Atlas Craftsman 10" 12" Lathe 2 Step Motor Pulley 5/8 bore . Part Number 9-428.

[Bi11Hudson]

Bi11Hudson,

When you originally started this thread, you stated that you had a motor pulley 9-428 and that there wasn't enough material to bore out to 5/8". I have a 10-428 motor pulley on my 3996 with a 5/8" bore and as far as I knew, the only difference is the ID. And maybe the set screw is shorter.

Or maybe my assumption is incorrect and the only difference between 9-428 and 10-428 isn't just the ID or bore. The only drawing that we have of 10-428 is one drawn by a member of the groups.io Atlas-Craftsman group. How about posting a large side-view photo of 9-428?

I acquired the machine (101.27440) from someone who had acquired it used. There was no number cast into the pulley. When I changed the motor, I did measure the ID of the small pulley, it was less than .750. I felt that my skills were so poor that had I reamed it to .625, it would self destruct in short order. Making a proper two step pulley would have been the way to go, and I may still do that. But I doubt that I would spend the cash for a proper Atlas part. The use I make of the machine is not in production work and I seldom work steel. It is a very fancy hammer that I use for making "one-off" parts for my models.

By the way, I am not the originator of the post, just the first response with my "git by" attitude.

.

 

[wa5cab]

Bill,

OK.

 

[wa5cab]

anthonyc,

OK. Please confirm that the name plate with model and serial number are on the right end of the bed. Also,, whether or not 12L is also on the nameplate.

Back to the pulley and motor mounting, the design of the motor mounting bracket is such that although adjusting the motor will be relatively easy if you only loosen the mounting nuts enough to slide it around a little, moving it to different mounting holes will be tedious. What I think that I would do were it mine is to drill and tap a hole in the bottom of the 4" groove for the set screw. Cut off the 2" pulley groove and clean up the face of the cut. And cut the three inch groove down to 2" or better, 1.903". Then if to change between the small and large grooves requires, (remember that the 4" groove is a little small) loosen the four motor mounting nuts and slide the motor back a little bit. But you won't have to move the motor side ways.

 

[anthonyc]

Here is some information that may be helpful.
I do not see 12L on the unit.
The Part /Model number plate is on the back-side center of the bed.
The serial number is stamped at the end as shown
As for the pulley that was my thought as well.
I have attached photos of the motor and mounting bracket.