Ray LOOKS good. Here is something to consider. The piece that holds UP on the spring pack, the lower plate with the finger that slides under the pack. THis will be tricky to get the spindle in the exact position so the lever can slide under the pack AND still not have any play. ANY PLAY will cause the spindle bearings to load up as the pack is compressed. You might want to consider a push me pull me type of compressor arrangement that floats and as it is compressed both sides of the PACK are compressed at the same time. AND it puts zero load on the drawbar.
Another thought when building a drawbar is the machines always use a long 30deg angle tool holder that does NOT require any of the force of holding in the toolholder to be used to HOLD the bit as well. (;-)
Just a thought, (;-) TP
indeed it would be nice to see that, cylinder incorporated with bolted to base sviwel flange and fork clevis joining with drawbar, both strokes driven using 5/2 1/4" solenoid valve with exhaust regulators, micro plc with hmi is awesome for sorting out things like limits, rpm encoder, safety relay circuit, coolant, ..... its so obvious that tapered shanks dont need holding force
anyhow... the cylinder is not pressurised both sides simultaniously!!, 5/2 solenoid valve principle of work clearly indicate its impossible, thats why right stroke here is very important, you can always adjust it winding the clewis onto the rod bit more and properly set up cylinder's cushions you could have, i wonder if it would be possible to drive using 2 Oz carbon dioxide inserts and pressure regulator to eliminate compressor, anyhow i think that you've done an exceptionally good job, ... .. one more... cylinder fitted with reed swith could eliminate any hazards related, micro plc should also controll mains contactor