rhb
Aluminum
- Joined
- Apr 27, 2019
- Location
- A small town in central Arkansas
Due to some "cleverness" on my part I had to remove the spindle nuts on a new lathe I'm setting up. Prior to that the spindle bore clocked at less than a tenth TIR. I have no preload data from the OEM yet. I sent an email, but I expect it will take a few days to get a reply.
I've never worked in a big manufacturing plant, but I assume that the repair crew has rules of thumb for resetting preload when they don't have OEM data. Can anyone who has such experience comment?
I've read through the "Tips for adjusting spindle bearing preload on a lathe" thread. It generally describes what I have done, but I'm nervous. I'm OK with making mistakes, but not with doing damage.
What I did was clock the spindle bore and when I got to about a tenth TIR, stopped tightening the nut. I'm familiar with adjusting bearings based on both axial end play and friction and have the kit to do either. But I'm used to having a specification from the OEM.
Tearing it apart to find out who made the bearings and then track down the bearing OEM specs is not very attractive. That takes time and I want to get this in service.
The mechanical engineers who design machine tools have to determine required preload for whatever bearing system they decide to use. I've got a very large technical library, but I could find nothing on the topic other than in a Torrington catalog which did not list the size taper bearing bearing I'm dealing with. There was no discussion on how this is determined by the bearing OEM.
Ideally I'd like to find a mechanical engineer level discussion of how to determine the required preload for a bearing given a set of operating constraints for any type of bearing, taper, angular contact, deep groove, etc. It seems to me in my ignorance that a small number of people who have to do this daily know the answers.
Thanks,
Reg
I've never worked in a big manufacturing plant, but I assume that the repair crew has rules of thumb for resetting preload when they don't have OEM data. Can anyone who has such experience comment?
I've read through the "Tips for adjusting spindle bearing preload on a lathe" thread. It generally describes what I have done, but I'm nervous. I'm OK with making mistakes, but not with doing damage.
What I did was clock the spindle bore and when I got to about a tenth TIR, stopped tightening the nut. I'm familiar with adjusting bearings based on both axial end play and friction and have the kit to do either. But I'm used to having a specification from the OEM.
Tearing it apart to find out who made the bearings and then track down the bearing OEM specs is not very attractive. That takes time and I want to get this in service.
The mechanical engineers who design machine tools have to determine required preload for whatever bearing system they decide to use. I've got a very large technical library, but I could find nothing on the topic other than in a Torrington catalog which did not list the size taper bearing bearing I'm dealing with. There was no discussion on how this is determined by the bearing OEM.
Ideally I'd like to find a mechanical engineer level discussion of how to determine the required preload for a bearing given a set of operating constraints for any type of bearing, taper, angular contact, deep groove, etc. It seems to me in my ignorance that a small number of people who have to do this daily know the answers.
Thanks,
Reg