Hi Bill,

Those pictures were really helpful in concreting JohnS' thinking. That doesnt look so hard to make either, though how do you make a small (say 5mm dia max) tapered hole. A 3 - 14mm HSS taper drill is about a tenner on Amazon (although these are supposedly only for drilling sheet). Machining a taper on a bit of 6mm silver steel rod shouldnt be hard - tho I'd imagine these might need hardening after?. The T-slot in the table is 6mm wide I think, so some 12mm silver steel rod would do for the pins (again do I need to harden after)? Then I need a 100mm cast iron plain backplate, or a 12mm thick bit of 100mm dia mild steel?? I suppose it has to be steel?