Archive for the ‘Uncategorized’ Category

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Dental Hygiene Sawmaker Style: A Close Shave With Occam’s Razor

June 18, 2010

How many times have you heard it said that sharpening a saw is easy? Or worse, that it’s no harder than sharpening a chisel or plane iron? Now, show of hands, how many of you believe that? Yeah, I didn’t think so. I don’t believe it either.

I tend to think that saw sharpening is challenging enough that once you get it you feel as though you’ve accomplished something. It’s neither the hardest nor easiest thing you’ll ever do. Lots of people try it and have trouble. I remember when I first learned to do it I started out like everyone else following all of the steps you are supposed to follow—it didn’t take long for me to realize that some of what I was doing seemed downright unnecessary. So I started to think it all through for myself from scratch, and what I wound up with is a method for sharpening saws that I use to this day. I’m willing to bet that if I showed you how I do it, even if you’ve never been able to do it before you could get it.

Probably most of you already know what Occam’s razor is, but here it is quickly anyway—it’s the idea that given two explanation for something, the simpler of the two should be preferred. That’s basically all I did with saw sharpening. Gave it a close shave with Occam’s razor. I don’t expect everyone to agree with me—when was the last time you saw everyone in woodworking agree about something? I don’t either think the other way of sharpening saws is wrong—that would be foolish; it obviously works and serves many people well. I guess my larger point is simply that I don’t think there is just one right way to do it.

There are a number of smaller differences in what I do, but the biggest and most obvious one is that I file from just one side of the saw. I don’t file half of the teeth then flip the saw around to file the remaining teeth. That works, but I think it is needlessly convoluted for most filing. The only filing for which flipping the saw around is actually necessary is for sloped gullets, but I don’t think sloped gullets are worth doing most of the time anyway. In dry hardwoods, which is mostly what people are cutting, I think what people really need are simply very sharp and well tuned saws.

The thinking behind filing half the teeth then flipping the saw around is that by doing so you equalize any errors. However that isn’t really what happens—that would only be the case if you did the same thing to the saw from both sides. But in reality you don’t do the same thing to the saw once it’s flipped around. Things change. You rotate your file to assume the proper rake angle while now filing with the teeth facing the other direction. On paper you are using the same rake angle, but in practice you are in fact introducing more physical manipulations of the file and more chances for inconsistency and error. It seemed to me that you could skip this whole rigmarole and simply file every gullet while maintaining a single physical rake orientation for the file.

Working this way gives you a big advantage. When shaping teeth you can work directly on any tooth and in any gullet you wish that you see needs adjusted–you don’t have to save any until you flip the saw around. You are freed up to pay attention to the things that are really important when sharpening a saw—you aren’t observing any longer what needs to happen from which side of the saw.

I find working this way remarkably accurate. It just doesn’t involve the usual acrobatics of saw sharpening as it’s come to be practiced. I think the received wisdom on the topic is something that sounds so compelling when you hear it, people haven’t really questioned it. But I do think there is some precedent for sharpening saws the way I do—if you read the passages on saws in Moxon, it seems pretty clear that he’s describing a saw being sharpened by filing in every single gullet—he says it pretty clearly actually. He describes filing one tooth then says to file all the rest—no skipped gullets. When he writes about setting teeth, then, he does describe skipping gullets. So I think he writes just exactly what he means. I think the more interesting question would be why people ever started flipping saws around to begin with?

There are of course objections people could raise, so let me address them. What about the burr created by filing? If you file from just one side, it will be all on one side of the saw—won’t that affect how the saw cuts? Not in my experience, no. Not at all. It’s something that sounds good on paper but that doesn’t amount to a hill of beans in practice. Saw sharpening is full of stuff like that—a theoretician’s cornucopia. If you are creating burrs that big and intrusive when you file there’s either something wrong with your file, or how you’re filing, or with the steel you’re filing.

Another item like that deals with filing into teeth set toward you vs. filing teeth set away from you. Won’t the ones set away from you get sharper than the ones set toward you, as the steel will cut more smoothly on the ones set away from you? Again, no, not in practice. Maybe under an electron microscope, who knows. But in practice it doesn’t matter at all. What about big and little tooth? Won’t you be constantly struggling to keep the teeth set toward you the same size as the ones set away from you? Not really. You have direct control the whole time over the size of the teeth—you simply remove metal where it is needed and don’t remove it where it’s not needed. It’s very direct and intuitive.

