This is the first prototype of a door actuator. I used a 298:1 gear motor and 10-24 threaded rod. I drilled out the black delrin and threaded the first 1/2" to match the 10-24 all thread. Then I clearance drilled the remainder of the delrin to the threads only engage the first part of the delrin, otherwise there would be a lot of drag. The hard part is the deep clearance drilling of the delrin, you are limited by how deep you can drill. I did all this on the lathe. The motor mount is a section of aluminum channel with a set screw holding the motor.
I made a coupler/adapter to attach the threaded Rod to the motor. It is drilled to fit the 10-24 rod on one end and the smaller motor shaft on the other end. Then I installed two set screws to fasten each end.
https://youtu.be/ttvLRUiM-M4
Jim