From wood-power to sun-power
Last summer (2015), when I knew I would be leaving my woodland workshop, I realised that I would have to do something about a means of drying chair components without using the wood-fired dryer that we had used for the last ten years. Over the winter, when making a few chairs myself or when providing some personal tuition, I have always been able to dry bits of wood, either in our wood-fired cooker in the kitchen, or in a rack above the living-room wood-burner. If I’m going to have four people at a time during the summer then I am going to need some other method. Having recently had 11 solar panels fitted to the roof of my workshop, it now made sense to use electricity to power the drying system during the summer.
Good news and bad news
A couple of years ago I inherited an elegant wooden cupboard with sliding shelves about 50cm deep, much the same depth as the woodland drying unit.
I sat it on my workshop bench, surrounded it with foam insulation and placed a fan-heater inside. With some freshly made chair rungs inside the cabinet, I left the fan heater running all night. By morning, the wood was nice and dry but……………. the fan-heater had burned out. Neither finances, nor environmental considerations nor indeed fire safety, would allow me to continue like this.
I have spent my 30-year career working on the principle that if I can do it, so can anybody else. I have purchased specialist tools but I have always tried to cobble together all the other equipment myself without any specialist input, other than equally unqualified volunteers. However, I had recently met John Lane, a heating engineer who had fitted a system for Ben Orford and he reckoned he could work out a system for my workshop. He was keen to attend one of my courses so we arranged a skills exchange. If we somehow placed a fan-heater outside the drying unit, it should be able to run for a long time without overheating. I contemplated making a special plywood box but the antique cupboard was so well made and nobody else in my family wanted it. Rather than throw it the tip or burn it, I felt happy to adapt it for a drying cabinet.
Warm air circulation
John duly took a load of measurements and returned several weeks later with all the components made up and ready to fit. He sawed a couple of square holes in the cupboard and fitted an adjustable metal manifold to the hole in the top and a shorter piece in the hole in the bottom.
With the cabinet upside-down, he fitted some more tubing which had been fitted to both ends of an electric fan-heater.
The idea is that the heater blows warm air into the bottom of the cabinet and after circulating around the inside it passes out of the top corner and down the manifold, back to the fan-heater to start again. With lots of foam slabs held in place on the outside of the whole affair by some sticky foil tape, we lifted it back onto the space, where my bench had been.
This will work best with just one shelf inside, which allows the air to circulate through twenty or so large holes drilled through the base of the shelf. I have placed a metal grid a couple of inches above the shelf onto which the drying components can be placed. The steam bent legs will sit in the lower half, still clamped onto the bending jigs. (The clamps should fit quite happily). We ran the heater for an hour or so reaching about 50 degrees centigrade. With the woodland dryer we aimed for about 80 degrees but I’m hoping with the air circulation it can operate at a lower temperature but still dry things out within a day.
Watch this space!
During the recent dry, almost spring-like weather, I have been catching up with jobs in the garden preparing for the erection of the new shelter (the tarpaulin arrived yesterday). The acid test for the dryer will come next week, when I have two staff from the Ruskin Mill organisation coming to make a couple of spindle-back chairs between Monday and Friday. As always, we shall be using ash wood, some from the 64-year old ash tree that I used in December and some from a freshly felled tree, kindly given to me from a local Woodland Trust Millenium wood, only 16 years old. I shall do my best to report the progress on this blog.