Tuesday, September 23, 2008

High Speed

Here is a short video that I made while turning the staircase balusters. I sped up the video (I'll post the real time version next) to show how the baluster takes shape in stages.

I try to group tasks so that the piece retains mass, which helps reduce vibration, and to change tools less frequently. Also, by having intermediate steps, I repeat tasks, such as turning all the beads at once, or roughing out, without having to constantly change my focus. All these things help make a complex turning more simple.




Watching this in fast motion makes it look way too effortless. Believe me, turning dried red oak like this took all the concentration I could muster!

Thursday, September 18, 2008

Announcements

The days are getting shorter and the nights colder here in New York. Now I am stacking firewood and thinking about next year.

I will be teaching at a few schools other than the individual classes at my workshop. In March, I will be teaching a 5 day class at Arrowmont in Tennessee. Noted wood sculptor Brent Skidmore will be a visiting artist in the class.

In August, I will be helping Curtis Buchanan teach a 2 week class at the Center for Furniture Craftsmanship in Maine. Curtis and I have a lot of fun when we teach together and this would be a great opportunity to experience a lot of different techniques. We may also be together at another school but the details are still to be worked out.

I am happy to say that the first of the independent reviews of my caliper is out. The review, written by Betty Scarpino (who is the new editor of American Woodturner) can be seen at

Woodworkers Journal Ezine

Now I gotta go light a fire in the shop, aargh!

Monday, September 15, 2008

Game Plan

I recently began a project turning some balusters for a friend who is renovating an old house. The original chestnut balusters are spaced too far apart for safety with small children. I did a similar job in my own house and enjoyed turning something besides chair legs.

These turnings offered a perfect opportunity to show something that I've been meaning to post about for a good while. Creating a process for turning parts is one of the most essential components to making a successful turning. When I began learning to turn, I started making shapes at one end and worked my way down the length of the piece, finishing off each shape as I went. This not only creates a lot of wasted motion constantly exchanging tools, but ignores the problem of vibration that can be avoided by better sequencing. It can also be more difficult to shape the various beads and coves without having the shape that comes next to it defined. Let's face it, learning to make the shapes is hard enough without the confusion thrown into the mix!

For this baluster, I made 3 separate patterns. The first one defines the largest diameters and the different areas that will get more details later. The second one notes the final depth cuts that will be used and the last one has all of the measurements that I need to finish it off. By having 3 distinct steps, the whole turning process flows.

Below are a few balusters in different phases. The one on the left is simply the transition from the square to round. The second one over is the first pattern complete. From this blob of a turning, the final one (on the right)is surprisingly close.



In the image below, you can see the parts formed in the initial turning. I chose them because they defined the major or most easily confused elements. I also chose them because they could be roughed out with a single gouge. After this stage, I move on to the final cuts. By leaving these thin areas for last, I greatly reduce the vibration. Imagine leaving only 3/4 inch in one area and then trying to rough out shapes next to it. A recipe for vibration.

Once I move on to the final cutting, I always start finishing in the middle of the piece. This leaves more material near the ends and helps reduce vibration. The areas near the head and tail stock tend to vibrate less anyway, so working the middle first has always made sense to me.



It did take me a little head scratching to break this turning into a series of patterns and then into steps within the patterns. But within turning only a few of them, I was able to recognize where I was in the turnings and know what step was next. It's a fun challenge, but turning this dry red oak reminds me of the reason that I became a green woodworker!

As an aside, I am matching the old chestnut (shown on the far right of the top photo) by painting the red oak with a very thin coat of orange milk paint, then staining the piece with a thin chestnut stain, and finishing it off with orange shellac. I think that I am close enough to the old (rather sloppily finished) balusters to fool the 4 year old that will be seeing them up close.

Thursday, September 11, 2008

Square?

It's been years since I chopped my last "square" mortise, as opposed to the round ones that I use all the time in my chairs. Chopping a mortise with a chisel defies the imagination. It seems like it would be nearly impossible to chop a mortise that would be uniform in width and depth, not to mention going straight into the wood. But I'm happy to report that it isn't that hard at all. Of course a little practice doesn't hurt, but the key lies in using a chisel the exact width of the mortise and orienting the workpiece so that the mortise is vertical.



I use the wooden clamp to hold the post in place. The flat on the front of the post registers against the flat on the jaws and insures that the mortise is vertical. Another clamp hold the wooden clamp tight to the bench. You can see the initial chops that I made to establish the mortise. Once these chips are cleared, I repeat the pattern only deeper. It's important to have the bevel opposite where the chip is forming. That way, the natural tendency of the chisel to shift away from the bevel will help free the chip.





Here you can see the mortise after being dug deeper. The chisel on the benchtop is an old chisel that I reground at 90 degrees to the original bevel, so that it would be thinner than my 1/4" mortise. I use this to clear the chips and level the bottom of the mortise without affecting the sides.



Here I am marking the crest to locate the shoulder of the tenon. Obviously, hand chopping mortises like this is no way to do "production" work. But in this case, where I have 2 mortises per chair, it's 20 minutes of careful handwork that I enjoy, not to mention that improving my dexterity with the chisel can't hurt.

