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Where are the knee locks on a Millrite MVI vertical mill?

I recently got a Millrite MVI vertical mill, and am learning how to use it. I have found all the locks but the knee lock. The closest I have found is two long hex socket cap screws that bear down on the knee gib, in the company of what appear to be the gib adjustments (long hex socket setscrews with locknuts). I would have expected something with a handle, for easy tightening and loosening.

The long hex socket cap screws don't seem to have quite enough thread to be correct, and don't bear squarely upon the back of the gib (which is parallel to the dovetail); two more reasons to think that the original gib locks have been lost.

Does anyone have a manual page that shows exactly how this is supposed to work? Or a photo or two? Or an exploded parts diagram? One assumes that there is for one a missing piece that has a slanted dog point, perhaps made of brass, to bear correctly upon the back of the gib. Or a 5/16-inch brass ball loose in the hole. I'm afraid to clamp the gib hard using the current setup, for fear of cracking the gib in half, from the point load imposed by the corner of the hardened socket cap screw. Although from the tips of the two cap screws, it seems that people have been doing just that. The clamp isn't that firm though.

I'd like to have some idea what was supposed to go there, and what to worry about, before I invent an answer.

Thanks,

Joe Gwinn

Reply to
Joseph Gwinn
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Gunner

"Deep in her heart, every moslem woman yearns to show us her t*ts" John Griffin

Reply to
Gunner

Thanks, but I do have that manual, and it mentions two "5/8 head locking screws" that one tightens with the big crank handle used to raise and lower the knee. These two locking screws are lost, being replaced by those two large (3/8-16) hex socket cap screws that don't quite fit. It's this that I'm trying to bring back to correct function.

The fact that they use the big crank handle implies that it takes some force to lock the knee.

This afternoon was spent taking apart and cleaning the quill raise/lower crank mechanism. All the stiffness was due to old grease gumming things up. There was no wear on the big bronze nut and large steel acme leadscrew. Nor were the thrust roller bearings worn at all. Just gummed up. Soak in solvent, clean, grease the acme thread and nut, oil the rest with way oil. It now turns very easily and smoothly. Backlash is still about 0.010", but I bet it was that way from the start.

Joe Gwinn

Reply to
Joseph Gwinn

To me, anyway, it implies nothing of the sort. The crank handle is used to raise and lower the knee. That means it's right there when you need to lock the knee. It's used because it's handy. Yes, they could supply you with a second, smaller, wrench just for the knee locks. Then you'd have one more wrench to lose.

John Martin

Reply to
John Martin

Indeed

Gunner

Political Correctness

A doctrine fostered by a delusional, illogical liberal minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.

Reply to
Gunner

I agree, although you can probably develop quite a bit of torque with that big handle. Therefore they probably made sure that those kind of forces wouldn't put undue wear or strain on the mechanism.

Reply to
woodworker88

Well, it must tolerate lots of force, because with ordinary use and a big crank, it's going to get lots of force.

Joe Gwinn

Reply to
Joseph Gwinn

They make spark plug sockets in 1/2" square drive, and my 1/2" square drive torque wrench goes to 150 foot pounds. So, I guess I'm supposed to really sock those plugs down tight, right? Or they wouldn't make spark plug sockets in any larger than 1/4" drive....

How about oil pan drain plugs? 7/8" hex, takes a long wrench. Man, you can really torque those down, can't you?

The trap connections under your bathroom take a pretty good sized pipe wrench to tighten, so they must be made to be really cranked down.

The manufacturers, Joe, expect machinists to possess and to exercise a little bit of common sense when using their products.

John Martin

Reply to
John Martin

Yeah, yeah, yeah ...

But don't put a burly crank with a 12" throw if you expect inch-ounces of torque. Doing so is asking for it, and customers will not be amused. So, most likely, the correct range is not inch-ounces.

Joe Gwinn

Reply to
Joseph Gwinn

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