Hood
I am obsessed.
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This is for @ronan who was asking about the conversion I did to my Triumph 2000 lathe. The headstock was, as is common on the newer Colchester's, extremely noisy due to the gears being worn.
It was that noisy that I had to wear ear defenders and even then I was getting a headache after using for a while. My solution is not perfect as the servo is not really big enough due to the KW dropping as I lower the RPM because I am not using gearing to drop the revs as the original motor would, torque is almost constant from Zero-full rpm but that doesn't really help when you are also needing the power.
Anyway I made up a large plate to fit the motor behind the headstock and had the belt from it connect direct to the spindle, that way the gears for the feeds were still in play but the gearing from the original motor to the spindle are now out of the equation as I have the speed handles turned so that they are basically in neutral.
I fitted a couple of limit switches so that I could still use the lever for Fwd, Off, Rev. I have the servo drive configured to be at zero speed when it sees one of these limits, when it no longer sees that limit it will change over to 0-10v command mode and I can adjust the rpm via a potentiometer which I have on a panel on the headstock. When I put the lever to reverse it operates another limit switch and that works a relay which inverts the 0-10v signal and the spindle will then go in the reverse direction.
On the panel that the pot is on I also have an enable switch and a reset switch for the servo drive. I also have a meter and I used a scaled output from the servo drive so that the RPM is indicated.
The servo motor was 4000rpm max so I geared 2:1 so that I can still get 2000rpm out of the lathe however I would be better gearing 4:1 as that would give me double the KW I have available at any given RPM compared to what it is now. Obviously the Max RPM I could achieve would be 1000rpm but I am very rarely over that anyway so it would be a worthwhile sacrifice, maybe one day I will get round to it
Anyway some pics.
It was that noisy that I had to wear ear defenders and even then I was getting a headache after using for a while. My solution is not perfect as the servo is not really big enough due to the KW dropping as I lower the RPM because I am not using gearing to drop the revs as the original motor would, torque is almost constant from Zero-full rpm but that doesn't really help when you are also needing the power.
Anyway I made up a large plate to fit the motor behind the headstock and had the belt from it connect direct to the spindle, that way the gears for the feeds were still in play but the gearing from the original motor to the spindle are now out of the equation as I have the speed handles turned so that they are basically in neutral.
I fitted a couple of limit switches so that I could still use the lever for Fwd, Off, Rev. I have the servo drive configured to be at zero speed when it sees one of these limits, when it no longer sees that limit it will change over to 0-10v command mode and I can adjust the rpm via a potentiometer which I have on a panel on the headstock. When I put the lever to reverse it operates another limit switch and that works a relay which inverts the 0-10v signal and the spindle will then go in the reverse direction.
On the panel that the pot is on I also have an enable switch and a reset switch for the servo drive. I also have a meter and I used a scaled output from the servo drive so that the RPM is indicated.
The servo motor was 4000rpm max so I geared 2:1 so that I can still get 2000rpm out of the lathe however I would be better gearing 4:1 as that would give me double the KW I have available at any given RPM compared to what it is now. Obviously the Max RPM I could achieve would be 1000rpm but I am very rarely over that anyway so it would be a worthwhile sacrifice, maybe one day I will get round to it
Anyway some pics.