What makes a 'metric lathe' a Metric Lathe?

[Brent H]

One of the worst “metricfications” of the stupids that work in the measurements was the determination to remove fractions or ratios from the metric system. They destroyed the ratios for decimal equivalents and thus “screwed” (pun intended) the threading world.
The metric “ pitch “ to “threads per xx” would have been so easy to adapt. Ratios! Ya baby …. 10 threads per centimetre or the like - nope - idiots!

A “pure” metric lathe would have all gears made to MOD spec and metric trapezoid threads. All the ways etc would be to metric dimensions etc.

I have Miss Metric and she can put out metric work (threads, dials in metric etc) but she is grounded in imperial with standard gearing and imperial sizes. However, there are some down south relations with 1/2” diameter x 1.5mm pitch trapezoid threads ….

The best lathes can do a combination of both imperial and metric and some really cool ones like @RobinHood have dial gauges that can accurately switch from metric to imperial feed.

 

[jcdammeyer]

I left Holland at age 10 so no direct experience in NL. However the EU-based machinists I have seen do threading all seem to just leave the halfnut engaged. I personally tried using the threading dial a few times on imperial threads and found it unrewarding.
Now I just use the ELS

Flemish, mostly Dutch thankfully.

Well I enjoyed that. Thanks for the link.

I'm going to guess that his lathe is actually an imperial lathe. There was a threading dial but when you look closely there are two tangs on the cross slide and compound slide for two different scales. So he's got imperial and metric. His need to have a 127 tooth gear suggests if might be an imperial lead screw.

I think I'll watch a few more of those.

 

[Susquatch]

I think I'll watch a few more of those.

I couldn't get past the Phunkit Mit Frau part......

 

[Darren]

One of the worst “metricfications” of the stupids that work in the measurements was the determination to remove fractions or ratios from the metric system. They destroyed the ratios for decimal equivalents and thus “screwed” (pun intended) the threading world.
The metric “ pitch “ to “threads per xx” would have been so easy to adapt. Ratios! Ya baby …. 10 threads per centimetre or the like - nope - idiots!

A “pure” metric lathe would have all gears made to MOD spec and metric trapezoid threads. All the ways etc would be to metric dimensions etc.

I have Miss Metric and she can put out metric work (threads, dials in metric etc) but she is grounded in imperial with standard gearing and imperial sizes. However, there are some down south relations with 1/2” diameter x 1.5mm pitch trapezoid threads ….

The best lathes can do a combination of both imperial and metric and some really cool ones like @RobinHood have dial gauges that can accurately switch from metric to imperial feed.

My SM 1660 has metric and imperial dials and will cut every metric and imperial thread without changing the gearing. Its a fantastic machine, but I just wish it wasn't so heavy to operate. Even moving the TS is a two handed chore. Its nice to have a smaller lathe around. I've thought about adding an air bearing arrangement to the TS, but I doubt it will ever happen.