Attaching chuck to electric motor

[python01]

Hello everyone,
I am trying to design deburr machine to clean up 19mm hole after some drilling across it. So far I found the motor, etc to drive the brush but I am stuck on the chuck and attachment of the chuck to motor shaft. Can anyone recommend any chuck and attachment ideas? The shaft diameter on the motor selected is 11.5mm with 30mm sticking out of the motor.
Thanks.

[DareBee]

forget the chuck.
Make it like a rigid shaft coupling.

[Andre' B]

Were it me I would forget the idea of building something and just find a nice used second op lathe.
HARDINGE DV-59 High Speed Shop Lathe BK model | eBay

If your time is worth anything it will be cheaper.