How can this physically work?

[Mark Gibney]

This post is a follow up to my recent question asking for help on getting the outfeed table on a used SCMI F410 to move.
I managed to free up the table, I guess it was "frozen" in place perhaps by the lubricants gelling. It weighs a ton, and I used an engine hoist to lift it back up.

My question now is how on earth can the threaded rod that raises / lowers this table actually work?
Right now it doesn't work, I cannot move the table using this knob and rod.

The rod threads into a rectangular collar on an axel that pushes the cams and thus moves the table.
But, at the end where the hand knob is, the rod simply comes through the body of the jointer, through a nickle plated cover and then ends in a knob.
So when the knob is turned, the rod does not push against anything, it is not captured, and so physically how can it apply any pressure against the cam axel?
It doesn't make any sense to me, yet it seems to be this way when I look at the exploded schematic.

IMG_6403.jpg Screen Shot 2020-08-14 at 7.16.26 AM.png

To my mind there would need to be a nut in the bump of that cover plate for the threads on the rod to push against, but there is nothing there, and it seems that this is by design.

If anyone has any insights or knowledge about this I'd really appreciate you sharing.

thanks, Mark

[J.R. Rutter]

Does the rod use the threads where it attaches to the lever #21 to pivot the axle?

[glenn bradley]

Agree. The push and pull of the threads provide the lever. The lower rod is the pivot axis.

[Wes Grass]

Looks like it has a thrust bearing of some sort in the bracket (13), that the collar (12) pushes against to elevate the table. And 17 is a lock for it?

So when you turn the knob CCW it backs out of the bracket?

[Mark Gibney]

Wes, parts 12 and 17 are just a lock, they are not involved in any of the mechanics. The collar 12 is just loose on the rod until 17 is tightened up on it.

JR yes, somehow the rod pushes the collar to pivot the axel, but as this rod is not constrained down at the other end where the knob is I can't work out how it does this, and so I can't address the issue. It's a parts machine! well, not yet...

[Wes Grass]

Yeah, my first guess was a shaft lock, but I was looking for something of a thrust collar to make it work.

14 looks like a retaining ring, maybe so the rod can pull the table down. Is there any shoulder on the shaft that could trap a bearing between it and the (maybe) retaining ring?

No evidence that a bearing inside the flange is now missing?

[Wes Grass]

Cant edit, only delete from my phone.

The flange looks to have an angled pocket formed in it, to align a thrust bearing square to the shaft. It's also heavy gauge material, retained by high strength screws.

*HAS* to be something for the screw to bear on. IMO, of course. I'm not the one staring directly at it.