Centering the motor

Getting the motor to fit onto the spline is tricky since the motor lives inside the bell housing so you have to use a little mirror to see what's going on. Not only do you have to center the motor on the shaft and get it at the right angle, you also have to rotate the the shaft so that the splines line up. I can't turn the input shaft by turning the output shafts (there isn't much inside the gearbox right now) and the motor has no tailshaft so getting everything lined up is basically impossible.

I got some nylon stock from Ludowici Plastics and a friend of mine has offered to turn it on his lathe. We'll turn the outside to match the centering ring on the face of the motor and bore a hole through it to match the sleeve around the input shaft. With everything held true I only need to rotate things until the spline lines up.

My current plan for attaching the motor to the gearbox is to use this nylon centering ring to hold the motor centred while I tighten the bolts on the adapter plate. Because the motor is held centred by the nylon block, I don't have to worry machining the adapter plate to the required tolerance. If the nylon version has too much give in it then I'll have one cut from aluminium. The adapter plate will attach to the back side of the mounting ears on the motor, hopefully they're sufficiently perpendicular to the shaft. With the adapter attaching to the back side of the motor, I can use a fairly thin piece of aluminium. If I want to attach to the front surface then I would be watching an awful lot of expensive aluminium pile up under the mill.