Just because you can, that doesn’t always mean you should…

So now I had a machine that could, to paraphrase Neil Gershenfeld, “make almost anything". I designed and built some pretty neat projects that made sensible use of this powerful technology, but I would also occasionally fall into the Law of the Instrument trap. This caught me when someone at ShopBot asked if I could design a plywood Adirondack chair.

It didn’t matter that they could have bought a perfectly serviceable Adirondack chairs made from solid lumber for not much more than $100 back then…I had a make-anything machine and I was determined to make everything.

In my defense I think I designed a better looking chair that they could have bought for cheap, especially the shape and tilt of the back. In my excitement to be “clever” though I broke two very important rules:

• Plywood is an amazing material with lots of sensible uses, but outdoor furniture is not one of them. Even REALLY expensive marine plywood still needs to have every exposed edge thoroughly sealed, to keep out every bit of water. After years of building boats I certainly knew that, and the chair I designed had WAY more exposed raw edges than any boat. Even with meticulous painting and sealing, water will always find a way to get in. Especially because of rule #2
• Don’t ever, ever, ever, ever, ever fasten two pieces together by driving a screw into the edge of a piece of plywood. Ever. The joint will be weak, the plywood will split, and water will get it. Just don’t do it. Ever.

You may wonder why I don’t have any pictures of these chairs. A dozen or so were built and they were actually pretty darn comfortable, but they were doomed from the day they first went outside. I should have known better, but the desire to be “clever” is awfully strong!