What you need is two anchor points behind and inline with your spindle. One that moves with the sub, and one that stays put.
You run a "dead" liner up into the sub. This is anchored to the moveable anchoring point. I like pvc for this. You start with the biggest pvc that will fit, and if you are running small D parts, then you bush it down to the closest pipe size that will work. The closer the better as you can let parts get beside others and jam it up. And the smallest tube needs to go as close as you can get to the back of the collet without rubbing when the collet is closed and empty.
Of course your part needs to be of a shape that allows it to push the previous parts.
Next you put the next larger size pipe over the dead liner. It is anchored to the sheetmetal superstructure so that it doesn't move. This tube will run up to the back of the collet closer / spindle, and then back further to an unload point.
The inner (dead) tube has to stick out the back long enough so that when the sub is all the way fwd that it doesn't pull out of the outter tube.
Now your new part just pushes the other gradually out the back, and they drop into a tray or ??? Be aware that you could git some coolant out the back as well. It takes some time to develop your system.
Any parts that will work that way, that's what we doo. If the parts won't stack w/o jamming, then we drop'm in the chip conveyor and sort later.
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Think Snow Eh!
Ox
