It's all metric.is it metric/imperial or just metric.
met/imperial have imperial screws, converting to metric via 127 hand wheels. A metric will be all metric. Not easy to cut none-metric threads on metric only machine
is it metric/imperial or just metric.
met/imperial have imperial screws, converting to metric via 127 hand wheels. A metric will be all metric. Not easy to cut none-metric threads on metric only machine
How come? Is that something specific to an M300? I cut imperial threads quite regularly (albeit grudgingly) on my metric only machine. I see it as no more difficult than cutting metric threads on an imperial machine. You've got to keep the half-nuts engaged rather than using the thread dial indicator, but that's true cutting metric on an imperial machine too.
The conversion factor is 25.4....or 254 the prime factor is 127...which is why a 127T gearwheel is employed. Errors will occur if a 63T wheel is used.
You can do it either way round but it's a little more straightforward cutting metric with an imperial screw.
Out of curiosity, what makes it more straightforward? To cut imperial threads on my lathe (a metric one), I look at the thread cutting chart on the side, fit the change gears that are listed (the standard ones will do all metric threads but not imperial), choose the gearbox setting that's listed, then cut the thread keeping the half-nuts engaged. What's different with an imperial leadscrew cutting metric?
Out of curiosity, what makes it more straightforward?
Strangely the gears seem to be MOD 1.75 (not exactly common!) and then change to something neither imperial nor metric.
The M300 has been keeping me busy. I stripped the apron and assessed wear - mostly moderate and confined to the saddle handwheel gear train. I investigated buying off the shelf gears and machining down since most of these are just pinned to shafts. Strangely the gears seem to be MOD 1.75 (not exactly common!) and then change to something neither imperial nor metric. The handwheel shaft is slightly worn where it passes through the apron - I'll take measurements since that should be relatively straightforward to remanufacture.