Several years back a couple of mates & I bought 3 Harrison M250’s out of a school auction, the other two sold theirs’ on, but I stored mine ( code for stuck it in the garage behind an old Drummond, piles of dismantled Merc engines, Mini bits, tractor rams & general useful stuff).
Bringing it into operation this year, I found that, while the 3-jaw chuck & catchplate were both D1-3 & were fine, the 200mm Elliot 4-Jaw in the lathe cabinet was a D1-4 Blast! Double Blast!
Hence my question:- Since I can find a 125mm D1-3 backplate for £50-60, would it be feasible to bore out the Elliot chuck to fit a suitably reduced D1-3 backplate & bolt the two together? I have a Kerry lathe plus a Marlow mill available for the job. Has anyone accomplished such a task &/or what are the flaws in this proposal? Is there an easier way of converting D1-4 down to D1-3?