Quill collar for 1220XL
We've been working on making a new collar to fit around the mill quill on our Smithy CB1220XL. We started with a 4" diameter by 3/4" long piece of 6061 aluminum. After a bunch of facing / turning / boring / milling / drilling / tapping / sawing operations, we've successfully made the part. We had great results with lathe accuracy, able to get diameters finished to within roughly +/- 0.002" of target.
The outer diameter is arbitrary. The larger bore diameter must fit snugly around the quill collar for a press-fit -- it is then tightened with the two hex-cap screws as shown. The smaller bore through the piece must clear the rotating spindle, but must remain close so as to provide a chip shield for the thrust bearings just within the collar. We ran into lots of issues with work planning, some of which were due to the reduced work volume of the machine, but most of which were simply due to our original paper design taking insufficient consideration of things like obstruction by the drill chuck, tool cutting lengths, etc. But it works! It goes on snug and is quickly tightened via the two screws. This replaces a plastic cap included with the machine. However, this version gives us the opportunity to add a Z-axis digital read out (DRO)... stay tuned!
