tailstock4
Cast Iron
- Joined
- Mar 3, 2013
- Location
- Oklahoma, USA
This is a 1968 10EE that was originally a modular machine. However, because of a bad motor, missing control module and other issues I decided to convert it to a VFD. The machine came out of a lab which was its only previous owner, so the mechanical condition was excellent. As an example, there was .0145” gap between tailstock flat and the underside of the flat on the saddle. So the ways were in good shape. Other than the drive, the only real surprise was it needed spindle bearings - something that I was originally unaware of. But because of the overall mechanical condition, I decided to completely disassemble, fix all the issues, clean, paint and reassemble. It took about 8 months.
I know there have been several conversions, but I did a couple of things different that might be of interest to some so I decided to post this.
The VFD I decided to use is a Nidec M701 and a Black Max 7.5 horse with gear reduction box and closed loop encoder feedback. It has a 20 olm, 1,500 watt brake. I retrained all of the original controls and functions. I purchased this all through DP Brown in Saginaw, MI. One of their head techs was of much help in programming in that he knew the drives well but also knew manual lathes. We were able to connect a laptop so that he could see the drive performance as it ran. His assistance in the tuning made a big difference in the performance of the drive.
The first thing I did differently was to change the air-cooling process. I closed off all openings to the underside and back side of the machine except two. The back bottom, lower right cover is for air intake and filtering. Air comes in through two Noctua fans, down through ducting, over the drive and a heat sink that I made for the drive. Air then goes back through a top opening of the motor bay and then travels over the motor through two more fans in a bulkhead I added. From there air blows over four resistors and out the last hole on the bottom of the base as exhaust. I did all this to ensure cooling. I also decided since I was closing it up that I would do some sound insulation. The result is a very quiet lathe.
The second thing I did was to address the alignment of the gearbox to the motor. I was unhappy with trying to simply relocate the original dowels as the shifting wasn’t as smooth as I though it should be. So I took apart the whole assembly (motor, adapter plate and gearbox) and assembled them vertically on a large angle plate. Then I took the whole assembly and put it on the radial drill. I fiddled around with it until the shifting was smooth. I then clamped the gear box and removed the pully side cover and drilled and reamed new dowel holes.
The results I think are pretty good. It is very quiet, smooth and powerful. It will drill a 1” hole in 1018 steel with a 3/16 pilot hole at 200 RPM in direct drive. There is no cogging even down to 1 or 2 RPB in direct drive. Braking performance with a forged steel set-true 6-jaw chuck is about 1 sec for 2,500 to 0, .5 sec for 1,500 to 0, and below 1,500 almost instant. When threading with the ELSR set at 400 RPM 13 TPI in direct drive, the carriage will stop exactly in the same place with no relief.
This leads to my question. I have thought about changing pulleys to make the drive 1-to-1. Pulley diameters now are 5 5/8 top, 6 7/16 bottom. I have the stock, and it could be done on my Pacemaker. Is this a worthwhile project? Any downside? I know it would lessen the back-gear range RPM-wise. What else?
I also included pictures of the 10EE sitting next to my Rivett 1020S. Interestingly, both machines had the spindle bearing changed. There are some differences and in my opinion the Rivett was the more difficult to change bearings in for couple of reasons.
Anyway, thanks to all those who helped in this project even if you didn’t know you were helping. I usually find a way to get things done when it comes to these machines, but it's always nice to find a road map if you can. Thanks.
I know there have been several conversions, but I did a couple of things different that might be of interest to some so I decided to post this.
The VFD I decided to use is a Nidec M701 and a Black Max 7.5 horse with gear reduction box and closed loop encoder feedback. It has a 20 olm, 1,500 watt brake. I retrained all of the original controls and functions. I purchased this all through DP Brown in Saginaw, MI. One of their head techs was of much help in programming in that he knew the drives well but also knew manual lathes. We were able to connect a laptop so that he could see the drive performance as it ran. His assistance in the tuning made a big difference in the performance of the drive.
The first thing I did differently was to change the air-cooling process. I closed off all openings to the underside and back side of the machine except two. The back bottom, lower right cover is for air intake and filtering. Air comes in through two Noctua fans, down through ducting, over the drive and a heat sink that I made for the drive. Air then goes back through a top opening of the motor bay and then travels over the motor through two more fans in a bulkhead I added. From there air blows over four resistors and out the last hole on the bottom of the base as exhaust. I did all this to ensure cooling. I also decided since I was closing it up that I would do some sound insulation. The result is a very quiet lathe.
The second thing I did was to address the alignment of the gearbox to the motor. I was unhappy with trying to simply relocate the original dowels as the shifting wasn’t as smooth as I though it should be. So I took apart the whole assembly (motor, adapter plate and gearbox) and assembled them vertically on a large angle plate. Then I took the whole assembly and put it on the radial drill. I fiddled around with it until the shifting was smooth. I then clamped the gear box and removed the pully side cover and drilled and reamed new dowel holes.
The results I think are pretty good. It is very quiet, smooth and powerful. It will drill a 1” hole in 1018 steel with a 3/16 pilot hole at 200 RPM in direct drive. There is no cogging even down to 1 or 2 RPB in direct drive. Braking performance with a forged steel set-true 6-jaw chuck is about 1 sec for 2,500 to 0, .5 sec for 1,500 to 0, and below 1,500 almost instant. When threading with the ELSR set at 400 RPM 13 TPI in direct drive, the carriage will stop exactly in the same place with no relief.
This leads to my question. I have thought about changing pulleys to make the drive 1-to-1. Pulley diameters now are 5 5/8 top, 6 7/16 bottom. I have the stock, and it could be done on my Pacemaker. Is this a worthwhile project? Any downside? I know it would lessen the back-gear range RPM-wise. What else?
I also included pictures of the 10EE sitting next to my Rivett 1020S. Interestingly, both machines had the spindle bearing changed. There are some differences and in my opinion the Rivett was the more difficult to change bearings in for couple of reasons.
Anyway, thanks to all those who helped in this project even if you didn’t know you were helping. I usually find a way to get things done when it comes to these machines, but it's always nice to find a road map if you can. Thanks.