Thread dial disengaging

[SE18]

Hi all, It's been a long time since I had to make screws on my SB9A so I disengaged the thread dial from the acme thread. Now I need a screw so I re-engaged it.

The problem I'm having is that the thread dial gear engages and then suddenly disengages on its own. I know I'm seating it correctly in the acme thread which drives it but it mysteriously will pop back out in as little as one pass.

Any suggestions appreciated!

 

[4ssss]

Start your lathe and hold the thread dial against the lead screw and see what happens. There is a pin that holds that lower gear on a shaft that runs to the top of the dial and it may be disengaged.

 

[SE18]

Thanks, I'll give it a try.

 

[benmychree]

Did you tighten the bolt that holds the dial assembly against/away from the lead screw?

 

[mikey]

Hope its something simple, like not securely locking down the screw that holds the indicator in place. A bent leadscrew will kick out the indicator, too.

 

[SE18]

Didn't work. I did tighten the square bolt (1/4").

 

[SE18]

How would a leadscrew bend? It worked previously and I didn't do anything to bend it that I know of?

 

[benmychree]

Does the dial turn freely when it is disengaged?

 

[SE18]

let me back up for a moment. I did move the lathe with a strap and it was some time ago so it could be that the leadscrew is bent. Thanks for your insights!

 

[SE18]

yes, and I cleaned it