Monday, Sep 12 2016
The cheap MT2 center I ordered arrived so I used it to get a rough check of the headstock to tailstock alignment.
Top view: roughly centered
Side view: closer
Side view: not so close
The difference between the 2nd and 3rd picture above is that the spindle has been rotated 180˚. As measured yesterday the spindle has about an 0.008” run-out. With this cheap center I’m measuring close to .020” runout at the tip. That’s with the new sleeve bearings. I’m not sure what I’m going to do about that, if anything. It is a 65+ year old lathe.
Friday, Sep 30 2016
I haven’t documented the many times I’ve been out in the garage playing with the lathe. I turned down the cheap center until it ran mostly true (less than .0015”). To bad that once removed that measurement is meaningless unless I happen to re-install it exactly as it came out. However, it did show that my headstock and tailstock are mostly aligned on the vertical axis.
I also faced the backing plate for the 3 jaw chuck (again). When trying to make the collars for the back gears everything got out of whack. Not sure what happened. Perhaps the spindle loosened up some with use. I tightened the spindle adjusting collar and faced the backing plate a third time. That seemed to be better – run out at the edge of the plate was between .001" and .002". Good, except it doesn’t seem to stay that way.
Of course I’d already faced, center drilled, drilled, and partially bored the holes for the back gear collars I was attempting to make. Turning them to size after playing with the chuck made the outside diameter excentric to the inside diameter. Good thing it doesn’t matter for this application. I also got the ID a bit too big and the OD a bit too small and the turned finish is terrible.
Back gears installed
Left collar
right collar
When the next owner of this lathe pulls the back gear assembly apart he’ll no doubt wonder what kind of incompetent idiot machined them. Well, they work. And they are only the second thing I’ve machined in the last 46 years. The first thing was the chuck backing plate. Yeah, I know that one of the set screws is a bit too long. It was the last 8-32 set screw I had on hand.
Now I can think about a replacment ball crank for the cross slide. And a holder to mount my test indicator to the tool post.