern times).

I think our ancestors just sharpened differently than we do (as suggested by several posters).

Mike

Hi Mike,

I was examining an old razee jackplane today with a view to inletting a new piece into the sole to close the mouth. The plane came to me at an auction along with a toolchest and a few boxlots of assorted tools. I was able to date one Stanley Bailey plane in the collection to the 1880's, and some auger bits to the same period. Undoubtedly he added tools throughout his career, and I can't date this wooden jack with any certainty. It's pre-war... maybe pre-Boer War.

I pulled the iron out to have a look. It's a laminated iron, better than 3/16" thick at the business end. The blade had been lapped to a near mirror finish. I say "lapped" because there is a bit of dish in the back that is untouched. The bevel is rounded but finely honed -- the iron passes the thumbnail tests for both sharpness and smoothness.

The fact there's no rust is not surprising, I have lots of cutting tools from the same toolchest, which is a bit musty, but apparently protected its contents for a generation after the original owner's death.

So, there's one for ya! I'm sure if I pull apart more of this fellow's woodies I'll find the same thing. It wouldn't have struck me as unusual the first time I scoped them out because I'd sort of expect it.

Cheers, Ian

[Mike Henderson]

It's good to hear, Ian, that there's at least one ancestor craftsman who flattened and polished the back of a plane iron. It appears to not be very common, however. Certainly I've never seen one.

Mike

[Ian Gillis]

Me again,

I was in the shop tonight anyway, so I dug out some tools from the same batch and had a look.

My apologies for the photos, reflective surfaces are a bear to photograph.

However, I think you'll get the idea. I did no cleaning or polishing of any kind on these pieces.

Bottom left is the jackplane iron I mentioned earlier, bottom right is a gutter plane iron. Top left is a firmer chisel, and the one on the right is a broken bevel firmer that someone must have used to jack up a house. The soft iron shaft bent ok, but the brittle "bit" snapped.

Cheers,
Ian