Removing The Spring Base In The Headstock Of The Grizzly Mill G0757

[Xiansheng]

Hi Everyone. I will be grateful for any advice about removing the spring base from the headstock of this milling machine. The spring base houses the return spring for the vertical spindle. It apparently is retained in the headstock by three small screws, described in the manual as setscrew M8-1.25 x 16. I have removed the cover spring and motion mechanism on the other side of the headstock.

As shown in the manual, there are three threaded holes eqi-sapced around the outside of the spring base close to the headstock casting. The spring base has some rotational and sideways play, but is held in place, apparently by screws in the three holes.

I have tried every instrument screwdriver and allen key that will fit in the hole, down to extremely small sizes, but none of them engage in whatever is in these holes. Every tool seems to bottom out at about 2 cm, so nothing is entering an Allen key hole in the end of a screw.

Has anyone removed the spring base on one of these machines? If so, can they let me in on the secret of how to remove it?

I should mention that the purpose of removing the base is to reposition the spindle lowering splined shaft in the rack on the spindle, to stop the handles clouting the table when the spindle is in the fully up position.

Regards John Poxon

 

[hman]

I don't have a G0757, but I'm willing to take a wild guess. I downloaded the manual and checked the diagram. Page 68 shows the headstock. I can't see where there are three equi-spaced fasteners, but it looks like there may be a set screw (#318, M8-1.25 x 16) coming in from underneath.

PS - Interference between the handles and the table or workpiece is a known issue with many mills, including the RF-30 clone that I have. I solved the problem by making new handle out of ~½" rod, turned down at one end to the root diameter of the threaded holes. Pressed some 8mm x 8mm magnets into an aluminum ring and pressed that onto the shaft. This make it easy to remove and/or reposition the handle into any one of the three (empty) holes. The magnets do a very good job of retaining the handle. Even releasing a fully lowered quill and letting it spin upward to stop does not dislodge the handle! Photos below.

 

[coffmajt]

Another solution is to make an adapter plate and mount a Bridgeport handle. I did that on my Grizzly mill and it works so much better

 

[brav65]

I don't have a G0757, but I'm willing to take a wild guess. I downloaded the manual and checked the diagram. Page 68 shows the headstock. I can't see where there are three equi-spaced fasteners, but it looks like there may be a set screw (#318, M8-1.25 x 16) coming in from underneath.

PS - Interference between the handles and the table or workpiece is a known issue with many mills, including the RF-30 clone that I have. I solved the problem by making new handle out of ~½" rod, turned down at one end to the root diameter of the threaded holes. Pressed some 8mm x 8mm magnets into an aluminum ring and pressed that onto the shaft. This make it easy to remove and/or reposition the handle into any one of the three (empty) holes. The magnets do a very good job of retaining the handle. Even releasing a fully lowered quill and letting it spin upward to stop does not dislodge the handle! Photos below.
View attachment 111100 View attachment 111101

Hey I have a handle made by the same guy! I recognize the golf balls!

 

[Xiansheng]

I don't have a G0757, but I'm willing to take a wild guess. I downloaded the manual and checked the diagram. Page 68 shows the headstock. I can't see where there are three equi-spaced fasteners, but it looks like there may be a set screw (#318, M8-1.25 x 16) coming in from underneath.

PS - Interference between the handles and the table or workpiece is a known issue with many mills, including the RF-30 clone that I have. I solved the problem by making new handle out of ~½" rod, turned down at one end to the root diameter of the threaded holes. Pressed some 8mm x 8mm magnets into an aluminum ring and pressed that onto the shaft. This make it easy to remove and/or reposition the handle into any one of the three (empty) holes. The magnets do a very good job of retaining the handle. Even releasing a fully lowered quill and letting it spin upward to stop does not dislodge the handle! Photos below.
View attachment 111100 View attachment 111101

Another solution is to make an adapter plate and mount a Bridgeport handle. I did that on my Grizzly mill and it works so much better

Hi Everyone.
I solved the mystery. As suggested above by Brave65, there is a set-screw under the head which locks the spring base in place and the three holes around the periphery of the spring base are not involved. The reason why I didn't see the set-screw is that it had been bogged and painted over by some clever Chinese. I felt the surface where it was buried and discovered a barely detectable indentation, which I tested and found I could could gouge bog from covering the screw. One undone, and another set-screw on the other side was similarly undone, the splined shaft could be removed and therefore can be re-positioned. Having gone this far I will attempt to remove the column from the headstock to clean around its top - I have noticed but been unable to remove some paint particles resting on top of the column. Now's my chance. Thanks for your help!
Regards Xiansheng