The wonders of aviation ply
During Dorset Art weeks, back in May, I saw some lovely wastepaper bins made in very thin birch ply. I’d long hankered after some of this ply to make lampshades like those by David Trubridge, having experimented with laser cutting at the Keighley FabLab. But I couldn’t find any local stockists and it’s not the kind of stuff you can really order over the internet, as it costs a fortune to deliver a large sheet or even a roll.
After seeing the simple-but-stunning birch ply designs produced by Cameron and Talbot in Dorset I renewed my efforts to track down the plywood. A few phone calls to importers (it all comes from Finland and the Baltic states) revealed that the really thin, bendy-but-surprisingly-strong ply is generally called aviation ply. While it is more often used to build model aeroplanes nowadays, there are still mad people who make full-sized planes out of it in their sheds.
Finding a local supplier of the higher grade aviation ply took some time. Mostly this stuff is used by shopfitters who don’t care too much about surface defects because it will be painted or veneered. But the kind sales director of a big timber importer steered me towards James Lathams on the outskirts of Leeds. The Lathams warehouse is vast and not really geared up for one-off sales to private individuals, but the office staff were very welcoming and helpful. They sell “BB” quality (the second to best), 1.5mm thick ply in 5ft by 5ft sheets at a reasonable price. A sheet rolled up tightly enough to fit in the car, but unfortunately it didn’t leave room for dear husband who was with me at the time. I did suggest he might like to go home by bus and train, but he wasn’t keen on the idea. So I must return, solo, to pick up the aviation ply.
In the meantime, I’ve been designing bins and making models out of paper to test the proportions and decide what size looks best. This has involved using drawing tools I haven’t used since I was a newly-graduated engineer (adjustable square, protractor, curve-drawer, compasses), and a fair bit of head-scratching to work out the 3-D geometry. (To all those people who maintain that trigonometry is of no use once you leave school: you’re wrong.) Then I transferred my designs to Google Sketchup and cursed a lot as I struggled to make it do what I wanted. Sketchup is an immensely powerful modelling package with a relatively gentle learning curve, but I just don’t use it enough to be totally familiar with the commands. I have ended up with variations on a fairly simple shape as shown in the photo. I may yet add a decorative design of cut-outs or etching.
Within the limitations of the laser at Keighley – working area 24″ x 12″ – I will be able to make a wastepaper bin of standard size. This shape could be used to make a bin out of any sheet material that will flex but has enough stiffness to hold its shape, like polypropylene, hide leather or industrial felt. I need to decide how to fasten the two overlapping sections together at each side. Rather than glueing, I fancy drilling holes and then lacing them up with wire or leather. Small brass bolts and nuts might look good too. Somewhere out there, there must be some stylish industrial fasteners in stainless steel or black nylon that would do the job, but I have yet to find them. I feel a visit to Clas Ohlson coming on…
Electric Eel Wheel update
Another project that I’m working on is the Electric Eel Wheel spinning machine. I have at last taken the plunge and ordered a DC motor from Ebay. It arrived this morning, which is very exciting. The next step is to get to grips with Arduino, and with Eagle, the programme that the designer has used for the motor controller’s printed circuit board. I’d be tempted just to buy a motor controller, but I don’t know enough about them to choose an appropriate one. And I’ve been meaning to get into Arduino for some time, this is a good opportunity.
What’s happening on the gansey?
I have neglected my gansey recently while I knitted other things. But I have now picked up the stitches around the second armhole and am about 6″ down the sleeve. The end is definitely in sight. I’ve set myself a target to complete it by the end of Propagansey, the annual gansey exhibition in Robin Hood’s Bay. That gives me just over a month, until 20th September. I’m not at all sure I’ll get to Propagansey, but if I do, I want to have something self-made and impressive to wear. The alternative is I wear it unfinished, put one arm in a sling and pretend I have broken it.