Drill Chuck Handle

The Print does not require any Supports regardless of whether you print it upright or upside down but I DO suggest using a Brim.

The Model is also designed to use Fuzzy Skin in the recessed Area ( Paint into it with the Bucket Tool ):

As for inserting the Drill Chuck ( I've designed it for the bigger of the two in this Sale ) the fit really depends on how the Printer is tuned and the Drive Key of the Chuck is manufactured. Unless either is grossly out of spec you should be able to insert it with enough force. If it turns out too lose I'd suggest wrapping a layer of Masking Tape around the ¼" Hex Shaft to turn it into a Press Fit.