Wednesday, February 13, 2008

A little more about chisels

Eric posted a nice comment in my last blog entry and asked:
What the heck is a dovetail chisel or fishtail chisel? What's the difference between Western bevel and Japanese bevel? And where do you recommend to buy them?
As I wrote before, Japanese chisels are forged with two types of steel that are welded together during the forging process. One thin layer of very hard steel and a thicker layer of softer steel that will support it. The hard steel will become the back of the chisel and the cutting edge and this is the reason Japanese chisels will keep a sharp edge for a longer time than a western chisel.

Some tests like the Bench-Chisel Review published by Fine Woodworking Magazine will give you a clear evidence of this.

All Japanese chisels that I know of have a hollow (or more than one in wider chisels - see top photo) in the back which makes it easier and faster to flatten the back. Otherwise it would require a lot of work to flatten a large surface of very hard steel.

Usually Japanese chisels are somewhat shorter than western chisels, and I like this feature since my hand is closer to the work and I find it easier to control. Other than these I would say there aren't any more differences between Japanese and western bevel edged chisels.

As far as the shape of the blade goes, you can find chisels in many different shapes and some are best suited for certain tasks. Bevel edge chisels are the most common since they are the workhorse of a cabinet shop and useful for most tasks.

A timber framing chisel, often used for more heavy duty tasks, won't have bevels on the sides of the blade and while these can be very good tools for chopping large mortises in a 4x4" or for paring tasks, for smaller projects you'll find that the lack of bevels will usually become a problem when reaching the tight corners of a small mortise.

A dovetail chisel on the other hand has a triangular section, which means that it will get into the tight pin socket between two tails (provided that you're cutting thin tails like our friend Kaleo Kala enjoys - the photo on the homepage of his website is a good example of this) and this is the task where they really excel.

You should avoid to use these for more general tasks as they're not as strong as a bevel edge chisel.

Currently you can find western type dovetail chisels, i.e. made with just O1 or A2 steel like the ones made by Ashley Iles or Blue Spruce Toolworks.

Fishtail chisels are yet another specialty chisel. The cutting edge is shaped in a way that it will get into the tail sockets of half-blind dovetails and you can use them to clean the left and right side of the sockets. An alternative is to use skew chisels (usually sold in pairs - right and left skew angles) but this will require two tools instead of one.

Again, like the dovetail chisels, you can get western type fishtail chisels. It's just a question of preference. I tend to favor the Japanese ones.

As far as where to buy them, I would recommend you to check out the online stores (these will often have a wide range of brands and prices to choose from) and then see what's available locally.

In Europe I would recommend you check out:
In the US you will have more choices but these are my favorites:
In the end you can't go wrong with either a good quality western or Japanese chisel, some will prefer the western tools while others will favor the Japanese ones.

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Tuesday, February 12, 2008

A basic set of hand tools - Part III

Choosing a set of chisels may be a fairly simple affair.... they even come in sets! But which one set should you get? I'd say none!

Chisels

If you are on a budget, a set of three bevel edge chisels (1/4", 1/2" and 3/4") will get most of the job done. It's nice to have a few more sizes, but I'd rather have only these three and have quality chisels than have all the sizes available from 1/8" to 2" of lower quality steel.

A lower quality chisel will be a rather disappointing tool. It wont keep a good edge for long, it may chip or get blunt easily and even when properly sharpened they won't cut through wood effortlessly.

There's nothing worse than cutting wood with a blunt tool. It tears the wood fibers instead of slicing them and your exposed joinery won't look very good.

These days Lie-Nielsen chisels are rated very high, these are expensive tools but you get what you pay for.

In my shop I have some western style bevel edge chisels but the ones I wouldn't live without are my Japanese chisels. These are easy to sharpen and hone and will take a very sharp edge that will last for a long time.

Japanese chisels are somewhat different than the western ones. They are forged with two different types of steel, one that his very thin and hard and will become the back and the cutting edge, and on top of this is a softer steel that will support it.

Furthermore there is a hollow in the back of the chisel so it is easier to flatten the back that is made of very hard steel. Some of the better chisels will have multiple hollows in the back for extra support. A good feature on larger chisels.

Due to their construction, the Japanese chisels can't be hollow ground and must be sharpened on a waterstone or oilstone. And if you want to keep your chisels for a long time, never lever chips of wood if you're cutting mortises with them. Take it easy on these and get a mortise chisel for the job.

So, what is on my set of chisels? Here's what:
  • 3mm (1/8") Japanese dovetail
  • 6mm (1/4") Japanese dovetail and western bevel edge
  • 12mm (1/2") Japanese fishtail and western bevel edge
  • 19mm (3/4") Japanese bevel edge (multiple hollows)
  • 25mm (1") Japanese bevel edge (multiple hollows)
As you can see, I managed to get all the sizes from 3mm to 25mm but instead of just buying a set I built my set based on my needs. For small sizes I chose dovetail chisels, these are quite useful for working in small joinery, and for larger sizes I chose standard bevel edge chisels which can take a little more abuse.

The western chisels are somewhat redundant but I'll use them for more coarse work and will save the edges of the Japanese chisels for the finishing work.

The fishtail chisel is what I'd consider a specially tool, it has a very thin blade and excels at cleaning the pins on half-blind dovetails.

My next purchase will be a long paring chisel around 36mm, but this one will have to wait.

Next installment: Handplanes

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Friday, February 8, 2008

Hand tool nirvana

In recent years we've seen small independent companies enter the market offering high-end woodworking tools, quite often handmade with a degree of craftsmanship that surpasses what most would expect from a quality tool.

Can you imagine a jointer plane costing over $9.000? Well... take a look at this 28" steel and ebony torpedo and you'll see why. This thing will almost plane boards on it's own.

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Friday, February 1, 2008

Wooden block plane sketch

I've been playing with the idea of making a wooden plane for a while and decided to start with a small block plane to replace my vintage Millers Falls No. 57. The alternative would be to buy a Lie-Nielsen #60 1/2 but those little wonders are expensive....

I want it to be a low angle plane but making a wooden plane with a 12º bed is out of question, the body would be too thin to handle the strain, so I decided to take a different approach and instead of making a bevel up plane this will have the blade resting with the bevel down on a 37º bed.

This design should have the same cutting effect of the #60 1/2 since the angle of attack of a bevel up plane is the sum of the bed angle and the angle of the bevel of the blade (usually 12º + 25º respectively).

Pictured above is a sketch I made using SketchUp to have an idea of the dimensions. I guess it will work out fine!

The SketchUp model isn't perfect but will give you an idea of all the parts and dimensions.

Attached files

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Making a wood plane from a kit

While browsing some of the woodworking videos on YouTube I came across this one from Ron Hock showing how to make a handplane from kit. The video also shows how to sharpen the blade using the ruler trick often attributed to David Charlesworth.
In the end of the video you'll also see the method used to tune a wooden handplane, with just a few taps you're good to go. Simple and effective!

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