Monday, September 8, 2008

Chair in Motion

There is only so much that can be conveyed in still images. In this most recent rocker, I was striving to create motion, in both the lines of the chair, but also in the actual wood. Folks who have tried it out have all commented on the gentle "give" of the back. I have wanted to build a chair that had the flex of a combback, but without the arm passing across the back.

The ability to match the curve of the back is only part of the challenge. If the chair works only in a single position, the sitter will soon become fatigued and need to shift. I found that the added dimension of flexibility can help create comfort while the sitter takes on a number of positions, because the weight distribution of the sitter actually reforms the shape of the chair. It may sound obvious, cushioned chairs do it all the time (often with too much "give"), but we're talking about a wooden chair here, and by using split wood, shaved along the fiberline, I think that the challenge of making a "hard" chair "soft" is met.


Thursday, September 4, 2008

Results

Here is the new rocker fully assembled and ready to fume. I am sure that you'll recognize many of my influences in it.



Here it is after a couple of days in the fuming chamber (shown below) with some janitorial strength ammonia. I should say that anyone attempting this should be careful to avoid the fumes. I did this by hoisting the cover up to the roof of my barn with a pulley while standing away from the area. This way the fumes could dissipate safely.



I removed the chair from the chamber and oiled it, only to realize that I wanted it darker, so I put it back in the chamber and the color continued to shift despite the oil. I am very pleased at the way that the oak and the butternut changed colors so similarly. It looks like the whole chair is made from one type of wood.



This shot shows the thin spindles. They have just enough give.



One of the most lovely qualities of the fuming is the way in which it accentuates the rays. I oriented the crest and spindles to show this. I like the way that it looks like a scribbled drawing that catches the light. I guess that there is still a painter in me somewhere.



Here is the chamber that I built. It is a simple box made from 1"X 2" and 2"X 2" lumber covered with plastic. I cut a hole in the plastic about 3 inches square and covered it with clear packing tape to create a window so that I could judge the progress.



I am looking forward to playing so more with this method of coloring the wood. The clarity of the grain (especially in the seat), and the deep colors add a lot.

Wednesday, September 3, 2008

Staying Flexible

As I set out to design my recent rocker, I did my best to refine and refresh my goals as a chairmaker. It's easy to get caught in preconceptions and force of habit, so staying flexible has become a primary goal.

One of the parts of chairmaking that I love is shaving wood at the shavehorse. Sitting quietly as I follow the fibers and form shapes is a real joy. My recent rodbacks have fulfilled a great deal of my aesthetic curiousities, but have pulled me too far from the shavehorse (and towards the lathe).

The shaving is also the key to unlocking the amazing strength and flexibility of the wood. It seemed like focussing myself back at the shavehorse might be fun as well as an asset to the comfort of the chair.

I spent a lot of time looking at other chairs of many styles, and found myself captivated by the ladderbacks that I saw in John Alexander's book Make a Chair From a Tree.

In his book, John shows how far a chair can be trimmed down to essentials. For instance, his slats are less than a quarter of an inch thick! Well, that got me thinking.
So this recent chair is all about flexible wood.

As you'll see, many of the elements of the ladderback have found their way into this piece. Below is the joint where the crest and stiles come together. I have borrowed the square mortise (boy is that fun to chop) and the square pegs. I also found that the relief along the front thins the stile out enough to create a lot of "give".




Here is the spindles in their rough form. They are just below 3/8ths of an inch thick. I shave, steam and bend them. Then, I form the tenon at the bottom and go about refining them.




What you see above are the arcing lines that define the locations of the details. The bottom line is where the spindle is relieved on the front and back from around 1/2 inch to 3/8ths inch. The next mark up is where the width of the spindles flares to 1 1/16 inch wide. And the top mark is where the spindles begin to taper to the 3/8 inch top. The effect is subtle but creates a more visually interesting field than keeping them all uniform and also give the widest support to the part of the spindle that bears the most weight.

I'll be showing the assembled chair soon. By forming a curved back, out of thin pieces, the top of the chair is extremely comfortable and capable of forming to the sitter, while offering good support. I think this one might even usurp my trusty continuous arm rocker as "my chair" in the living room!

Monday, September 1, 2008

Parabolic Rocking

As I got to the last part of my recent chair assembly, I decided to try a hunch and redesign my rockers. The rockers on my chairs have always been simply portions of a large circle with an area at the back that has a slightly larger radius. This flatter area at the back of the rockers acts as a brake, slowing the motion and helping it reverse. I have always felt that rockers that are simply a portion of a circle can rock back too far and make me tense.

After years of "winging it", I decided to try laying out a parabola, which naturally and fluidly flattens out toward the ends. After some tinkering with the numbers, I settled on the dimensions and layout shown below.




The layout is pretty simple (and cool!). Start with a baseline that is 38 inches long. Half way across it draw a perpendicular line that is marked at 4 1/8 inches and 8 1/4 inches off the baseline. Next draw lines from the ends of the baseline to the top mark on the perpendicular. Then mark off the sides into equal increments (the more the better). Finally, connect the lowest mark on one side to the highest on the other. Proceed up and down the sides as shown. The lines will form tangents to the parabola and give a relatively smooth curve.




Here is the final rocker, in the chair. I found that by shifting the rockers forward or back, I could place the "brake" exactly where it is most comfortable. I'd be curious to know if anyone else has worked with parabolas this way, and if so, why didn't you tell me!