EasyWood

These are an interesting concept as found by the Roving Reporter, from Easy Wood Tools.  It is a concept I have seen elsewhere, but these look a well refined solution.

easyEach has a carbide tip, so sharpening on the fly is not necessary, as the tool dulls with use, rotate the cutter, and finally replace it.  Of course, if you have the Tormek Sharpener with the Blackstone Silicon wheel, then you can resharpen the carbide cutters.

Haven’t seen these in person, so I don’t know how they shape up in reality, or how they would compare to my Hamlet chisels for example.  Although carbide cannot be sharpened to the same degree as tool steel, in practice most wood turners don’t sharpen their chisels to the nth degree in any case, and the long durability of a carbide edge has a lot of appeal.

Scratchin’ out a living

When you are used to using power tools and machines for your woodworking, it is easy to forget that sometimes a handtool is the best tool for the job.

They are quieter (much, much quieter), safer (although any sharp thing can cut), and often can get into places denied to power tools.   They also can have a different method for removing material. Where both can slice, only a handtool can scrape.  (Now I’m sure someone will tell me I’m wrong…..)

Scraping has its benefits.  It avoids tearout, as the blade is not parting material ahead of the blade – lifting and cutting.  Think of all the adverts on TV about shavers, where the blade lifts and cuts the hair.  If you are lifting timber, there is a chance more will lift than you intended, and tear out.  Scraping has the blade at a different angle of attack, with the cutting edge trailing behind, rather than leading the way.

Scraping is used in a number of hand tools.  For planing a surface with torturous grain (burls and the like), you can get planes with the blade set vertically for a scraping cut.  You can use scrapers (a piece of steel with a fine burr to perform the actual cut) as an alternative (and superior to) sandpaper.  And you can use a scratch stock as an alternative to a router.

It is a very simple tool – a piece of spring steel with the required profile cut into it.  And a holder.

You can make your own, or check out this one from Hock Tools (Ron Hock being very well known for the quality of his plane blades).

Hock Scratch Stock

This is available from Professional Woodworkers Supplies in Australia, who sell items from the Hock Tools’ range.  The body is made from a laminate of bamboo, which has good water resistance, and shape stability.  Instructions for using the scraper can be found here.

Where noone would consider manufacturing their own router bit, this comes with a second piece of tool steel so you have plenty of opportunity to create just the profile you want.

I came across an interesting concept while looking at these scratch stocks (and especially the supplied profile).  It used to be quite common for this profile to be used on the leading edge of a kitchen bench….underneath.  The purpose was as a drip arrestor.  Any liquid spilling and running over the edge would gather at the bottom of the curve of the profile and drip off, rather than continuing on its journey into one of the drawers (often the cutlery!)  Simple idea – pity it seems to be forgotten by modern kitchen manufacturers.

A very simple concept, a very simple tool, the ability to make your own profiles, and the ability to deliver that profile just where you need it, right out of reach of powered tools.

Handplanes, a quick look

I’ve been avoiding this topic for quite a while, as much because there are so many knowledgeable people about there who live and breath these traditional tools, that I know I won’t be able to do them justice. But putting that aside, there is a surprisingly large learning curve to traditional tools and what they are capable of.

Woodworking has been around a lot longer than our planers and thicknessers, tablesaws, routers, drop saws etc etc. How wood was shaped and worked was often with handtools, and a group that has survived the ages are handplanes. Of the vast majority of traditional handtools that existed, at least you can still walk into a hardware store and buy one. How good they are is another matter entirely, but there are still some quality handtools around.

I said recently that I’m a bit of a strange fish where it comes to some things, and this is no exception. I came across a toolmaker at the Melbourne Wood Show a few years ago, and was really inspired by what could be achieved with such a basic form. He was (and is) Terry Gordon, and I really enjoy owning and using some of his planes. (HNT Gordon Planes).

So onto planes themselves. I mainly only have HNT Gordon planes to show you at this stage to highlight my points. In a roundabout way, this is another aspect of the start of the sharpening exposé. After all, when you are talking about sharpening, there has to be something that needs to be sharp!

It is said that there are the big 4 planes that all complement each other, and all fill different roles.

They are: the smoothing plane, the trying plane, the shoulder plane, and the low-angle block plane. In addition, I’d add the spokeshave, and the jack plane to complete the basic set. (And at this stage, I still need to add a spokeshave and jack plane to complete my set!)

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Now I know that what I have here do not look like the planes you normally expect to see, but other than quite a different looking form to the modern plane, they still perform the same function.

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I also really like the fact they come in such a traditional looking box…

The left-hand plane is the low-angle block plane. The low angle makes it very good for end-grain, and given it’s small size, is very convenient for a number of quick shaving jobs (like taking off the edge of a board)

The plane on the right is the shoulder plane. It is unusual, because the blade gets right to the edge of the plane itself, so planing the shoulder of a tenon is achievable (and where it gets its name from). It can also be used to cut a rebate, or a dado.

The last two planes really do complement each other, and as you can see, look quite like each other, just different sizes. They do have different functions. The large plane is called a Trying Plane, and is used to flatten a board. Because of its length, it rides across high spots, allowing them to be planed down, rather than following the rise and fall and just smoothing them. It can remove quite a bit of material quickly, and is the original version of what we know as a jointer (or planer) when talking about powered tools.

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The other is a smoothing plane. Capable of removing the finest of shavings, and leaving a surface so smooth and shiny, that only a light touch with 400 – 600 grit sandpaper is needed before reaching for the finish.

