This is an adaptor that I made for installing a lathe chuck with workpiece onto a rotary table. It also works to install the lathe chuck in a 5C indexer. The chucks are a 4 inch 3 jaw and a 6 inch 4 jaw that are used on a Myford Super 7 lathe. The first two pictures, below, are the front and rear of the adaptor. The threaded portion duplicates the lathe spindle. The shaft on the other side is turned to 3/4 inch diameter. the three brass set screws are to make sure that the chuck and the adaptor are fixed solidly together as unit and that the adaptor doesn't back off of the chuck. 
The next two pictures show the configurations of the backs of the two chucks, and the next two show the chucks with the adaptor installed and tightened.
Next are pictures of the bottom and top of the plate that the adaptor shaft goes through with three countersunk bolts to hold the adaptor and chuck.
The next pictures show the hold downs for the plate, and the chuck and adaptor secured to the plate, and the unit attached to the rotary table with the holddowns.
The final two pictures that I hope are attached show a screw jack that I made to remove the center that I made for the rotary table when using the adaptor. The normal center in the rotary is MT 3 or 4 (don't recall which). I obtained a MT adaptor for a smaller MT, and then bored it out for a snug fit with the 3/4 inch shaft. The jack screw has a hook on the end that catch through the slot in the MT insert, and allows it to be pull free and removed.Sorry if the pictures and text are somewhat disjointed. I haven't figured out how to insert the pictures in the text very well yet.
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The next two pictures show the configurations of the backs of the two chucks, and the next two show the chucks with the adaptor installed and tightened.
Next are pictures of the bottom and top of the plate that the adaptor shaft goes through with three countersunk bolts to hold the adaptor and chuck.
The next pictures show the hold downs for the plate, and the chuck and adaptor secured to the plate, and the unit attached to the rotary table with the holddowns.
The final two pictures that I hope are attached show a screw jack that I made to remove the center that I made for the rotary table when using the adaptor. The normal center in the rotary is MT 3 or 4 (don't recall which). I obtained a MT adaptor for a smaller MT, and then bored it out for a snug fit with the 3/4 inch shaft. The jack screw has a hook on the end that catch through the slot in the MT insert, and allows it to be pull free and removed.Sorry if the pictures and text are somewhat disjointed. I haven't figured out how to insert the pictures in the text very well yet.
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