Headstock Indexing

VDH to Myford Super 7

Some years ago as a novice to clockmaking I decided to make the Geo H Thomas, Versatile Dividing Head. In many clockmaking books I saw the VDH used in many applications, however

I needed to index my lathe chuck and have a cutter mounted on the vertical slide.

I was thinking of starting to make the Bull Wheel indexing system when I thought, why dont I just mount my VDH direct to the spindle of the Myford, so I went out to the workshop and devised a way of mounting the VDH to the spindle.

Here is what I did.

The first thing was to make an adaptor from the ¾ ” spindle in the VDH to the lathe bore spindle 5/8”. It is a simple taper locking mechasism shown in fig 1,

I made shaft first, turning the OD and the female taper, also turned a smaller diameter in the center to enable expansion from the taper. I then turned the male taper on the same same cross slide setting to ensure a perfect fit. I slit the shaft with a 1/16” slitting saw to allow a taper pin to fit between the slots to stop the taper nut from turning, I have left it as driven home for clarity.

I then mounted the VDH to the exposed ¾ spindle to work out mounting points, once fitted ran under 0.001” true which I was very happy about.

I decided to mount a plate to the under side of the VDH to extend the mounting down to the fine feed/screw cutting, gear wheel, as my Myford has the gear box attached.

If your lathe is not equipped with a gear box, You will have to remove the stud carring the idler gear and the drive pin from the catch plate substituted. The brass block can be mounted on this, the quadrant will need to be loosened and dropped down slightly so the tumbler gears are dissengaged.

I mounted the aluminium plate to the under side of the VDH and observed the fitment would be straight forward.

I measured the space between the underside of the aluminium plate and fine feed/screw cutting shaft and obtained a measurment for the mounting block.

I assembled all the pieces with the VDH to determine the point of the two main parts came together. (See photo).

Its only a matter of rotating the brass clamp until the face is flush and sitting nicely against the underside of the aluminium plate, this will be 90 deg.

I wanted to drill and tap to be able to fastern the two pieces together, so in situe I cleaned both faces with acetone and bonded them together with “Weicon VM 120 Professional Grade Super Glue” for metal, this enabled me to remove the assembly, mount it in the mill and drill and tap without it moving from its desired position.

Continued from above….

I wanted to drill and tap to be able to fastern the two pieces together, so in situe I cleaned both faces with acetone and bonded them together with “Weicon VM 120 Professional Grade Super Glue” for metal, this enabled me to remove the assembly, mount it in the mill and drill and tap without it moving from its desired position.

It is now ready for a trial run, I insetred and tightened the socket head cap screw to clamp the shaft into the spindle, I slid the brass clamping block into place now holding the aluminium plate to mount VDH onto.

Slid the VDH into position and fasterned the four bolts, adjusted the angle of the faceplate for ease of use,then proceded to index my headstock.

It worked very well, I was very happy and now have no need to make the Headstock Dividing Attachment which uses the bull gear of the lathe.