Screw thread chart

[robwizard]

My Viceroy is a pretty basic model, no gearbox and no power cross slide. Despite this it will suit my very basic needs and I am attempting to get it back to running order. The guy I bought it from had managed to loose pretty much everything smaller than a fist including all the gears, studs, nuts and bolts. What a guy..

Anyway I have acquired a bunch of change wheels and am attempting to construct my own chart based a photo someone showed me. Can anyone confirm if it looks correct and tallies up with a real chart?

It's a metric machine though I haven't measured the pitch on the lead screw I presume it is 3mm..?

Cheers

[rpwilson]

I've got a drawing showing the basic arrangement for a non gearbox metric lathe, type TDS 1 Metric, drg ML105/100A/M, which refers to Chart CH159 for the actual individual gears for each pitch, and I don't have a copy of that chart.
Drg 105 does differ a bit from your chart, for example in Fig 1, it uses a 100T instead of your 80T as the idler, but as its only the idler, that won't affect the outcome.
In Fig 2 it also uses a 100t as the idler, but also uses an 18T gear where you show a 16T gear. Without Chart CH159, its hard to say what difference this makes.
It doesn't seem to have an equivalent of your Fig 3, but it does have an arrangement for fine feeds and pitches 0.12 - 0.05 which goes Stud to 66T/18T to 72T/18T to screw gear.
Have a search through the drawings archived on this site, see if the chart is on there somewhere.

Hope this is some help.

Richard

[robwizard]

I have been looking through the drawings recently and can't seem to find anything, though I do recall seeing a drawing at some point. It could have been a for a gearbox model I can't really remember. The photo which I based the drawing on was good but the details of the numbers around the different figures are very hard to make out. Looking at it again I suspect that where I have a "16t" it is in fact an "18t" as you suggest. The "100t/80t" I'm not so sure about. The lathe the photo is taken from is a P/C/S model so in the photograph it also has feeds for the cross slide, though I'm not sure how these relate to the model I have. I have committed that section from the drawing as it is of no use for me. It's proving quite difficult to find any information on the model I have as most people seem to have the superior gearbox model haha.

Cheers