We are on the verge of releasing a four-hour video on building a full-blown 18th-century French workbench in the next week or two. The video, starring Will Myers and me, is as complete an explanation of the process as we could manage, and it covers everything from dealing with wet slabs to what is the appropriate finish for a workbench.
In between, Will and I discuss a variety of techniques for completing every operation necessary to build a bench, no matter what sort of tools you use. For example, for making the tenons on the stretchers, we show how to cut them by hand, how to cut them on the table saw and even how to use a Domino XL in the process.
The video will be available to stream through our website, and (if all goes to plan) you will be able to download a copy of it so you can watch it while not connected to the Internet.
Before we launch the video, two things have to happen: We have to settle on the retail price of the video, and I have to complete the construction drawing that accompanies it. Unfortunately, my computer was fried in an electrical storm a few days ago (don’t worry, everything was backed up), but I don’t have a machine loaded with the suite of software I need to make the drawing.
Read the other installments in the “Sharpen This” series viathis link.
People say that “sharp” is like pornography – you know it when you see it.
The problem with that statement is that you cannot see sharpness. When a tool is sharp, its edge becomes practically invisible to light. You can, however, see an edge when it’s dull. If you are confused by the above statements, don’t worry. By the end of this blog entry you will truly understand the difference between sharp and dull.
Let’s begin by discussing the definition of a sharp edge because it is incredibly important. Here it is: A sharp edge is two surfaces that intersect and create a zero-radius intersection.
Like many definitions, this one needs some definition. What does this mean?
Think of a chisel. Its bevel is one surface. The tool’s back is the second one. The surfaces don’t have to be flat; nor do they have to be curved. They just have to meet. Where they intersect is the edge. And when they meet at a “zero-radius intersection” you have a sharp edge.
What’s a zero-radius intersection? This is when the intersection of the two surfaces is not a radius or a rounded-over bit. Instead, in a best-case and theoretical scenario, the bevel and the back intersect and share a single line of iron atoms in a crystalline matrix with carbon. That line of particles is what wedges between the wood fibers and separates them cleanly.
That is sharp – as sharp as it gets. So what is dull?
Dull is where you have two surfaces that intersect, but their intersection is a radius or a rounded-over section. A million things could cause this radius to exist. Perhaps the maker of the tool failed to grind the two surfaces so they meet. Perhaps the two surfaces once met at a zero-radius intersection, but then the owner used the tool to do some woodworking. When you push a steel edge into the wood many times, tiny steel particles at the tip wear off, creating a rounded-over radius.
The goal of sharpening is to re-establish the zero-radius intersection.
You do this by abrading one (or both) of the surfaces until they meet again with a zero-radius. Note that this task can be done with any abrasive. A coarse abrasive will do this quickly but leave deep scratches in the edge that make it fragile. Fine abrasives will do the work slowly and you will want to take up golf.
And I repeat: Any abrasive can make an edge sharp. Fine abrasives don’t really make the edge sharper, they just make the edge more durable. But more on that topic in a future blog post.
Meet the Burr So the first goal of sharpening is to ensure you have two surfaces that meet at a zero-radius intersection. But how do you know when you have achieved it? Easy. When you create a zero-radius intersection, a magical thing happens: You create a small metal burr on the surface that isn’t being abraded.
This burr is the heart of sharpening. It is the only thing (other than an electron microscope) that will tell you that you have created a sharp edge. Once you have the burr, the edge is sharp. Polishing will refine it.
So what did I mean at the beginning of this entry when I said “you cannot see sharpness?” Easy. A radius reflects light. When you look at your chisel and see a bright line where the bevel and back meet, that’s the radius smiling back at you. It’s time to sharpen.
But when you are done sharpening, have achieved a zero-radius intersection and have removed the burr (more on that later), there is nothing that can reflect light back to your eyeball. Sharpness is invisible.
That fact is one of the great curiosities of sharpening: It is a great labor to create nothingness (cue the sitar solo, dude).
This is the last call for the three stickers designs shown above. I’m busy designing three new stickers for my daughter Maddy’s sticker empire – these new designs should be ready in August.
You can order a set of three stickers from her etsy store for $6 (which includes shipping) here. Yes, she accepts international orders with a small upcharge.
Or, for customers in the United States, you can send a $5 bill and a SASE (self-addressed stamped envelope) to Maddy at:
Stick it to the Man
P.O. Box 3284
Columbus, OH 43210
She’ll put the three current sticker designs in your envelope and mail them back to you. These are nice, 100-percent vinyl weatherproof stickers.
Maddy turned 21 this year, so I always wonder how much of her sticker profits go to food and how much goes to, ahem, “liquid food.” She assures me she is buying a lot of turkey sandwiches with the sticker money. Can you ferment a turkey?