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The smoothing plane can cut so fine, that you can easily read through the shaving it produces.

So these are the 4 planes, and each needs a razor sharp blade to function. In the case of the trying and smoothing planes, I have a very thick chunk of high quality steel, and for the smoothing plane in particular, I chose a cryogenically treated steel. Bloody hard to sharpen (because it is so hard), but it holds a beautiful edge. I sharpen these on Japanese waterstones, using the Veritas Mk2 Honing jig. (The blades are so thick, you can pretty easily do it by hand, but I don’t get enough practice to trust myself.)

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Here in this final image, I decided to measure the thickness of the shaving I was getting off the smoothing plane. You might be able to see it, reading 0.01mm, or in other words approximately 4/10000th of an inch (ie about 1/2 a thousandth of a inch). I’m probably beyond the capabilities of the gauge to measure that fine. I think that is thin enough!

Steel

Steel. Perhaps a strange topic for a woodworking site, but then, so many of our tools, and particularly the sharp edges that actually work the wood are made from it, so it is useful to know a bit about it. In the near future, I will be doing an exposé on all things sharpening, so getting to know steel is really the start of that process.

(I will be pretty general in the descriptions, so don’t be surprised if you can drive a bus through my definitions!)

There are many, many versions of steel. Steel is not an element, but a compound of Iron (Fe) and Carbon (C) (and is actually called an interstitial solid solution, as the carbon atoms fit into the gaps in the Iron atom structure). In addition, you can add other metals into the one material, which is called alloying, and there are a huge variety of steel alloys out there with all sorts of different properties. I’m going to pretty much ignore the alloys at this point, and just focus on carbon steel.

Now carbon steel is just not a bunch of Fe atoms in a grid, with the carbon atoms in some of the gaps throughout the material. If this were the case, the concept of heat treating, tempering, quenching etc wouldn’t have any effect. What there is in fact, are areas of pure Iron (called a-iron or ferrite) then others which are a combination of Fe and C, which is iron carbide (also known as cementite), and is not a discrete molecule, but a crystal lattice containing iron and carbon atoms in a ratio of 3:1, written Fe3C.

If you have a huge amount of carbon, then you have massive amounts of cementite and ferrite (pearlite – see below), and even areas of pure carbon, and this is where we get into cast iron, which is not used for making sharp tools (very hard, and way too brittle!)

Back to steel. Carbide, as we experience it as woodworkers is generally tungsten carbide, a very brittle, very hard material that is used for producing durable cutting surfaces. Iron carbide (cementite) is similar, hard, but brittle, and if in the right amount gives steel a real edge over pure iron (sorry about the pun).

So what happens when we take our molten steel, and cool it to form our chisel or plane blade? If we let it cool slowly, it will have time to form the normal structures, and will be our basic steel – machinable, hard, but nothing special. It will have (and this depends on the % of carbon) grains of pure ferrite, then others that are a mixture of ferrite and iron carbide. It is these grains that are a mixture that give steel its ability to be heat treated (ok, gross generalisation). As these grains form, they produce a lamellar (plate-like) mixture of ferrite, and carbide, known as pearlite. The steel at this point can be cut, ground etc, to form the desired shape for the plane blade, chisel etc. The steel is ok, but not tough enough or hard enough to be used for a cutting edge. That’s where heat treatment comes in.

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Pearlite
White areas are ferrite (Fe) , ‘worms’ are platelets of cementite (iron carbide, Fe3C)

The steel is then reheated, but not to melting point, held at the required temperature, and then cooled quickly. If you cool it slowly, you form coarse pearlite, which isn’t very hard, and therefore not useful (for us). Cool it quicker, and you get finer pearlite (ie smaller, thinner, and more platelets of carbide). This is harder and stronger material. If you cool it even faster (quenching), you form a new structure, called martensite. Martensite is supersaturated with carbon, and the change to the iron lattice means the atoms can’t slip over one another easily so the material is very brittle and very hard. The faster you can cool the steel, the more martensite is formed (and the smaller the individual grains). Although this transition to martensite happens very quickly, not all the material can get there in time, and retains the original structure. To force more of this to martensite, we need to cool the steel even further, well below room temperature, and is called cryogenic treatment. So now we have an extremely hard, brittle tool steel. (Yeah, I’ve generalised heaps here, but you get the jist). The structure is good – we have a very fine grain structure, but we need to ensure that there is sufficient ductility in the steel, so it can survive being pounded by a hammer into hard wood! (In other words, we want it hard, but also tough).

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Martensite

This is done by tempering – reheating the steel until we get just the right combination of ductility and hardness, and the result is called tempered martensite, an ideal combination of toughness and hardness in our resulting tool. The brittle martensite is transformed into a fine dispersion of iron carbide particles in a tough ferrite matrix. The carbide stops dislocations and slips in the structure (so the material can’t shear and fail, ie making the material hard (and is not unlike how the atoms of an alloying material help make a material hard)), and the ductile ferrite can deform locally, arresting any cracks that try to form in the structure (so the material is less brittle).

Thus we have a blade, hard and tough, with a very fine grain, ready to be sharpened to a mirror finish (and if you have 2 surfaces that are so flat as to be mirror-like, meeting at an edge, that edge will be razor sharp).

***Update*** Here are a couple of articles about the practical side of heat treating blades, and are definitely worthwhile getting to see this done in practice, as well as the theory above***

http://villagecarpenter.blogspot.com/2008/02/heat-treating-tempering-blade.html

http://www.hocktools.com/diyht.htm

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