Don, I don't know for sure exactly what he was advocating. Hard to tell without a Ouija board...
He did, however, recommend not having a reversing switch on a lathe with a threaded spindle. That's his choice, but an awful lot of machinists wouldn't be caught dead without the reversing switch - threaded spindle or not. I'm one.
You are, of course, right about fractional vs. metric leadscrews and threading.
John Martin
According to John Martin :
[ ... ]
There is that. I guess that I was just assuming. :-)
As am I. (Well ... I do have three lathes without reversing switches -- but they are the small ones, the Unimat SL-1000, the Taig (though I am going to be switching in a small three-phase motor and VFD which will give it reversiblity), and the Emco-Maier Compact-5/CNC, which would have no problems with the chuck coming off under power, because the chucks mount to the flat nose of the spindle by three or four screws which pass through the body of the chuck. But I'm not sure how well the CNC could be adapted to reverse running of the DC motor. I've been more tempted to use some of the extra control outputs to switch between two speed control pots in place of the single one which is fitted as it comes from the factory.
Which is why I am very glad to have the Compact-5/CNC, since all it requires is rotating a switch to go between metric and imperial threads (and everything else). So -- so far - it is what I use when I need a metric thread, though I do have the transpose gears set for my
12x24" Clausing. So far, I have not had a project which needed metric threads large enough to require that machine.Enjoy, DoN.
Theres a 90Volt dayton on ebay right now with an OK buy it now price
3/4 HP. I've ignored it because i want more RPM that the title said.According to Rich Grise :
[ ... ]
This applies to gear headstock lathes, but not to belt drive ones, such as the Craftsman listed above, or my 12x24" Clausing, so it does not apply to the person who originated this thread.
Those are reversed by reversing the motor, which drives nothing but the spindle and (though the threading gears) the leadscrew and (if present) feed rod.
Enjoy, DoN.
3 years ago I got a 101-07402 made in 1938, but came with some mods; Timken tapered roller bearings and a modern 0.25 hp Century motor.
I wired it so it has reverse, but it is still anemic compared to my 3 hp Clausing.
Someone in bringing me a DC permanent magnet motor next month, that was surplussed form Precor and their treadmills. I am going to make my own controller.
I think the lathe can handle all kinds of torque, but the belt drive seems like it is always on the edge of oscillation.
Have something to add? Share your thoughts — no account required.
Ask the community — no account required