Newbee with Several Assembly Questions on CK.

[jwb]

I am beginning to assemble my Carve King and I have several questions and comments around the Y motor end plate assembly instructions.
1- The instructions indicate I should slide the coupler onto the NEMA 17 stepper until it stops.
The coupler I have does not have a stop in it and the stepper shaft goes all the way through. Instead I positioned the coupler with the stepper shaft just before the larger shaft bottoms out.

2- The instructions describe mounting the NEMA 17 stepper to the Y motor end plate using four M3x20 screws, washers and 8mm small spacers.
My question is why are the spacers used at all? Why not mount the stepper motor directly to the Y motor end plate?
I also noticed the 6mm spacers are almost the same diameter as the mounting holes and they are a bit misaligned when the screws are snugged up.
Why not use a fatter 8mm spacer so it's not impacted by the mounting hole? 

[Bruce]

1. The older style couple was a different design. It shouldn't be a problem as long as one side of the coupler is attached to the motor shaft and the other side is connected to drive screw. Make sure the set screws are tight. You don't want the couplers to come loose.

2. You may want to send an email on this issue to [e-mail]

[wildbill9]

I have just started putting my Carve King together and have run into the same issue with the coupling of the lead screw and stepper motor. How jwb. much of the lead screw should be into the coupling? Thanks for posting this jwb.

[Bruce]

The lead screw should be in the coupler about 1/4" deep so the set screw well hold it in place tight. The same for the motor shaft.  Once you have it all put together you may have the coupler separate a little bit.  That should be no problem.  On the Y axis make sure the set screw is tight in the pillow block end also.   

[Bruce]

I forgot to answer one of your questions:
"My question is why are the spacers used at all? Why not mount the stepper motor directly to the Y motor end plate?"

The spacers back the motor shaft out of the way to allow more lead screw length thus more travel of the gantry. Otherwise the gantry would hit the coupler before the wheels run into the end of the rail.