Introduction: Mounting the MakerMade Z-axis on M2 Sled
In the Summer of 2020, the folks at MakerMade announced their improvements to the classic Maslow CNC design. They called the new design "M2."
I had already built myself a Maslow CNC from a kit and a Ridged R2901 router. While my son and I worked on a mixed-media art project and a furniture project, it became pretty obvious just how unreliable the original Z-axis mechanism was. It was a no-brainer to buy a better Z-axis stage, so I became one of their "M2 Upgrade" pre-order customers.
(The upgrade kit didn't come with a pre-drilled M2 sled, but luckily I managed to barter for one.)
Here is the problem that this Instructable will help you with: The Z-axis assembly is fastened to the sled using six screws and six t-nuts. Unfortunately the t-nuts are free to slide inside the two extruded aluminum channels. So how the heck are you supposed to keep the t-nuts from sliding around?
Short answer: you carefully tape down the t-nuts with masking tape so they are perfectly lined up and stay put long enough to screw into them. Here I'll take you through how you do that with a minimum of frustration.
Step 1: Mark the Tape in 2 Inch Intervals
With a ruler, mark off three lines spaced 2 inches apart. I called them 0", 2", and 4".
I used wide masking tape, but if yours is narrow, you can just do this twice and skip the next step.
Step 2: Cut the Tape in Half
Step 3: Cut Notches in the Tape
You want the screw holes in the t-nuts to be clear of tape and adhesive, so cut notches in the tape, and fold them back under.
Step 4: Find the Center Reference of Each Aluminum Channel
There is a handy (unrelated) screw hole in the middle of the channel. Find that. It's going to be your center reference.
Step 5: Center the Middle T-nut Over the Center Reference
Step 6: Put the Tape Down With the 2" Mark in the Middle and Position All the T-nuts
Slide the three t-nuts so they are exactly centered on the 0", 2", and 4" marks. Do this for both channels.
Step 7: Press the Tape Down So It Holds All the T-nuts in Place
Do this for both channels.
Step 8: Position the Sled, Bottom Side Up, Over the Z-axis Assembly
You are going to have to eyeball the six screw holes so they line up over the six t-nuts. If you're lucky, the t-nuts won't move while you are doing this.
Step 9: (optional) If One of the T-nuts Has Moved...
...and you can't get it back into place with the screw...
Stick a nail, wire, or small screwdriver into the hole to re-center the t-nut, if you think it has wiggled out of place.
I was lucky, and they all stay put.
Try turning the screw backwards until it falls into the counter-sunk hole.
If the screw sticks out of the sled, it probably is not lined up with the t-nut.
Step 10: LOOSELY Screw in the Six Screws
Once everything is lined up, you can just screw in the six screws.
I would use a regular screw driver, not an electric screwdriver.
But leave the screws very loose. You need to be able to lift the Z-axis assembly a bit in the next step, and later slide it back and forth to align the router with the big center hole in the sled.
Step 11: Remove Tape: Part 1
Turn the sled over.
Pull up on the Z-axis assembly while you...
Step 12: Remove Tape: Part 2
... Carefully remove the two pieces of tape under the Z-axis using tweezers.
And you're done!