Light Aircraft Association

Hi!

I'm planning on building a Druine Turbulent (still awaiting the paperwork to register the project). The plans use imperial plywood measurements and metric wood measurements, and SWG for metal fittings.

I was wondering if an official document exists that spells out accepted equivalences for imperial vs metric material , in particular plywood? Do people simply use the closest metric plywood thickness, or is it generally rounded up? Or rounded down?

While on the topic of wood, I would appreciate recommendations for places to buy aircraft grade spruce and plywood. Any suggestions? I would ideally prefer to have a somewhat local supplier, as I intend to buy material as I go along, and am trying to avoid getting stung too much on post and packaging.

Many thanks!

AA

There was a suggestion in the PFA mag many years ago, when plans built aircraft (wood and plywood) was the norm, which stated that manufacturers of bespoke wooden ladders had supplies of spruce that matched aircraft quality material due its very straight grain and level of “dryness”.

I don't know where you are, so what counts as local, but this mast-maker near Oxford can get suitable spruce: http://www.collars.co.uk/