Looking for dimensions/Drummond gear change fork

I'm after a bit of info if anyone has one, i need a few dimensions from the gear fork of a little drummond, to help get this lathe running again, my intension is to make a 3d printed version as a mock up to prove, then maybe make a 2part piece from 2 bits of ali, round stock and a bit of plate. Made a quick sketch on freecad. Proberbly a bit much but here is hoping, thanks in advance.

I need:

the angle between the forks

the length of the slots

A rough distance of the start of the slots from the center of the fixing boss

The distance of where the shoulder bolt/gear bolts are in relation to its mounting boss machined face on lathe bed. Seems to be inline with the recess around the boss.

Is it the banjo you mean?

(Perhaps a mod would change the title)

If it's a roundbed I could perhapse help. I do have one in bit's.

regards Martin

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From Chris’s album photos … it would appear not

MichaelG.

Think this is for the OP's Type B?

Er, Ady, (and others?), do you think the M type (or any other Drmd. fitment) might be the same?

Edited By DiogenesII on 23/10/2021 11:17:39

Edited By DiogenesII on 23/10/2021 11:20:41

My answer is probably

but needs to be checked

My lathe boss is 1.75" outer diameter

Yes the banjo, last photos didn't upload so reuploaded.

Its the one with the screw feed at the front, still unsure of the model

Round bed Pre B, Btype and M are all different. Your best bet is to keep an eye out for a donor lathe .

This is how I ended up with 6 1/2 B types but in the end it is an economical way of stocking up on spares .

theres a healthy market for anything you don't need.

Round bed , Pre B, Btype and M are all different. Your best bet is to keep an eye out for a donor lathe .

This is how I ended up with 6 1/2 B types but in the end it is an economical way of stocking up on spares .

theres a healthy market for anything you don't need.

Chris, if you haven't seen this page, it's worth a look in detail, particularly the photo about 3/4 of the way down whose caption begins 'Instead of a single slot L-shaped...' & which shows a compound reduction train for fine feed, which is likley to take up as much 'banjo-room' as you are likely to need - it's common to put one's largest wheel on the leadscrew, leaving the next largest pair and the next smallest pair to be compounded into two sets to fill the gap between the spindle and that - as the 'top' pair will be on the 'main leg' of your banjo, the length and angle of the lower slot will constrained quite narrowly by the need to mesh these to the leadscrew gear..

It's a rather complicated thing to describe, I hope the pictures help explain it better.. I notice that the ends of the banjo are shown in the picture, you may be able to approximate the lengths and angle by experimenting with cardboard templates or by drawing them up..

Lathes.co.uk - Drummond B-Type Lathe..