What about crosscut teeth? Do you file them from one side too? Sure. If you were to flip a saw around you’d file fleam in from opposite directions anyway—there’s still less muss and fuss when you don’t flip the saw. You just keep the same rake angle and only change your fleam angle—the back of one tooth is the front of the other on the opposite side of the saw. It’s the same geometry, just filed in from one side of the saw, not from two.

What about tiny errors in tilting your file? Those would cancel each other out by flipping the saw around? Sure they would, if your errors were actually just a single consistent error repeated over and over again the whole time. Good luck being that consistent with your errors. There’s no such thing as filing that doesn’t involve errors. Tiny random errors don’t adversely affect anything. I think this is another case of theory and practice not matching—nobody is perfect, nobody. Our errors aren’t even perfect errors. I think we imagine our errors are more consistent somehow than they are. If we did have some consistently noticeable tick in how we filed that was bad enough that it adversely affected the saw and made it pull to one side or something like that, don’t you think you’d be better served fixing your filing technique? It would take an error of that visibility and magnitude to cause a problem—the normal random sorts of stuff that happens, it doesn’t matter which side of the saw it happens from.

So what do you think? Anybody want to learn to sharpen saws? It works. I promise.

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Thanks for the Great Show

June 6, 2010

I just want to say thanks to Lie-Nielsen and Popular Woodworking Magazine for putting on such a nice show this last weekend. Having John Economaki there, with Kevin Drake, as well as the guys from SAPFM, it would have been worth going even if I hadn’t been showing my own tools. A big thanks as well to all of you who came from near or far to make the show such a nice time. Here are a few pics from the show.

A bit of the LN Area

Chris teaching at his bench

John Economaki, always thoughtful and interesting

Kevin Drake in the hat, with his innovative tools

Deneb, the one and only

SAPFM’s Brooke Smith working on a ball and claw foot, making careful wasting cuts with my dt saw.

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Lie-Nielsen Event This Fri-Sat

June 1, 2010

If you’ll be in the area this weekend stop by the LN event at the Popular Woodworking offices in Cincinnati. Lie-Nielsen puts on these events, and they very kindly invite other tool makers to join them and show their own wares. If you’ve never been to one of these events before, don’t be surprised if you see all of that LN bronze, brass, and steel in one place for the first time and have to take a knee or ask for a glass of water. You might even want to bring an extra pair of shorts to play it safe.

At this event I’ll be there along with John Economaki from Bridge City Tools, Kevin Drake from Glen-Drake Toolworks, members of SAPFM, and of course the staff of Popular Woodworking Magazine. Any one of these attractions would be worth going to see if it was the only one there, so to have it all going on at the same time is pretty neat.

I’ll have with me maybe half a dozen demo saws that people are welcome to try out. It will be very laid back—just me at a bench with my saws. Stop by and check them out up close. I’ll answer any questions anybody has and otherwise will just enjoy hanging out.

Here’s a link to the schedule and directions.

Hope to see you there.

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A Bone to Pick

May 21, 2010

You guys ever read a book by the late wood finisher George Frank, titled, “Adventures in Wood Finishing”? Great book. His stories are well written and a lot of fun to read. Plus they have lots of interesting tidbits in them about wood finishing. Here’s a link to the book at Amazon:

Adventures in Wood Finishing, by George Frank

One of the stories in the book is about a set of huge doors George was commissioned to build for the Metropolitan Museum of Art in NYC. The catch? He wasn’t allowed to apply any finish to them—a tricky situation. So how did he manage to “finish” the doors without finishing them? He burnished them.

Interestingly, saw handles used to be burnished for a finish.  The handle maker would use a piece of bone to burnish the beech wood and close its grain.

Over the last year I’ve mentioned this treatment conversationally to people and have had it requested several times. It produces a surprisingly comfortable handle, and a very attractive one too.  It’s remarkable how shiny the wood gets, and without any film or oil applied to it. The end grain especially looks almost glassy.

