How to assemble a 2418 CNC mill

A CNC mill is a pretty handy tool for rapid prototyping, as well final production of parts. I was recently gifted (very generously!) a 2418 CNC Mill. Woohoo! It’s a small DIY machine for cutting/carving detailed shapes in plastic and wood.

It took a few hours to assemble. I found I needed to refer to several sets of instructions to put it together. So I’ve tried to make a more comprehensive, one-stop instruction set in this post.

The goal

Overall dimensions of the frame are 340 x 330 x 230mm – width x depth x height.

Carl-Turner-2418-Mill-Assembly-0.jpg

In the box

Carl-Turner-2418-Mill-Assembly-1
Spindle motor, Z axis assembly, fixings, X and Y stepper motors, circuitboard, USB cable and power adapter.
Carl-Turner-2418-Mill-Assembly-2
Supports, bearings, frame sections, slide rods, lead screws,
Carl-Turner-2418-Mill-Assembly-3
Table

Parts list

 

Part list 8.jpg
Image credit – Linksprite
Part list 9.jpg
Image credit – Linksprite

Tools needed

  • Allen keys (supplied). I recommend a ball-end allen key, which makes it easier.
  • Square
  • Ruler
  • Tape measure
  • Metal file
  • Paintbrush to brush off aluminium shavings left on some parts.

 

Steps

  1. Put on some good ‘flow’ tunes. My recommendation is Lost Shapes by Waveshaper.
    Screen Shot 2018-05-05 at 10.29.14 pm.png
    Lost Shapes by Waveshaper

     

  2. File the rough edges off the brackets.Carl-Turner-2418-Mill-Assembly-4.jpg
  3. Assemble base.Carl-Turner-2418-Mill-Assembly-5aCarl-Turner-2418-Mill-Assembly-5b

    Carl-Turner-2418-Mill-Assembly-5c
    You may need to file the brackets a little bit more to get the middle section square.
  4. Assemble the vertical frame (‘portal frame’).Carl-Turner-2418-Mill-Assembly-6a
    Carl-Turner-2418-Mill-Assembly-6b
    Use a square to get it all straight.
    Carl-Turner-2418-Mill-Assembly-6c
    This is where the filing you did earlier becomes important.

     

  5. Attach portal frame to base frame.
    Carl-Turner-2418-Mill-Assembly-7b
    Prepare two sets of three corner brackets
    Carl-Turner-2418-Mill-Assembly-7c
    I attached the backside and inside brackets, firmly but not fully tight, while holding a square against the frontside. This helped get it straight/aligned, before adding the front bracket.
    Carl-Turner-2418-Mill-Assembly-7d
    Do both sides and check everything is tight.

     

  6. Assemble the table.
    Carl-Turner-2418-Mill-Assembly-8a
    Note the table has 3 slots on one side and 4 on the other.
    Carl-Turner-2418-Mill-Assembly-8b
    I think the four slots are supposed to be on the top (ie the table is upside down). This may not matter, except it may be easier to fasten workpieces to the table with the four slots on the topside. I’ll flip it over when I get a chance.
    Carl-Turner-2418-Mill-Assembly-8c.jpg
    I put the four table supports at 69mm in from each edge of the frame, to centralise the table. Check the table slides smoothly along the rods. Ensure all the bolts are tight. (Note this photo also shows the y-axis lead screw and motor installed, as well as oblique supports installed, which is the next step). Put a few dots of fine machine oil on the rods.

     

  7. Install y-axis screw and motor.
    Carl-Turner-2418-Mill-Assembly-9a
    Make sure you get the lead screw of correct length.
    Carl-Turner-2418-Mill-Assembly-9b
    Screw the ‘screw rod’ into the copper nut, so it doesn’t protrude out the other side of the nut. Put a spring on the nut and put it in the front-side of the nut seat (the plastic thing under the table).
    Carl-Turner-2418-Mill-Assembly-9c
    Compress the spring until the copper nut flange almost touches the bearing seat. Now turn the screw until it comes out the other side. Don’t force it otherwise you might burr the thread or seat.
    Carl-Turner-2418-Mill-Assembly-9e
    Put the bearing seat on the screw and position it loosely on the frame.
    Carl-Turner-2418-Mill-Assembly-9d
    Attach the coupling to the stepper. Attach stepper loosely to the frame, using the plate and slide nuts. Continue screwing the screw until you’ve got enough thread clear to align it with the coupling. Centralise the bearing seat and stepper between the table supports. Tighten the slide nuts and coupling grub screws.

     

  8. Install the oblique supports.
    Carl-Turner-2418-Mill-Assembly-10a
    These were a bit tight so I reamed them out by hand with a 5mm drill bit.
    Carl-Turner-2418-Mill-Assembly-10b
    Use slide nuts and 5mm bolts to fasten. Don’t over tighten as you could damage the plastic part.

     

  9. Install Z/X axis.Carl-Turner-2418-Mill-Assembly-11aCarl-Turner-2418-Mill-Assembly-11bCarl-Turner-2418-Mill-Assembly-11cCarl-Turner-2418-Mill-Assembly-11d
    Carl-Turner-2418-Mill-Assembly-11e.jpeg
    Assemble the bolts and slide nuts loosely on the support pedestals. Slide the support pedestals onto the smooth rods. Put the assembly onto the portal frame, and tighten the top two bolt just enough to hold it in place while you align things.

    Align the top support pedestals to be flush with the top of the portal frame (use a square). Tighten the grub screws on the top rod. Align the bottom pedestals to be 26mm from the top ones and tighten. Tighten grub screws on bottom rod. Check the ZX assembly slides smoothly from one end to the other. When it’s good tighten up all the bolts and check again.

    Install the stepper and idler bearing, ensuring everything is aligned.

  10. Install the circuitboard, motor and wiring.
    Carl-Turner-2418-Mill-Assembly-12a
    (wiring and motor spindle not shown)
    Carl-Turner-2418-Mill-Assembly-12b
    Attach the heat sinks to the stepper drivers.
    Carl-Turner-2418-Mill-Assembly-12c
    Attach the circuitboard to the rear of the frame, using the plastic spacers and slide nuts.
    Carl-Turner-2418-Mill-Assembly-12d
    Slide the spindle motor into the ZX axis assembly. Tighten up the bolt, not too tight as you might damage the plastic part. Use the remaining brass coupling to attach cutting tools to the spindle motor.
    Carl-Turner-2418-Mill-Assembly-12e
    Install the wiring, noting that each set of wires has different types of connectors at either end. Keep the wiring tidy with zip ties. Ensure you allow enough slack on the Z and spindle wires for it to move while milling.

     

  11. That’s it!Carl-Turner-2418-Mill-Assembly-0 

2 thoughts on “How to assemble a 2418 CNC mill

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