15 September 2014

On woodworking: The easiest thing I know how to make, part one.

The idea for this and the next few posts originated with Dale over at Dyspeptic Mutterings. He asked for any help from people who knew about woodworking with an eye to one day making oak and maple furniture. He also asked if anyone knew any sites with very basic and easy plans. I had been toying with the idea of doing a few posts on woodworking, or even starting up a blog on woodworking (I was going to entitle it "The wood slob". Anyone who has seen my shop would know why. Besides, all the really good names are already taken.) but Dale's request made me think maybe I should stop playing with the idea and just get on with it. So, here we go: A series of posts on the subject of the art of working with wood while concentrating on making the simplest project I do: A chequerboard.

It is, as I said, the easiest thing I know how to make, however, behind the ease lies some fairly complex yet basic skills. So I will give you the basic instructions. If you feel competent to go off and get to work, ignore the bulk of what I write with my blessing and encouragement and ignore the long notes. Also, I would have liked to have done a video, but that is currently beyond my capacity. I have taken photos of the process, but, as I have said very often in the past, I suck at photography. Having said all that, let's begin in earnest.

For this project you will need:

pencil or marking knife
measuring tape or ruler
plane (optional)
masking tape
clear finish or oil or wax
light coloured piece of wood (I used pine) large enough to yield an 8X8 piece
A cheap mitre box would be handy as well.

A quick note on tools: it is important to get some quality, but even more important is to learn how to care for your tools by sharpening and tuning them up. There are lots of sites and videos out there that deal with bringing old saws back to life and how to tune up planes. Seek a few of them out. Learning about your tools will also teach you about the craft. But, and this may be disheartening, you also need to know that not only do you need tools to do your work, but also tools to care for those tools, and, in some cases, tools to care for the tools that care for your tools. But take some heart, eventually you have enough to get the job done. I haven't bought any new tools in years.
For step one you will need the wood, the saw, the square and the pencil.

A note about following steps: for the best results, treat every step like it is the only one. When you start looking forward, and trying to run through the each step to get to the next one, and then to get to the finished product- that's where mistakes really start to happen.

Step One:

Measure, mark and then cut the wood into an 8"X8" square.

That's if you already know what you are doing, along with the whole "measure twice and cut once" thing. Also, I am assuming you can get a piece of wood sufficiently large for such a piece. If you can't, you will have to add an additional set of steps involving gluing, clamping and then planing or sanding flat some boards to make a piece of sufficient size. Here's how I carried out this step, with some pictures.

First, I got some wood from my pile. As I said before, I pull pretty much all of my wood out of the garbage- that would be the subject of another post- so my wood generally needs a little work before I can make use of it.

I started by planing the board flat, which also got rid out of the old finish.  I only planed the part above the dado, because I only needed a small piece, and didn't feel like flattening the entire board at this time.  Flattening a board is an important and fairly basic skill, which I won't cover at this time.  For now, find yourself a flat board.

Checking the corners of the board for square. Never assume your corners are square. Always, always check. In this case, the corner was off slightly. I had to square it up before I could proceed with measuring and marking. Had I not checked and fixed it, every subsequent measurement would be off.

Marking the length. Or the width. Hard to say. Whenever possible, I like to lay my ruler on its edge, so the markings actually touch the wood. For the pencil- if you use one rather than a knife- always keep it sharp, and make your marks small. Remember a pencil line has thickness, and lines from a dull pencil have greater thickness. That thickness can distort your measurements and reduce your accuracy considerably. Make a pencil sharpener one of your first and most fundamental pieces of equipment in your shop. Mine is right by the door.

By the way, the ruler is home made. I modelled it after some carpenter's rulers recovered from the Mary Rose. I thought they were cool.

Drawing a line with the square. Most people get it backwards. Do not bring the square up to the mark, the use the pencil to draw the line. Instead, put the pencil on the mark...

...and then bring the square up to meet the pencil. Now you can draw the line. It improves your accuracy considerably.

Now just fill in the rest of your lines. I don't show it here, but what marking your lines, only use the square going across the grain. If you are making multiple markings, always try and use the square on the same edge to ensure consistency. I don't recommend using a suare on end grain. Rather, once I had the line going across the board, I measured eight inches from the edge along that line. I then went to the top of the board, which I had squared up earlier, and measure eight inches along the edge. I then used a straightedge to connect the two markings. The board is now ready for cutting.

I didn't take any pictures of the actually cutting, as I don't know what kind of saw or saws you have. I'll say a word on sawing now, but with a warning: I could write a dozen blog posts on sawing and not scratch the surface. Do not think of what I am about to say as exhaustive. Also, what I have to say comes from my experience and opinion. Take it for what it's worth.

In my experience, it is wrong to think of saws as precision tools. They can be in the right hands, but, for the most part, they are demolition tools. They are designed to make a big piece of wood into a smaller piece of wood, fast. There is a reason why my old shop teacher always told me he should be able to see my line after I made a cut. You get close to the cut with the saw, but the real accuracy comes from your planes and your files, as you bring the edge of the wood to the line.

