Making the index plates for drilling out lantern pinions on the milling head.

The first step was to cut brass discs from 2" bar.

These cut discs would be mounted in a pot chuck or stepped collet on my Sheldon lathe.

This is the collet to be used.


Here is one of the discs mounted in the collet - note the disc stands proud of the collet.


Using a large center drill to eliminate deflection, the center hole is started.


The hole is then drilled to 1/4" diameter.


The drilled disc is then faced off on both sides.


A cutter is next carefully ground on my Gorton single lip tool grinder...


... and mounted in the spindle of my Chronos wheel engine.


The discs are all notched with a 60 degree notch to convert them into index plates.


Another view of the process.


The notched discs are again faced off on the lathe and drilled to fit the milling head draw tube.





These 7 indexing plates will allow drilling lantern pinions having 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 18, and 20 pins.

I'll use the remaining three discs to make the missing 11, 17, and 19 index plates. But I need to switch the master plate on the Chronos wheel engine before making them.


Here is the milling head with an index plate mounted on a WW lathe.

And here it is mounted on the WW lathe set up for Pinion drilling and milling.




After drilling, the milling head casting was tapped.


This is the mounting for the indexing spring.


Here is the completed indexing spring.


This spring just clicks into "lock" position as the brass index wheel is rotated. It all works perfectly!

My next concern was for lighting. I located an LCD ring magnifying lamp with magnetic base and a very intense LCD bulb to use with a small desk lamp. These are shown below.

The results ...

Ring lamp only.


Both LCD lamps on the lathe ...

A view through the magnifying lens ...

In conclusion, I am pleased with the final result of this little project to make a lantern pinion drilling accessory. Based upon what I have seen with the Chinese milling attachment, the lathe would probably be an acceptable machine. I am so pleased with the outcome of this project that I have also ordered the pulley arm for supplying power to the milling head so that I can also use it under power and not merely as an index head for drilling/milling.

Click here to go to part one.