Thursday, January 24, 2013

Mirrors



I completed the other chair today. Both the offspring seemed pleased with their lot and the seats seem to make a happy pair. I like the fact that they are made from the same log and the same old car spring. The plank that the seats came from was cut across the middle and if you placed the front edges facing each other you could trace the grain across from one to the other. The grain in the backs is very close to a mirror image with the main heart of the tree running through the pad shaped arm.
Counting the rings showed that the tree had been around for more than 75 years at the height where these pieces were cut, but judging from the size of the rotted branch in the section of wood that I cut up to make these it must have been quite a few meters off the ground, so the tree may have been around for as many as a hundred years before it was cut down.
Come February the chipping machine will visit the stockyard and the mountains of wood there will be turned into mountains of chips, it is nice to have been able to pull these bits from the maw so that they can remain in the world in this shape for a while longer. Increasingly I feel the sense of responsibility in undertaking the task of making objects as the awareness of my own age and mortality make it more obvious that these objects will still be around when I am not.
Fortunately there are amusing nuances to the process that prevent us from lingering on the nature of numbers for too long. In this case as with some other individuals among the Zelkova species that I have encountered in the past there was a tendency to pong when fresh cut, this chap's severed bits left the piquant pooh smell lingering in the living room for a while. That caused some suspicious glances to be exchanged, thankfully the fragrance is fading fast.

Sunday, January 20, 2013

Birthday



A tough day getting one of the chairs finished up. From welding up the struts to here was quite a lot of work, after this first clamp up stage I attached the struts to the back rest with three 8mm threaded inserts and some Allen socket head bolts.
Then I welded 12mm nuts onto the bottom surface of the three strut plates and drilled out recesses for those to sit in and then drilled holes for bolts to be passed through the seat up into the nuts. This structural work is similar to the chair made in October, but the wood for that was fairly well seasoned. The wood for these chairs is almost completely green, cut into planks only days ago. This means that it will move a lot while in use. That is why I chose to use three separate struts rather than bars stemming from a single plate. Each of the struts should be able to flex and shift as shrinkage occurs across the board of the seat and the back rest contracts. I shall be keeping an eye on them as time passes.
With the welding done I did some final shaping on the seat and back and then set to scorching and polishing. The ironwork finishing was the last job. I had run out of the tea and tool steel mix I use to blacken the steel, so I collected some tea leaves from the bushes next door and mixed them with the filings I collected while sawing the disks from the big bar and boiled it all up for a while. This creates a satisfyingly inky black liquid. With the iron heated this mix is brushed on and blackens up the oxide coating on the steel. Then a mixture of wax and graphite powder is applied while the steel is still warm. You have to take care when heating the steel as too much heat will cause the oxide layer to prickle and crack off. The final result is as below. The photo above is a bit of a cheat as it is from the next chair. I was too busy getting the job done to take pictures. I use a variety of disks in a grinder to polish the wood after scorching and wire brushing. I use a speed controller to keep the grinder from biting in and friction from melting the scouring pad type coating on some of the disks.


Iron work



This little patch of workspace is within the maw of the fly press. The six bars here are on their way to becoming the struts for the chair backrests. All are worked from a set of springs that must have come from the suspension of a large car. I found them by the side of the road some years ago. The ends of four of the bars have been flared out while two are still to be done. They have a blob shape of upset metal on the end to allow the flaring to be a little wider than it would by just fulling out the bar. There are two disk shapes here that will be the plates to join the struts to the wood. The disks were cut on a bandsaw from a bar of tool steel. The same bar that most of my press tools were made from. One disk is still just a blank that has been floor annealed (brought to a bright orange heat and left to cool). The other has been worked in the press to give it some texture and shape. In normal steel the little depressions around the edge of the disk could be done in one or two strikes, but the tool steel took five strikes on each due to its added toughness.

Saturday, January 19, 2013

Butchers



A couple of years ago I was offered the use of some standing trees in a kind of car park open space. We had a big snowfall last Monday, so my other sources of supply are a little damp or inaccessible and we are running low on firewood. Friday I went to fell two of the trees and picked ones that had a nice leaning bias into the open space rather than out onto the neighbouring road and power lines. I cut up and carried some home yesterday and then went back with my daughter today to get the rest. It was interesting to see them laid out horizontal against the white and then see all the sawed up segments of the main trunks and branches before they gradually disappeared as we loaded them into the truck and hauled them all home. All very scientific looking.This would be a devil of a job without the chainsaw.
The fate of the remaining three sisters is sealed, but I would like to use at least some of the wood rather than sending it straight back up the chimney into the carbon cycle.

Wednesday, January 16, 2013

Tacking



I scorched and polished one of the back rests. There is one of the off cuts from the slabs under it here to get an idea of height. The other set of legs is on the table behind. I marked a circle on a sheet of steel and then marked points on it 72 degrees apart to indicate where the five small sections of pipe that house the rods for the casters would go. Then I tack welded those onto the sheet and drew chalk lines for the central hub and legs. I put a little support piece under the center and cut the lower rank of bent square pipe pieces to shape and tacked them onto each other and the little fringe of caster holders. Next I tacked in the hub and finally cut the top rank of leg struts.
There is still a lot to do.

Tuesday, January 15, 2013

Backs



The wider of the two planks I cut was about 53cm and that was about what I wanted for the seats. That would be the length of the flat side at the top in this picture. I misjudged the center a little so the loops of annual rings were off to one side as you might be able to asses from the shot. This is the remnant from the end of the log that I then cut two slabs from about 12cm thick for the backs. The fact that the two seat pieces when cut from the plank would have a left right asymmetry put me in mind of the fact that my daughter is right handed while my son is left handed. This was then reinforced by the two whorls of a fork in the young tree off to the right in the picture. I changed my plan a little and made one side of each back into a rounded pad to rest a cup on.

These are the two back rests I cut from the slabs, I think the cup rest should go on the other side from the preferred hand, but I guess they can swap seats if the reverse proves to be more comfortable.

Saturday, January 05, 2013

Yesterday



Time tunnelling, it is actually the 15th, but I am post dating to document the seat construction. The eye injuries from the end and beginning of the year are pretty much healed now. I cut two planks off of the chunk of trunk that had been left in a clump of bamboo right at the bottom of the dam wood yard as mentioned in yesterday's post. I didn't think it was worth trying to shift the thing to get a better work position, so I was basically scrabbling about on the ground as usual to manhandle the chainsaw through its course. Nailed on one batten up at the top end of the log and then sighted up from the other end to nail on the other batten. The two rails are then laid on those battens and the chainsaw guide runs on them. The underside of the log had a huge rotted branch in it, so I used one end of the remainder by cross cutting two diagonal slabs that will form the back rests of the chairs. Meanwhile sammy worked away at the woodpile to cut up logs for two truck loads of firewood. We left a few pieces from this log as the truck had worked pretty hard and we didn't want to break its back with a few straws more. Hopefully pick them up some day soon.

Friday, January 04, 2013

Peace



Sometimes I really get a strong urge to draw someone, and several times recently when that has happened I have found all the inmates involved in activities facing the wall. I don't think they are consciously avoiding the vulnerability of being put on paper, but somehow just not in model mode. Today fortunately sammy decided to grate some potatoes while sitting on the floor next to the stove, so five minutes of fun for me with a little pen and a water filled brush.
We had a good three hour session at the stock yard gathering firewood and I spent a good part of that firing up the big chainsaw with the guide attached to make some planks out of a lump of Zelkova. I am hoping the planks will form the seats for a couple of chairs for the offspring.