Read the other installments in the “Sharpen This” series via this link.
When you learn to sharpen, I think it’s essential to do something that is normally a bad idea: Close your mind.
Let’s say you are 5 years old and starting school. The teacher says you need to learn to read, write and speak, and that you can use any and all of the words and phrases from every language on the planet.
It’s unlikely you’d be able to communicate with anyone in your class or your community. You learned the German word for “eating” and the Persian word for “sauce.” But your friend learned the Cherokee and Finnish words.
Instead, the quickest path to finding out where the bathroom is or how to microwave a burrito is to learn a language that allows you to navigate your world. Then you can figure out which other languages you might like to learn.
Sharpening is like that. Every sharpening system is has its own logic, history and subtleties. And while every system works brilliantly, mixing and matching bits from multiple systems is likely to confuse and confound.
Pick one system. It doesn’t matter if it’s oilstones, waterstones, diamonds or sandpaper. Ignore every other system out there. If someone tries to tell you that a different system is better, plug your ears and start shouting “nunga, nunga, nunga.”
Here’s why: About 70 percent of the people willing to talk about sharpening in detail are those who are new to it. They simply love their new system. It makes edges that can shave them bald with little effort whatsoever.
About 29 percent of the people willing to talk about sharpening in detail are trying to sell you sharpening equipment. Most of this equipment works fine, but you don’t need all of it (any more than you need all the handplanes in the Lee Valley catalog to make a box).
And the final 1 percent of people willing to talk about sharpening are idiots like me. I don’t think one system is particularly better than any other. I don’t sell sharpening equipment. I’ll be happy to teach you to sharpen, but you have to promise me you’ll master one sharpening system and use it exclusively for one year before changing your routine or buying different equipment.
I call this “sharpening monogamy,” and I think it’s the fastest route to the sharpest edges.
So step one is to pick one system and sign that pre-nuptial agreement, but don’t buy anything yet. First you need to understand what sharp looks like (and what dull looks like). And you need to figure out the three grits in your system of choice that will grind, hone and polish your tools.
Only then should you get out your wallet.
— Christopher Schwarz
P.S. These sharpening columns are generally not going to allow comments. Why? Well, I think this column pretty much lays out why. If you’d like to take me to task on my approach, I recommend posting your thoughts on your blog.
P.P.S. And if you think this is a “free speech” thing, please read this first.
Read the other installments in the “Sharpen This” series via this link.
After years of working with professional and amateur woodworkers all over the world I have concluded that people who are hostile to handwork tend to badmouth it for a simple reason: They cannot really and truly sharpen.
They might be able to rub a chisel on a rock so their chisels can chop out wood left behind by a router or saw, but beyond that, they are lost.
Think about it: What if your table saw tried to kill you every time you turned it on? (Oh, wait, that’s what it really does do.) OK, imagine if your table saw’s blade had only two teeth on it. You’d hate that saw. You’d tell your students to avoid it. You’d say it was no way to make furniture.
Fixing this ornery saw takes about five minutes, tops: Remove the old blade and replace it with a sharp one. The same goes for a dull chisel or plane blade. Five minutes on the stones (or strop, if you are so inclined) and you are back to perfect.
But if you are unwilling to take a half-hour lesson and perform a few practice sessions to learn to sharpen, then you are going to be forever left with tools that are frustrating, slow, damaging to the wood and awkward.
And that is – I think – the source of hostility to handwork. It’s not that these naysayers think their machines are so fantastic. It’s that they are unwilling to admit they cannot sharpen at a high level.
This is not a supposition. I’ve concluded this after looking at a lot of people’s edges and comparing it to their work and what they say. (The only outliers to my observation are the few people who really can sharpen, but their public personas are based on bashing handwork – yes, these people exist.)
I say all this because today marks a turning point on this blog. Until today, I avoided writing much about sharpening because it is a sticky wicket. There is more misinformation floating around about sharpening than any other woodworking topic (the topic of finishing is a close second).
I have started a new category on this blog: Sharpen This. Articles in this category will show you how I sharpen every tool in my chest: planes, chisels, scrapers, travishers, scorps, moulding planes, awls, spade bits, screwdrivers and so forth. I’ll also attempt to disarm the consumerist economy that has sprung up to capitalize on our craft’s fear of this simple process.
You don’t need a lot of equipment to sharpen. All the systems work. The trick is to pick one system (what I call “sharpening monogamy”) and practice.
And if you are willing to humble yourself before a teacher, admit you cannot sharpen and take a lesson, you can get fixed up with everything you need to know in less than half an hour. (Pro tip: Attend a Lie-Nielsen Hand Tool Event and they will gladly give you a complete and free lesson.)
But if you won’t do this and you continue bash handwork, then I have only two words (and an obscene gesture) for you: Sharpen this.
