How to finish a lathe gib holder

[Tom Kitta]

Here it is assembled in. But it does not tighten as I either have to add something to the "Green" area or I have to mill down a bit the area opposite to green.

So what should I do? Currently I think of adding a brass shim about 1mm thick to the green area.

What should I do? Other than this it fits perfectly. Original part was missing.

 

[Tom Kitta]

Come on, anyone?

 

[DavidR8]

If that's also the carriage lock then it seems to me that it should be loose till tightened?

 

[Tom Kitta]

If that's also the carriage lock then it seems to me that it should be loose till tightened?

Yes, that is correct. But when screw is tight it is not grabbing the underside. So I either have to shim to grab or mill the other side.

 

[YYCHM]

Shim.

 

[DavidR8]

Mill the other side would be my choice.

 

[YYCHM]

Mill the other side would be my choice.

Mill the other side of what? As in create a step in the lock plate? I'm not following.

 

[DavidR8]

Mill the other side of what? I'm not following.

Tom can either make the part that bears against the bottom of the ways thicker with a shim or mill away some of the area that bears against the bottom of the carriage so that it doesn't bottom out before it clamps down on the underside of the way.

 

[Tom O]

Can you slip a feeler gauge into it to see what the gap is?

 

[Susquatch]

Come on, anyone?

I didn't see your post till just now. Sorry about that. It looks like you are getting good input now though.

 

[Tom Kitta]

Can you slip a feeler gauge into it to see what the gap is?

Good idea!

Also I made the part from soft gray iron.

The difference is tiny, maybe a 1 thou. I cannot even place smallest feeler there.

 

[Tom O]

Maybe try some Prussian blue on it to make sure it’s sitting flat.

 

[PeterT]

I wasn't quite sure if your issue was the same as mine, disregard if not. My 14x40 had a very vague feeling saddle lock. Very little contact area & it was acting at a distance from the saddle underside. It would spin on its axle, loose orientation or stick the saddle movement depending on the gravity of the moon. Just plain goofy.

 

[PeterT]

I made this one. A profiled foot

 

[RobinHood]

On my three lathes, the carriage lock block looks something like this:

For best clamping force, one needs a pivot so the block can clamp onto the underside of the way. This is a very powerful set-up - I usually only “snug” the lock bolt.

 

[Susquatch]

My Lathe is similar to @RobinHood but sideways.

Looking at it from the tailstock it looks like this:

My drawing isn't great, the left side is quite a bit wider than as drawn. And the entire block extends along the way about 3 or 4 inches.

 

[Tom Kitta]

I wasn't quite sure if your issue was the same as mine, disregard if not. My 14x40 had a very vague feeling saddle lock. Very little contact area & it was acting at a distance from the saddle underside. It would spin on its axle, loose orientation or stick the saddle movement depending on the gravity of the moon. Just plain goofy.

My lathe is Czech made so they had enough foresight to add a pin - seen on picture that keeps things properly oriented.

There appears to be almost no difference height wise - maybe 0.001 between moving parts - this 0.001 could simply be wear.