Here are some photos of a Chandler Duplex Boring Head. I have used boring heads before, but do not understand the way this one works. Is it supposed to generate on its own, or does it work like any other boring head? I guess what I do not understand is the purpose of the dial at the top near the mounting threads. Speaking of threads, this one is a 3" with approx. 6 tpi. Anyone ever heard of this size? I imagine it is made to adapt to one of these tool holders I have listed in another post.
Any info is appreciated.....thanks..gary

another

I am not familiar with this unit, but if it is a boring and facing head, then the adjustment ring could be the feedrate per revolution. The thing may ratchet several times per revolution to accomplish the feed movement on the slide.

A reaction bar is also required for the feed mechanism to work against. There should be a hole in a slip collar somewhere on the thing to insert a rod. This rod will be held stationary while the spindle rotates the head, and the feed mechanism will then begin to work.

I hope posting all of these pics doesn't eat up to much of your server space, but I do have accessories. Please feel free to delete pics when I get too many on here, I have cropped and reduced the file size to help out. Here is all the stuff that goes with the head.

another

The thread at the mount end will fit a P & W jig borer spindle. Remove the collet nut then the boring head will fit right in. Very solid. I was looking for information on lubrication for a Chandler Mod J 84 that i won on eBay.