The bits that constitute my ’51 Flying Squirrel include two gearboxes that came with the sorry pile. As neither have a foot change it would seem pretty obvious that these boxes do not belong.
One box has a 23/20 – 17/26 – 20/23 cluster the other a 19/24 – 14/29 – 25/18 cluster. The only identification is a “150W” stamped on one and “15M” on the other, would anyone care to speculate a date and original model for these boxes?
A point worth noting about these gearboxes that I’ve not seen mentioned elsewhere is that there is a difference of 0.015″ between the mainshaft/layshaft centres. While 1/64th might not seem to be a lot anybody contemplating a bit of cog swapping might care to bear this difference in mind as while it might be possible to assemble a box with a ‘wrong’ set which might even seem to turn smoothly the rolling action of the involute tooth form will be seriously compromised.
And has anybody guessed what comes next? Yup! You’re right; I’m in the market for a gearbox for a 1951 Flying Squirrel!