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.