11-30-2014, 01:11 PM
The motor on the Jet is a 1hp, 220V single phase unit. I believe them to be Optimistic Chinese Horsepower, which seem to be a bit different from US Horsepower. It was original to the machine. I don't think I've ever noticed any significant belt slippage with the link belt, I think it is just a less-than-awesome motor that I'm dealing with.
As an electrical guy by trade, I've set up many VFD's in the course of my work, I'm a huge fan of them. Yep, a VFD and a larger motor are sitting in the shop awaiting installation. The one slated to go on the Jet is a 2hp, 3 phase unit. I like over-sizing my VFD driven motors so that I can get the "original" HP even at much reduced speeds. The headstock of that machine is tapered roller bearing and I have run it at full speed for considerable time a few times (just to see what would happen) while monitoring the bearing temps. They barely got above ambient temp, so I'm pretty confident that they could easily run at higher speeds. If I'm feeling ambitious I may even get fancy and do tach feedback speed control, which is really cool, but can have it's own set of issues. I had that on one of the DC drives for a bandsaw I set up years ago and could get near full power at most any load over maybe a 40:1 speed range. Almost a servo drive.
I had just replaced the VFD in my Sheldon a while back when I started traveling for work. So while it runs, the VFD needs to be dialed in a bit more and the machine needs to be re-leveled and such as I had moved it to work on it. Also in line for that machine is a DRO install, have all the stuff, but you know...
Once I get that wrapped up, that will give me a lathe to use while I mess with the Jet motor/VFD. And I do like my Sheldon. It is a very nice machine.
And no need to be concerned about being critical, having been married for 30 years and six kids, I'm pretty thick skinned(!).
As an electrical guy by trade, I've set up many VFD's in the course of my work, I'm a huge fan of them. Yep, a VFD and a larger motor are sitting in the shop awaiting installation. The one slated to go on the Jet is a 2hp, 3 phase unit. I like over-sizing my VFD driven motors so that I can get the "original" HP even at much reduced speeds. The headstock of that machine is tapered roller bearing and I have run it at full speed for considerable time a few times (just to see what would happen) while monitoring the bearing temps. They barely got above ambient temp, so I'm pretty confident that they could easily run at higher speeds. If I'm feeling ambitious I may even get fancy and do tach feedback speed control, which is really cool, but can have it's own set of issues. I had that on one of the DC drives for a bandsaw I set up years ago and could get near full power at most any load over maybe a 40:1 speed range. Almost a servo drive.
I had just replaced the VFD in my Sheldon a while back when I started traveling for work. So while it runs, the VFD needs to be dialed in a bit more and the machine needs to be re-leveled and such as I had moved it to work on it. Also in line for that machine is a DRO install, have all the stuff, but you know...
Once I get that wrapped up, that will give me a lathe to use while I mess with the Jet motor/VFD. And I do like my Sheldon. It is a very nice machine.
And no need to be concerned about being critical, having been married for 30 years and six kids, I'm pretty thick skinned(!).