Wobbly

Well the whole notion of a “balance” pin (or two) just wasn’t working out so I went with a flange-and-pin joint like everywhere else.  Unfortunately, because of all the drilling and holes I’d put into things, and due to a bit of short-sightedness, this flange joint is currently only one-sided.  And so the key lever (that long part sticking out at the bottom of the picture below) has a lot of side-to-side play.  Not good — don’t want the lever to drift off-line and get two notes for the price of one!

Wobbly Assembly

There are quite a few flaws in this design that I’m still ironing out, but I think one good principle I’ve centered on is this: any time there’s a hinge, construct it solely out of 1/8″ plywood.  This stuff is pre-milled and consistent and I can plan for that consistency.  I’ve been cutting tenons into thicker (3/8″) pieces to create 1/8-inch “tongues”, but they’ve ended up too inconsistent in size and I’ve had to spend time grinding them down to get them to fit.  The result is that they’re then a little too small, or wedge-shaped, and just have too much play.

I’m already looking forward to a complete do-over starting with fresh wood, but I do need to see this prototype through so I can iron out any subsequent problems in the parts I’ve haven’t even installed yet…