I have the need to cut metric threads on my older inch engine lathes on a regular basis. I know that compound gearing is the way it's done. I've looked at what it will take to setup one or both of my lathes. The time, the expense and then the cost of the time to constantly change back and forth seems like it would be smarter to just sell the lathes I have and buy machines that cut inch and metric.
Both my lathes have a lever to quickly de-couple the feedboxes from the spindle. Both have room for a fair size 3KWish servo to mount inside the geartrain cover. A friend/biz partner already has a generic touchscreen GUI that he uses for industrial process control that could work for an electronic leadscrew controller.
I'm really thinking about doing it. I don't want to CNC my manual lathes. I have CNC lathes. What I want is just to cut metric pitches with an inch lathe. And without a bunch of BS. Like same amount of time to setup to cut metric threads as it takes to setup the feedbox for inch threads now.
I'm thinking a prox switch on the feed box disconnect lever that disables the servo whenever the gearbox is physically connected to the spindle. The unpowered servo can just spin all the time, but can only be powered when the feedbox is not physically geared to the spindle.
Without adding a bunch of fluff, can anyone think of features that could be incorporated to make metric threading gooder? Like a "rewind" or return to start feature so there would be no need to reverse the spindle?
Is there any way it could be setup so the half nut could be used? Kind of like the "rewind" idea, but instead you setup a carriage stop and engage the half nut at the same bed location into a stopped leadscrew?
Both my lathes have a lever to quickly de-couple the feedboxes from the spindle. Both have room for a fair size 3KWish servo to mount inside the geartrain cover. A friend/biz partner already has a generic touchscreen GUI that he uses for industrial process control that could work for an electronic leadscrew controller.
I'm really thinking about doing it. I don't want to CNC my manual lathes. I have CNC lathes. What I want is just to cut metric pitches with an inch lathe. And without a bunch of BS. Like same amount of time to setup to cut metric threads as it takes to setup the feedbox for inch threads now.
I'm thinking a prox switch on the feed box disconnect lever that disables the servo whenever the gearbox is physically connected to the spindle. The unpowered servo can just spin all the time, but can only be powered when the feedbox is not physically geared to the spindle.
Without adding a bunch of fluff, can anyone think of features that could be incorporated to make metric threading gooder? Like a "rewind" or return to start feature so there would be no need to reverse the spindle?
Is there any way it could be setup so the half nut could be used? Kind of like the "rewind" idea, but instead you setup a carriage stop and engage the half nut at the same bed location into a stopped leadscrew?