Help needed in reassembling headstock of a SB 9B

[JoeJoe62]

I am reassembling the headstock of a SB 9B lathe and was using an apparatus to press the spindle into place. It did not work. So I decided to see if the bull gear would fit on the spindle by hand outside the headstock. I found that the key barely fit into the keyway on the bull gear. I could not get the key all the way into the keyway. Now the bull gear is stuck on the spindle. I was following the instructions in the Guide to Renovating the South Bend Late step 107. I also saw several YouTube videos on how to remove/install the spindle into the headstock. In the videos, the bull gear appeared to easily slide on the spindle and the key fits in the keyway. My bull gear does not do so. I would appreciate recommendations on how to remove the stuck bull gear from the spindle. Thanks from a newbie.
Joe

 

[jim rozen]

Often the bore of the gear, and the exterior of the shaft are polished up before the press-up is done. Another trick is to be sure the key is chamfered on the ends to help it start cleanly into the keyway in the gear.

It sounds as though your assembly needs a gentle hydraulic press assist to get it apart again. If you don't have one then an automotive shop nearby can help. How far is the gear engaged on the spindle? Another issue is that the gear is cast iron and the spindle is steel. Cast iron has a larger thermal expansion coefficient than steel so gentle heat on the gear could get you out of the problem. Think hair dryer, or possibly the oven at 350 or so.

Wear gloves.

 

[JoeJoe62]

The heat gun worked. I have freed the bull gear from the spindle. Yeah!! Thanks for the recommendation. Do you suggest filing the key down a little?