[HELP] Can someone help me to re-gear my lathe?

[Pete O]

I'm far from an expert Dan, but I guess you have a number of options for speed reduction across that gear train; smaller gear on the lathe spindle (chuck shaft) (the fwd/rev tumble pair would need to still be able swing into mesh); larger gear on the big side of the compound gear; smaller gear on the small side of the compound gear; larger gear at the final driven shaft. I think I'd start by seeing if it is possible to achieve the desired reduction by rearranging the gears you already have; if not (probably not) then I'd look at the most economical place in the chain to achieve it, i.e. where the least number of new gears are needed. It looks like it might be possible to put a bigger 'big' gear on the compound set without needing to change any of the idlers, as the banjo can adjust (swing) to accommodate that? Looks like the way the banjo is made, a bigger gear at the final driven end will necessitate a new idler and unfortunately the banjo has been manufactured without a way to accommodate this.

One of the electronics wizzes on here could probably devise a way to drive the leadscrew electronically at an infinitely variable relationship to the spindle. That would be cool. Possibly end up cheaper than gears!