Limits are published values, not SIMITCH machine ratings: stack ceilings and torque ceilings from Clemson patent US20180238362A1; the 6 mm no-clearance-hole ceiling and the brittle-casting caution from Semblex; the 2.0 mm pre-hole threshold and screw mass from Liu et al. 2023; the 3x draft ratio and the 2-to-4-layer range from ASSEMBLY Magazine; the thin-sheet limitation from Borgert et al. 2023; the sealed-variant rating of 1 m water column over 24 hours, and its pre-drilling requirement, from EJOT. Any real decision still needs a coupon trial on your own material.