Thread: 9A Gearbox Reassembly Dramas

Hi everyone,

I haven't had much time lately, but I did attempt to reassemble my 9A gearbox. I had a problem when I came to fit the centre shaft with all the gears on it.

Basically I couldn't get it through the gears and back into position in the casing - the gears are very tight on the shaft. (It was very tight when I disassembled it too.) So I hit it with a hammer to drive it in. Only a small one, but I probably shouldn't have done that. I still couldn't get it together so I pulled it out again and tried to fit it without the gears. Now the end that I hit (the big end) won't go all the way into its bearing - stops about 3mm out and jams. I guess I've deformed the end of it such that it no longer fits.

The plan now is to finish cleaning and reassemble the lathe - without gearbox or leadscrew - then take a very light cut at the end of the shaft to reduce the diameter so that it fits again. I then have the problem of making it all go back together with the very tight gears. Once the lathe is running I think I'll make up a brass guide for the small end to keep it aligned, and a brass drift for the big end so I hopefully don't damage that end again.

Any clues or suggestions from anyone?

Thanks,
Ant