12-04-2016, 05:15 AM
I'm going to make some semi-educated guesses that I hope may help. There are a few controls on the apron of the lathe, presumably one of them is to engage the 'half-nuts' for threading (this uses the big acme thread on the leadscrew), one will be to engage the power feed in either longitudinal or cross feed (probably driven by a keyway in the leadscrew that operates a gear set in the apron).
Presumably there is also a moveable gear, probably at the back of the headstock, the 'sliding gear' that can either be 'in' or 'out'. The photo on the web page shows a lever on the headstock above the threading gearbox, I'll assume that is for the 'sliding gear'.
The chart on the gearbox is set out in columns which correspond to a position for the bottom selector lever directly below that column. The rows obviously refer to the position A, B or C of the lever on top of the gearbox.
The big numbers are threads-per-inch you will cut when using the half-nuts (on the apron) with the gearbox levers in each position. The small numbers are the distance the tool will move along the work when using the power feed,
e.g. sliding gear 'out', top lever in position A and bottom lever all the way to the left, will give you 32 threads per inch if you're screwcutting using the half-nuts, or will advance the cut .007" per revolution if using the longitudinal power feed, .014" per revolution in cross feed i.e. facing.
That's probably as clear as mud; have a look at some threading videos on youtube (I highly recommend an obscure youtube channel called 'Tom's Techniques') that will demystify the threading process and put your gearbox arrangements into some context. Have a play with the levers, particularly the ones on the apron, and see what each one does.
Presumably there is also a moveable gear, probably at the back of the headstock, the 'sliding gear' that can either be 'in' or 'out'. The photo on the web page shows a lever on the headstock above the threading gearbox, I'll assume that is for the 'sliding gear'.
The chart on the gearbox is set out in columns which correspond to a position for the bottom selector lever directly below that column. The rows obviously refer to the position A, B or C of the lever on top of the gearbox.
The big numbers are threads-per-inch you will cut when using the half-nuts (on the apron) with the gearbox levers in each position. The small numbers are the distance the tool will move along the work when using the power feed,
e.g. sliding gear 'out', top lever in position A and bottom lever all the way to the left, will give you 32 threads per inch if you're screwcutting using the half-nuts, or will advance the cut .007" per revolution if using the longitudinal power feed, .014" per revolution in cross feed i.e. facing.
That's probably as clear as mud; have a look at some threading videos on youtube (I highly recommend an obscure youtube channel called 'Tom's Techniques') that will demystify the threading process and put your gearbox arrangements into some context. Have a play with the levers, particularly the ones on the apron, and see what each one does.
Lathe (n); a machine tool used in the production of milling machine components.
Milling Machine (n); a machine tool used in the production of lathe components.
Milling Machine (n); a machine tool used in the production of lathe components.