It’s kind of like going back in time and seeing what a saw handle would have looked like brand new a very long time ago—quartersawn beech with a burnished finish. Not all handles were burnished, though, just the better ones. And no doubt I fuss over my handles a lot more than the old handle makers fussed over theirs. But the basic look of the wood and everything, it’s all there.

I used to wonder why the old handle makers bothered using bone—why not just use a harder wood? Burnishing is burnishing right? But then I made a burnisher out of bone and no longer wondered anymore—its surface was the perfect combination of hardness and smoothness.

My burnisher is made from a piece of beef bone that I bought at a pet store. It’s real bone, just already defleshed and sterilized, so all the prep work to the bone is already done.

I cut out the piece I wanted with a hacksaw then ground it to shape and polished it up. I had access to a photo of an original handle burnisher from England, so I knew the basic shape to shoot for. Beyond that I refined the edges and surfaces into contours I thought would be useful.

Of course someone could say that a handle finished this way will become soiled from the dirt and oils from your hand. And that brings us back to George Frank and his doors—some people saw the doors and found them dirty, and others saw them and thought they had a wonderful patina. The truth is, any handle will patinate from use. I for one don’t think the signs of honest work are something to be avoided.

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Welcome to the New Website

May 16, 2010


Welcome to the new Eccentric Toolworks website and blog. I’ve consolidated the two in order to give you something more compact and user friendly. In addition to the new look and some other changes, such as the gallery page and the lists of links in the sidebar, please note that the url has changed—just http://eccentrictoolworks.com now.

I hope you like the changes and enjoy your visit.

(Bow Saw Toggle)

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April Is the Cruelest Month

April 29, 2010


At least that’s what T.S. Eliot said in his landmark poem “The Waste Land.” I’m not buying it, though. It’s been a darn nice April here at the Toolworks. Granted I spend most of my time in a tiny subterranean shop sucking in the radon, but the Spring weather has been especially pleasant this year. Trees budding seemingly overnight, bulbs tucked away all over the lawn deploying their stems in perfect synchrony. It’s been a quiet symphony of color and slow motion.

The cats were plotting pirate-like mutiny after being cooped up all winter–they burst outside but were promptly incapacitated by warm patches of sunlight. The one looked up at me and squeaked, “Solar energy is the future, man.”


So today I thought I’d take a few minutes and go outside to take a few pics of a tenon saw I just finished up. It’s got a subtle new twist on the lamb’s tongues I’ve been carving. I always get asked how long it takes to make a saw. It depends. It takes as long as it takes, which varies from one type of saw to the next, and which varies from saw to saw anyway. Obsessing over time only makes sense to me if your goal is to make a lot of something; so that is not what I do. I attend to the details of what I’m doing, and when they’re done, I’m done. Simple enough.

But generally speaking tenon saws are among the most time consuming that I make. They have closed handles, long folded backs, and big thin blades. Everything must be a very particular way before it leaves the shop, and nothing gets that way by accident.


The handle in front is the same one pictured above. The handle behind belongs to a panel saw not quite finished. Thanks for looking. Hope your April has been as nice as mine.

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Waiter There’s a Fly Press in My Soup Part II, Punching Saw Teeth

April 13, 2010

We got off to a fast start in our first installment. In case you missed it, we had videos of Japanese saw smiths, we gunned down a burglar with a Foley retoother, and we dusted the cobwebs off Charles Holtzapffel. A veritable smorgasbord of sawmaking curiosities. I’m going to assume you’ve read that installment and won’t repeat much from it. One thing I will repeat, though, is Charles Holtzapffel’s description of a toothing gauge. It will be helpful to have it near at hand. He writes:

“The teeth of saws are for the most part cut in the fly-press. …Two studs are used to direct the edge of the blade for the saw to the punch, at the required angle depending on the pitch or inclination of the teeth, and an adjustable stop determines the space or interval from tooth to tooth, by catching against the side of the last tooth previously made.” (Holtzapffel, Turning and Mechanical Manipulation Vol II, p 942)

This description was the only actual description of any kind that I had to work from. But of course I also had in mind what I needed a toothing gauge to do—so ultimately what I did was work backwards from what I needed, carefully considering Holtzapffel’s description as I did so. Here is what I came up with.


