Pics would be very helpful in determining what you are referring too! Since I am not sure if we are talking about the same thing or not here are some pics of how my KMG clone works. Maybe you will be able to determine from them how to do what you are talking about.
The tube on the right is for the tooling arm, the attachments can be changed out by loosening and sliding the 1/2" bolt out of the arm itself. The 3/8" cap bolt holds tension on the 1/2" bolt. The tube on the left is the one for the work rest. The last pic shows the work rest in place.
Some will use multiple tooling arms to eliminate the need to loosen the cap bolt and change the head, IE 10" wheel or platen. I take an extra couple of minutes and loosen the 3/8" cap bolt and change the attachment that way!
This is a view looking down on the machine.The actual tension for both the tooling arm and the work rest arm are achived by this item, a 3/8" ratchet lever knob.
Grinder with work rest in place.
I have changed the way these attachments work since these photos were taken. After I determined every thing was going to work correctly the heads on the bolts have been cut off. This allows for the sliding in and out of the bolt from the tool arm itself, once the cap bolt has been loosened, to quicken the change from 10" wheel to platen.
I hope this helps as I am not a 100% certain as too what you where asking in the question.
