Tools and Preparation
Very few tools are required, but assemble the following:
- 2.5mm hex bit or allen wrench (comes with unit)
- 3.0mm hex bit or allen wrench (comes with unit)
- #1 or #2 Philipps screwdriver
That's it.
Be advised that some of the screws that you will be dealing with could be put in with some type of thread locker. If you encounter a stubborn screw or bolt, apply some heat from a hair dryer or heat gun on low. Being mindful of items close by.
Move the gantry full forward and the X axis to the center. Disconnect the motor wire and limit switch wires from the back of the Z motor.
Make sure the power is off to the control box and USB cord is disconnected.
Step-by-Step Instructions
(1) Remove the 4 screws (2 either side) from the spindle motor mount. They are 3mm hex heads. Set it all aside.
(2) The next thing to do is take the screw out of the bottom of the screw drive. There's really one there! It will take a 3mm hex head. You might have to hold the Z motor knob to keep it all from turning. Remove screw and set aside.
You need to remove the above screw first step before continuing. If not and you continue to the next step you will probably find that you have nothing to keep the shaft from turning. It's easier and less damaging to do step one above first than trying to hold the shaft with pliers.
(3) Next rotate the knob so you can see the set screw in the motor to screw shaft adapter. It will take a 2.5mm hex head and it might be tight. Make sure that the hex tool is seated really well in the set screw. You might have to take a pair of pliers and grip both the short side of the wrench and the bend to get a good grip. Don't take the screw out, just loosen it a bit.
(4) Next is take out the four screws that hold the motor and mount to the top of the gantry. They will be 2.5mm hex head. The motor and mount should pull straight up. Set as aside.
If it doesn't come out easy, put your 2.5mm wrench back in the set screw and loosen it a little more. Don't remove.
(5-1-2-3) Next you can remove either the inner 4 or outer 4 screws from the Z axis plate. When your done with that set, do the next set. The outer screws are 2.5mm the inner are 3mm hex heads.
You will have to lift up the Z axis assembly to get the bottom of the screw shaft free from its hole. Might have to rotate the coupler at the top of the shaft to move the spindle mount down. Tilt the bottom forward and remove the assembly. Set it aside.
(6) If you look in the cavity of the Z axis you will see a tall narrow PCB (printed circuit board) with little push buttons on either ends of it. That piece has been the goal of this little exercise all along.
You can test to find out if the board is faulty or the limit switches are. If you press a switch one at a time and get the light on as outlined in blue at the top then that switch is OK and the board is OK for that switch. Do the other switch and see if the light comes on or not. If neither switch activates the light your switches are most likely bad. In the picture there are yellow circles around the connection points of each switch. But, you can check and see if the board is OK or not. Not that you need to know about the board if switch(s) are bad. But if you really want to check it, take a tweezers with a long pointed end and touch one on either side of a switch (where the yellow line points to the yellow circle). If the light at the top illuminates the board is good.
There are 2 small Phillips head screws to remove. Don't lose them. You can lift the board up by its top and remove.
That’s it.
(7) To reinstall all of the hardware, start from the last step and work upward. I would tighten the 2 Phillips screws in the cavity up pretty good. It would be a pain to dissemble it all again to tighten them. I would not over tighten any of the other hardware as it can weld itself to the painted surface. I found out the hard way and had to grind the tops of the face plate outer screws off to get it back apart. Just good and tight. Check the hardware occasionally and tighten as necessary.