This first shot shows the gauge from above with some of the parts labeled. The second shot shows the gauge installed on the press.

The whole thing sits on the fly press table and is fixed to it by the bolts that pierce either end of the gauge bed. The heads of the bolts fit into T-slots in the fly press table. You’ll notice that the lefthand nut that fixes the gauge is about half the height of the one on the right. That is because I feed the saw plates from right to left, so the plates pass over that lefthand nut; it initially did stand up higher and got in the way, so I cut it down.

Probably the biggest thing you’ll notice is that my gauge has a solid fence and no studs. Holtzapffel’s description of two studs acting as a fence seemed less effective a solution than simply having a solid fence. For instance, two studs that lead the blade to the cutter would probably be placed a few inches apart in order to be an effective fence—but then once the blade was advanced to a certain point, it would no longer be supported by both studs. A solid fence, by contrast, never loses contact with the blade, and can even cross over and support the blade on both sides of the cutter.

The fence is adjustable not only for rake angle but also for depth of cut. What’s more, the same cutter can be used to cut all sizes of teeth. The size of the teeth is determined by how closely and shallowly the teeth are spaced. For the smallest teeth the old makers would have used a punch that punched several or so teeth at a time. I haven’t gotten around to making one of those yet but plan to.


The punch I did make is made from W1 tool steel. The lower die is made from O1 tool steel. The bottom die is held in place with a pair of recessed screws; they are recessed so that the saw plates can pass over them without the heads of the screws interfering. The W1 punch was filed to shape to fit the lower die and is held in an auxiliary tooling holder that fits into the fly press ram. The die and punch are made from different types of tool steel just because those were what I had on hand. The O1 is more ideal for this type of work, but the W1 works fine.

The teeth are spaced using a little indexing stop that I made from scrap steel. It is adjustable both from side to side and from front to back.



It works like the one Holtzapffel describes–it registers against the last tooth punched. That registration, combined with control of the rake and depth, is what produces good teeth. All three variables have to be regulated–if you adjust spacing without adjusting depth of cut, for instance, you wind up with all sorts of odd permutations, some of which result in the punch just nicking the blade. Like this:

Now that you see how the gauge goes together, let me show you how I use it. The first thing to do is to register the punch with the lower die. To do that I loosen the bolts that secure the gauge bed as well as the set screw that hold the punch in the ram. I move everything around until it meshes just right then gently snug it up. The punch and die are both made with relief angles so that they make contact just at the point where they shear the saw platel. Then their surfaces retreat just a bit. The punch and die either needed relief like that, or they needed to be perfectly vertical, and it was simply easier to give them a tiny amount of relief. If they sloped in the other direction they would spread apart as they engaged, and as the punch was raised you’d see that the cutting edges no longer meshed.

The next thing to do is to set up the fence and indexing stop. To do that I use a piece of saw plate that already has the desired tooth configuration–I place it against the fence and place the cutter in one of the gullets. I adjust the depth and angle of the fence so that the cutter fits perfectly in the gullet. Then I gently snug down the bolts that hold the fence.


With the plate still in place I move the tip of the indexing stop into place against the tooth beside the cutter. Basically I am aligning everything just as if it had punched the very plate I am using for alignment purposes.

I snug up the screw that holds the indexing stop, and I’m ready to go.

The pictures of actually using the press don’t look much different really than the pictures of setting it up. Only now the cutter is going up and down, and I’m not fooling around with any wrenches. Here’s a picture of just starting out punching a saw plate.


Here is the same plate much farther along.

And below is what the plate looks like with the teeth nearly, but not quite, finished.

So that’s about it. I’ve been very pleased with how the toothing gauge has performed. For me this method strikes just the right balance between thoughtfulness and expedience and seems to fit nicely with the other processes involved in making my saws. At some point down the road I will experiment with a second gauge that utilizes the two studs for a fence like the one that Holtzapffel described. I still feel that tugging at me. But for starters I wanted something that I knew would work and that I could rely on right away in my own work. Thanks for reading.