101.21400 back gear

T

TechNova

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first time exposed to a lathe with back gear, have been using a SB 14. before. When I engage my back gear the spindle will not turn.
I bought it a few weeks ago and operates normally once I adjusted gibs and tightened change gears.
When I flip the eccentric lever up for the change gear the spindle will not spin by hand or motor.
The larger gear on the spindle, closer to the chuck has some play in it side to side, not sure if it could cause a bind.
I wiggled it and could not turn the spindle by hand.
What could cause this?
 
There is a pin that ties the large back gear to the pulleys; this must be retracted, then it should turn properly.
The pin is on the face of the back gear, next to the bearing face.
 
With a similar machine, 101.27440 12 X 36, I would advise that the pin addressed above unlocks the large gear. Pull it only far enough to release the gear, it can be removed if you pull it too far. To reengage takes a little finagling. While pressing (lightly) the lock pin, rotate the spindle by hand until it "finds" a locking hole. My gear is large, with several locking holes. That may vary from model to model.

A concern, if you have one, is a second pin toward the front at an "8 o'clock position" that is used with a series of holes for indexing. Mine has 60, that also may vary from model to model. The machine must never be powered on of course when the indexing is in use.

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Got the back gear working properly, pin was a little sticky, ran it in and out a few times. loosened up.
Thanks, I plan to buy a manual reprint soon.
 
Bi11Hudson said:
With a similar machine, 101.27440 12 X 36, I would advise that the pin addressed above unlocks the large gear. Pull it only far enough to release the gear, it can be removed if you pull it too far. To reengage takes a little finagling. While pressing (lightly) the lock pin, rotate the spindle by hand until it "finds" a locking hole. My gear is large, with several locking holes. That may vary from model to model.

A concern, if you have one, is a second pin toward the front at an "8 o'clock position" that is used with a series of holes for indexing. Mine has 60, that also may vary from model to model. The machine must never be powered on of course when the indexing is in use.

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Click to expand...
That second pin.... I saw last night a pin that had it's head tight against the back of the chuck. It has a pointed tip that engages one of the many holes in the larger spindle gear. It was obvious to me that it should not be engaged when running, but what would you use it for? Indexing? when and why? What instance would you use this to "lock" the spindle? surely not strong enough to use to lock spindle for chuck removal, looks pretty fragile.
 
Yes that other pin is a simple indexing device- not sure how useful it is
 
I found a parts book and manual on the vintage machinery site, helped me understand the indexing uses.
 
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