chipper bearings

[fixer upper guy]

Help! I'm trying to remove the bearings from my ancient promark 210 chipper. This is pre-Gravely, serial #000419. I'm not sure if the bearings are frozen on the shaft, or if these used a eccentric inner race? Does anyone have info on removing these?

 

[imagineero]

I have no specific information about your chipper, but removing bearings from shafts is a pretty run of the mill job if you're familiar with it. If you're not it might pay to get help from someone who is. In the shop we used to remove them by oxy generally. There's a technique to it, Usually cut the outer race off with a grinder, get the bearings out then use the oxy on the inner race. Due to the different temperature of the shaft and bearing you can usually cut the inner race off with no damage to the shaft. You have to be quick about it. One cut either side, and the race drops off. Clean the shaft up with some 80 grit emery tape and you're ready to fit new bearings. If you don't have an oxy, you can do it with a grinder but it takes a steady hand and a light touch. Finish up just shy of cutting through and then use a cold chisel and mallet to remove the race.

Shaun

 

[fixer upper guy]

promark 210

Thanks. I was going to use this method, but I wanted to get some input first. Does anyone out there have a good source for these bearings? They are installed in a cast bearing block. Looks like standard stuff. As to bearing removal, a friend mentioned eccentric inner races on some older machinery. Does anyone know if this is used on promark chippers?