Ok, since I said I was recycling, I was running through my stock of plywood odds and ends. The biggest suitable piece I found came from a wardrobe, and is very definitely older than I am. The downside of this recycling is that the Nitromors had to come out to remove the layers of varnish applied at least 50 years ago.
Construction was in stages:
Stage one, cut out the platter, sides and rear piece based on the template and any notes scribbled there upon.
These were stuck together using mitre bond. This is medium cyano with kicker, intended for picture framing people. Seems to work rather nicely on model airplanes too. Other bits n bobs were cut out as required and stuck in place, resulting in this:
You can just make out the 'magic' pieces under the tray top. Here's a closer look:
These are more blocks of scrap ply from some project or another salvaged/sacrificed for the greater good. The centres were marked and then drilled with a 5 mm drill bit.
These blocks of ply were then firmly fitted into a bench vice and tapped, using an M6 tap, to mate with standard (long) M6 wing bolts. The M6 bolts were epoxied and pinned into the arms so they can be removed later.
The key to tapping plywood is runny cyano. After the thread has been (carefully) cut, soak the thread liberally in runny cyano and forget about it for a while. When the cyano has set (this can take a while, longer than you might think) clear the threads using the tap. Voila, an M6 'nut' of plywood. This works for many screw sizes, the only gotcha is that it works best if the mating bolt is nylon, rather than steel.
Here's a closer look. If you look carefully the threads are visible in the plywood.
There we go, I need to tidy up a few little things, fill a few holes (from its former life as a wardrobe) and finish to look neat, but its perfectly usable in its current state now.
Probably 3 - 4 hours in total to get to this stage. The biggest delay was stripping the old varnish off the recycled ply.
Job done (almost). Pressure off now, need to transfer some model settings to new tranny and then its time to test it all out.
