More 12x36 questions

[mecompco]

Spent some time messing with the lathe today. For some reason, it doesn't seem to run smoothly--kind of like it is going out of gear. It runs good for a few seconds, then starts to "hitch". Everything seems tight, but I'm not totally confident that the motor is mounted perfect.

I notice that the big lever you pull (not sure what it's called) to get it out of gear does not lock down, it slips up out of the catch no matter how I adjust it.



Next, the motor does not seem to pivot down enough to tension the belt on the small drive pulley (large one seems fine) the picture is with the motor all the way down.



Last thing--there doesn't seem to be a whole lot of clearance between the motor mount and the spindle. Motor is all the way down in the picture.



Thanks for any thoughts!

Regards,
Michael

 

[wa5cab]

Michael,

I'm not sure what the answers to your other questions are, except to say that if the machine runs smoothly and then stops running smoothly, something must be moving and if you watch it change enough times, you should spot it.

But the reason that the belt is slack in the outer pulley grooves is that you have a dual belt motor pulley, not a 2-step. The OD of the outer groove on the motor pulley should be 4.390 or thereabouts. And the inner one should be 1.930".

Robert D.

 

[mecompco]

Michael,

I'm not sure what the answers to your other questions are, except to say that if the machine runs smoothly and then stops running smoothly, something must be moving and if you watch it change enough times, you should spot it.

But the reason that the belt is slack in the outer pulley grooves is that you have a dual belt motor pulley, not a 2-step. The OD of the outer groove on the motor pulley should be 4.390 or thereabouts. And the inner one should be 1.930".

Robert D.

Robert, that explains it! So to use the faster speeds, I need a new motor pulley with the correct dimensions. I will see about finding one (suggestions on where to procure one are welcome).

I'm hoping I can get the PO of the machine over to help me figure out the vibration problems. Will post when a solution is found.

Regards,
Michael

 

[wa5cab]

Yes. The pulley is a 10-428. There is a drawing for making one out of solid aluminum in Downloads. Also, Clausing may have one, although it will certainly cost more than something from Harbor Freight. In the meantime, You could check the cheap places for single step pulleys of approximately the right diameters.

Robert D.

 

[MikeMc]

I don't know what that big lever you pull is called either but the way it was adjusted when I got my lathe caused me to think it was only used to slack the belts for speed changes and not engaged when turning. Of course I've never read the manual so I may be full of it, actually Brother will swear to the fact.
HTH,
MikeMc
PS: Having turned from 1/4" steel to 9 1/2" AL, I've not used the higher speeds but may when turning wood.
MM

 

[ELHEAD]

I believe the lever referred to is the " belt tension lever". Check downloads for Craftsman Owners Manual 101.28990

 

[wa5cab]

101.28990 is the final 12x36 under drive model. From just the photos shown, you need the manual on either 101.07403 (change gears) or 101.27440 (QCGB), both of which are in Downloads.