Alignment Issues : Uni-Loc shaft on wood lathe

[8paulbreak]

Hello,
When mounting Uni-Loc shafts on the lathe, I use a spare pin in a key chuck and screw the shaft on, swapping centers at the tip depending on the task. The issue arises when fully tightening the shaft—it throws the alignment off by about an inch at the tip. If I center the tip manually, the shaft wobbles due to the angle.
The only workaround I’ve found is to back the shaft off about half a turn and tape the pin to prevent further tightening. The pin is straight, no thread damage, the centers are aligned, and this setup works fine with other pinned shafts—only Uni-Loc shafts are problematic, and are they all loose when you attached them but don't screw down? how snug are they suppose to be should and you be able to notice a gap?

Has anyone else run into this? Any tips for mounting Uni-Loc shafts on a wood lathe?

 

[DeeDeeCues]

Hello,
When mounting Uni-Loc shafts on the lathe, I use a spare pin in a key chuck and screw the shaft on, swapping centers at the tip depending on the task. The issue arises when fully tightening the shaft—it throws the alignment off by about an inch at the tip. If I center the tip manually, the shaft wobbles due to the angle.
The only workaround I’ve found is to back the shaft off about half a turn and tape the pin to prevent further tightening. The pin is straight, no thread damage, the centers are aligned, and this setup works fine with other pinned shafts—only Uni-Loc shafts are problematic, and are they all loose when you attached them but don't screw down? how snug are they suppose to be should and you be able to notice a gap?

Has anyone else run into this? Any tips for mounting Uni-Loc shafts on a wood lathe?

Get rid of the key chuck and get a Morse 2 to ER32 adapter. The key chuck is not a precision piece.

 

[Michael Webb]

Hello,
When mounting Uni-Loc shafts on the lathe, I use a spare pin in a key chuck and screw the shaft on, swapping centers at the tip depending on the task. The issue arises when fully tightening the shaft—it throws the alignment off by about an inch at the tip. If I center the tip manually, the shaft wobbles due to the angle.
The only workaround I’ve found is to back the shaft off about half a turn and tape the pin to prevent further tightening. The pin is straight, no thread damage, the centers are aligned, and this setup works fine with other pinned shafts—only Uni-Loc shafts are problematic, and are they all loose when you attached them but don't screw down? how snug are they suppose to be should and you be able to notice a gap?

Has anyone else run into this? Any tips for mounting Uni-Loc shafts on a wood lathe?

Seems like you have a mandrel issue if the shafts won't screw all the way down.

 

[DeeDeeCues]

Seems like you have a mandrel issue if the shafts won't screw all the way down.

What I'm reading is that he isn't using a mandrel, which might solve the issue. To me it sounds like he is using a Jacobs style chuck to hold a normal pin. The Jacobs may never be accurate enough for shaft work, their quality varies wildly (I know you know this, Mr Webb, it is for others).

 

[Michael Webb]

What I'm reading is that he isn't using a mandrel, which might solve the issue. To me it sounds like he is using a Jacobs style chuck to hold a normal pin. The Jacobs may never be accurate enough for shaft work, their quality varies wildly (I know you know this, Mr Webb, it is for others).

Amen
To try and spin uni loc without a mandrel is a horrible idea. Because of the way the inserts are made. You can't even spin them between centers, unless your center is thin eneogh to go past the threads and reach the inner barrel

 

[Dave38]

Yep....get a mandrel and the problem will disappear. On ANY joint....the pin does not make the alignment, it's the facing of the butt and shaft joints meeting together and being perfectly flat in relation to the center line of both pieces.