grizzly gunsmith lathe tail stock won't lock tight.

[AllenH59]

Hi.. Looking for words of wisdom... A buddy bought a new lathe, and had it shipped up here to Canada, of course at great expense. The tail stock will not lock tight to the bed. it is a lever lock, and we have tried every position of the lever coming tight to lock it. Everything has been cleaned, including under the ways where the anchor block runs. (made up a part name, I am sure you know what I mean). The anchor block is very narrow for the ways, with only about .0625 grabbing on the bottom of the ways on one side. We are making an anchor block that fits, and I made a stud that is tighter in the threads in the cam block. Grizzly was called, and they have never heard of such a thing. Any advice appreciated.

[John Hasler]

Sounds like they shipped an anchor block intended for a different lathe.

[AllenH59]

The anchor block for the steady rest is the same.

[Harold_V]

Make a new one from thicker material, one that covers the entire area, yet still allows movement when released. It can be made of steel. You may discover that you must also make related pieces, to accommodate the change in thickness.

I suspect the one that has been supplied is allowing too much flexing--and may well be doing damage to the surface on which it makes contact (rounding the edge). Make the replacement as quickly as you can, so there is not continued damage (assuming there is some).

H

[AllenH59]

Harold, that is what we are doing, we are making one out of a piece of 1" plate, 6" long, that is a bit shorter than the bearing length of the tailstock. The anchor block it came with was 2-1/2" long. I highly doubt the 16 mm bolt that pulls up the anchor plate will bend the new anchor plate. I made the bolt out of a wheel stud for a big mining truck. Perhaps for some reason this lathe did come with the wrong parts. This is a popular model, and if this problem were common, someone here would have heard of it. My friend understands that it is not safe to use the tailstock if it is not locked in place.

[Harold_V]

Excellent!
That sounds like a winning combination.

H

[AllenH59]

Success... We built the parts as above, and with 130 ft lbs of torque on the cam it would lock, when set to lock at the top of the cam.

[SteveM]

One additional suggestion:

Put a spring between the tailstock underside and the block.

It will ensure that the block is not dragging on the underside of the ways once it is loosened.

Made a HUGE difference in how my tailstock releases.

Steve

[Russ Hanscom]

Strange, on my lever lock tail stock, there is a provision for adjusting the spacing, or free stud length. When mine got a trifle loose, adjusting the nut got the lever to lock in the correct position.

[AllenH59]

SteveM... There was a spring and a couple washers to ensure the anchor plate moved down when released on the original set up, we used them in the new setup and that is not a problem..
Russ: The only provision for adjusting the free stud length on this model is to shorten it up. This was done originally with a bolt, which was screwed up into the block that rides on the eccentric, in the repair I made a stud and we put a nut at the end of it. It was intended to be adjusted from below the anchor plate.

[Inspector]

This is what the G4003G manual says about torquing the tailstock.

"Optional: To precisely secure the tailstock, mount a 1⁄2" drive torque wrench in the square drive shown in Figure 34, then tighten the tailstock to 40 lbs/ft of torque. The center point will be drawn down as much as 0.006". Do not exceed the max torque or damage to ways and tailstock will occur"

I can see where a bigger part would spread the torque more but I think the 130 ft lbs/ft excessive. That's over 30 lbs/ft more than the lug nuts on my truck! If it was 130 lbs/in that would be something to crow about. I've never done much more than bump the leaver with my hand but I'll qualify that by saying I've never put anything heavy on it. If I ever do feel the need to put more force on it I'll do as you have and make a bigger part.

Pete

[Harold_V]

The numbers you quoted are in conflict.

H