An average beginner may have a few saws if they're lucky, or at least one of a few. Among the most common are table, circular, and hand. If you have a table saw, read and understand all the instructions, especially those pertaining to your safety. This one is actually the most straightforward to use. Set the fence to eight inches for the rip, and then make a mark for the cross cut and use the miter gauge to make the second cut. Done very quickly with good accuracy, as long as it is properly set and tuned. The tool itself removes all the guesswork. Of these three types of saws, it is the closest to being a precision tool- but only when it is properly tuned. They almost never are. One problem is the blade will have a very slight wobble to it, leaving the sawn edge rough with visible saw marks. You have to leave a little extra wood on so you can plane off the saw marks and bring the wood to the right size.

The circular saw is a medium between the table and the handsaw. It gives the speed of the table saw, but not the built in accuracy. I have never been great a cutting a freehand straight line with the circular saw, and I only really make it work when I set up a fence. In this case, a fence is usually a straight board clamped onto the wood I want to cut for the purpose of guiding the saw. The outer edge of the base plate of the saw rides against he fence. For this reason, the fence is not put on the cutting line, but is offset from it. How much it is offset is dependent on how far the edge of the base plate is from the blade, (mine is an inch and a quarter or and inch nd three eighths) and on what side of the cutting line I place the fence. Let me explain.

If you have a circular saw, unplug it, turn it upside down and pull back the guard. Measure the thickness of the blade. Usually, it will be an eighth of an inch thick. That means that, with every cut, a piece of wood as long as the cut, as deep as the thickness of the wood and an eighth of an inch wide is obliterated. This channel of obliterated wood (called the "kerf" if you want the technical term) is not to be overlooked. In practical terms, it means that when you place the fence, always make sure that the kerf will be on the waste side of the cut, not on the good side. For my saw, if I am setting up the fence on the good side of the line, the fence is to be an inch and a quarter from the line. If the fence is on the waste side, an inch and three eighths. As I said about the table saw, leave a little room for planing.

Handsaws come in many, many forms, but the two most common in our part of the world are rip and crosscut. Rip is for cutting along the grain, crosscut for across the grain. These two types of saws have radically different teeth to make them better able to perform their function. However, there is a reason why I didn't specify what kind of saw you need for this project when I listed the tools: Rip can cut across, and crosscuts can rip. They're just better at their designed function. I don't recommend using one for the other's purpose, but it can be done if you are a one saw kind of guy at the moment. You can make the cuts with one saw, but go and get another one as soon as possible. As I said earlier, getting an old one and tuning it up is an excellent way to get to know your tools.

There are quite a few ways to cut this piece out. My preferred method would have been to strike the cross cut line with a knife, deepen the line on the waste side a little with a chisel, set the piece on my bench hook, and then use a back saw to ride that groove to the bottom. But you may not have a bench, let alone a bench hook, or a back saw. So I used my rip and cross cuts. You don't need a bench for those. If you have an old chair and knees, you can make the cuts.

There are three things I want to point out about cutting with the hand saws. The first is the angle the blade makes with the wood. Think of two parallel lines an inch apart. These represent the thickness of the wood. Now think of another line representing one possible saw angle intersecting the first two lines at a right angle. Now think of a fourth line representing another saw angle intersecting the two parallel lines at a forty five degree angle. The first saw blade, held at a right angle to the wood, will be cutting away at an inch of wood with every stroke, whereas the other blade with be cutting away an inch and a half. As a result, the first angle will cut faster and the second one will be slower. However, the first angle will tend to wander off the line more, and the second, because the lower angle allows you to line up the saw with the cutting line, will be more straighter and more accurate. So which angle is best? Well, each angle has its usage. If you have time to practice, practice at every angle you can, and get a feel for the tool in wood. For now, I would recommend the lower angle.

Second, when crosscutting: as you near the end of the cut, the weight of the piece of wood being cut off will tend to break and fall off before you can finish. Whether the break extends out from the good piece or into the good piece is anybody's guess. So either support the piece of wood yourself (usually by doing an imitation of a pretzel), or have someone hold the wood up while you cut it (kids are good for this) or, assuming you have to make both a rip and a cross cut as I did, make the cross cut first and arrange it so that, if the wood should randomly break free, the break will occur in the part of the wood that will be removed by the rip cut.

Thirdly, crosscuts often cause this:

It's called tearout, and it can wreck a good piece of wood. It happens with both hand and power tools. It happens when the saw is tearing through unsupported wood fibres. It's even worse when you use plywood. It's also pretty bad when you use a rip saw to cross cut. It can be avoided in a few ways: One, use a sacrificial piece. Clamp another piece to your good piece of wood under the cut line before you make the cut. The sacrificial piece will support your piece and get tear out instead. Another option is to put masking tape along the underside of the piece directly under the cutting line. It can reduce tearout to a fraction.

I then planed the board a bit to clean it up and make it nice and smooth before the next step. I'll discuss this a little more and get to the mext step in the next post.

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