Back gear pin

[psychodelicdan]

Hi all
My Atlas 101.127440 12/36 has a issue. The back gear pin on the bull gear will not stay in at higher rpms. It likes to slip out and of course everything stops. I don't have a Manual and can see or feel nothing that would "lock" the pin in place.
Any ideas? Thanks
Dan


Master of unfinished projects

 

[wa5cab]

Dan,

In the bull gear is (should be) a 9-61 Spring and a 10-256 ball-nose pin. Possibly the pin is stuck in the hole. I've never had the parts out of my machine so couldn't tell you how to get at them.

Robert D.

 

[psychodelicdan]

I believe I understand what you are describing and I bet it's tough to get to.
Dan


Master of unfinished projects

 

[pdentrem]

This may not apply as my Atlas was older.
The bull gear pin can be rotated 180 degrees to unlock the ball nosed pin. To remove the bull pin now pull it out towards the tailstock while put a finger on the inside of the casting if you can to stop the little detent pin and spring from going flying around the headstock. It might be the spring has collapsed, the little detent holes on the bull pin are too worn to hold properly. As well it could be the bull gear itself, the hole that the pin goes into has too much taper, worn as bit and it is cams the bull lock pin out under load.
To reinstall, once you have the spring and the ball nosed pin in place you have to depress them to allow the bull lock pin to slide over top of them. You can use a piece of stiff shim stock or the like. Once they are back together, make sure the bull pin is oriented to way that the detents are facing the little ball nosed pin.
Hope this helps
Pierre

 

[psychodelicdan]

Thank you very much Pierre. Next time out in the shop Ill check that out.
Dan


Master of unfinished projects