Does this page from the Wayback Machine help? Warco BH600 (No G but could that mean gap bed, which this machine has).

Brian G

Spindle bore is 5MT (There should be a sleeve to reduce to 3MT with the machine. Throughway is 38mm from memory.

METRIC THREADS

6, 3, 1.5, 0.75 with standard 40T Idler driver, 40T gearbox

with 40T Idler 32T, 7.5,3.75, 6, 3,1.5, 0.75, and 5,2.5,1.25

IMPERIAL THREADS 40T 120/127 40T

DOUBLES the tpi as you go through positions A through to E on one handle.

Position 1: 4,8,16,32,64, Position 2: 4.5, etc Position 3: 4.75 etc Position 4: 5 etc Position 5: 5.5 etc

Position 6: 6 etc Position 7: 6.5 etc Position 8: 7 etc on the other handle

So from 4 to 112 tpi.

No doubt if you play tunes on the possible combinations, of meshes of the 40T, 32T and the 120/127 Idler you can find other pitches or tpi that are useable, plus MANY oddball non standard ones.

Howard