My snowplow robot - having trouble coupling the motor to the wheel as coupling slips. A pic of motor attached, it is a car-seat motor with a square threaded shaft. I screwed the wheel to a 3/4 in steel pipe and used an Al coupling to join them together but the screws used on the coupling keep slipping. Any ideas appreciated.

190 Rpm 12Vdc Right Angle Drive Electric Motor From Car Seats
https://www.amazon.com/gp/buyagain/...GxpY2l0Q2FuZGlkYXRlcyI6IkIwMDVJ UjFOQkEifQ==

190 Rpm 12Vdc Right Angle Drive Electric Motor From Car Seats
https://www.amazon.com/gp/buyagain/...GxpY2l0Q2FuZGlkYXRlcyI6IkIwMDVJ UjFOQkEifQ==