sentro knitting machine drill adapter

this is a drill adapter for a knitting machine that was inspired by

https://www.thingiverse.com/thing:4782036?fbclid=IwAR3Eloxqd_UhzOG45hk8NKLG-NytHavjqOe2tEqGdV6EFTXMXZU4TyhL0Tw

except mine is optimized for 3d printing and requires no support and is ready to go right off the machine. it uses a 3/8 inch square bit (10mm x 10mm square opening)