10f-45 Bushing Removal (crossfeed Screw Bushings, Craftsman 101.07403)

[ZZYL-Vulcan]

Hey guys, I ordered a new crossfeed screw bearing, and realized I ordered the wrong one. Return is an option, but upon inspection, the only difference that will affect my performance is the bushings on the new bearing. The inside diameter on the new bushings are about .005 larger than the one I am replacing. I measured the outside diameter of both sets of bushings and they appear to be the same. Is it possible to remove them and swap them? How would I do so? Other relevant info, the new bearing is from a 10" (TV48), and has more threads than the 10F-46 I am replacing. I like the new bearing, and it screws right in to place. Overall length of the bearing is the same. Thanks for any help!

-Vulcan-

 

[Rob]

Atlas sold the bushings separate so you should be able to replace them. I believe you have the same part just maybe manufacturing differance between years. Was this new item used or new? Pics please.

 

[ZZYL-Vulcan]

Hey thanks Rob, the part is almost the same, but there are some differences. The only major noticeable difference upon inspection is the threads on the "new" bearing are longer. The bearing screws right into the carriage. The measurable difference is the one I mentioned, the inside diameter of the bushings. I installed the new one and am going to try it out, but I do still want to figure out how to replace the bushings. The bearing itself is certainly easy enough to remove...

The "new" bearing is used, although in better shape than the original bearing. I had considered that the inside diameter difference might be from wear. I'm not sure. Either way I would like to change them. There is a noticeable (although slight) difference in play in the fit of the crossfeed screw inside the bushing. I am unsure if this will affect the accuracy of the machine. If so id imagine it would be slight, but realistically, which machinist wants to accept slight inaccuracies in their work?

Also the index line on the bearing does not sit in the correct position after installation (it faces "down," 180 degrees opposite the correct position). I have remedied this by scribing a new line in the correct location.

As far as pics go, I might snap a few this afternoon, but honestly its not worth the effort. The difference I am concerned with would not be perceptible via camera, so don't be offended if I don't post any.

And to anyone else reading this, I would love to know how to remove those bushings!

 

[wa5cab]

Vulcan,

I've never changed the bushings in my bearing but have always assumed that the hole through the bearing is the same diameter all the way through (not counterbored at each end). Assuming that is the case, the way to remove the old bushings is to press one all the way through, pushing the other one out when the first one gets to it. To do this, take a piece of round stock (steel) that will be a slip fit through the hole in the bearing. Cut is about 1/2" to 3/4" longer than the bearing. On one end, turn down to 3/8" by 1/4" long for a pilot, and slightly bevel the shoulder. Using this and a press, push both bushings out one end. You will also need a receiver piece with a hole in it that is a slip fit for the bushings. Before inserting the pusher rod in the top bushing, feed it up through the hole in the receiver and use it to align the bottom bushing with the receiver hole.

On the alignment of the Witness Mark, I always assumed that this was cut during assembly as although a standard reference block could have been made to get the mark always in the proper position WRT the threads on the bearing, for this to work they would also have to tightly control the thread start in the hole in the saddle. And that isn't a trivial exercise..

 

[ZZYL-Vulcan]

Hey thanks Rob. That ought to do it. I hadn't thought of pushing both through in the same direction, but that is the only reasonable proposition. I will give it a shot, when I am ready. I wont be ready to do this until I get the rest of the lathe back together, but I'm nearing completion. I still have to finish the headstock, but the carriage, bed and tailstock are finished...

 

[wa5cab]

OK. If you were once in the starter and generator rebuilding business, you might have a bushing puller that would pull both of them from the near ends. But they were pretty pricey back in the day.