Prep for your AltMill

April 7, 2026

So you just purchased an AltMill 4×8, now what? While you’re waiting for your machine to show up…   

📖 Start Learning

🔌Setup Your Space

  • Install the proper electrical for 220V spindles, based on these specifications
  • Clear a work space in your shop or garage for the 4×8 machine

🛠️ Get Materials and Equipment

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  • Join our Facebook group and Forum for discussion and inspiration driven by your fellow CNC community members!

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Electrical Specifications

If you have the ATC spindle please see here for the complete electrical specifications.

Otherwise:

With a 1.5KW Spindle

We recommend allocating two 15A 110V/120V single phase circuits — one for the spindle and dust collection system, the other for the machine and a computer.

If you live in a country with 220V/240V power you should use a transformer to convert to 110V/120V.

  • To solely run the machine, you need a rating above 500W
  • To run the machine and spindle, you need a rating of 2000W, do not use GFCI breakers with spindles

With a 2.2KW Spindle

We recommend allocating at minimum one 15A 110V/120V single phase circuit for the machine and one 15A 220V/240V single phase circuit for the spindle. Computer and dust collection can go on any of the two circuits as needed.

If you are wiring a new 220V circuit, our spindle uses a NEMA 6-15P plug which follows the convention of 2x hot wires and ground.

Work Space

  • Ensure that you allocate at least 6’x12’ of space for assembly
  • When assembled, position the machine so you can load 4’x8′ sheets from the ends and sides of your machine
  • Do not put the rear end of the machine against a wall, since the Y-axis drag chain will extend back by ~14” when jogged to the back. 

Workholding

The AltMill 4×8 comes with a sturdy frame that you can mount a table surface and wasteboard to. The ¾” thick MDF sheet (purchased separately) will act as the table surface.  The wasteboard is mounted on top of the table surface, and can be fully customized to suit your application, allowing for various workholding options to be implemented. The article here explains the most common workholding options used in consumer-level CNCing. If you are planning to load 4×8 sheets, a vacuum table may be the best option as it can provide equal clamping on the entire surface of the material, minimizing warp and therefore improving the repeatability of the cuts.  

Vacuum table design by boricuahastaenlaluna (Emanuel Ortiz) on Etsy

Tools for Assembly

All specific tools needed for assembling the AltMill 4×8 are provided with the kit, however there are a couple additional things you’ll want to have with you during the build:

  • A regular woodworking clamp used to align the gantry 
  • A stool or saw horse to rest the table sections

While you’re at it, you may want to enlist a friend (or two) to help with lifting large subassemblies.

Spindle

For the AltMill, we recommend using our 1.5KW or 2.2KW Spindle Kits since the VFDs are already pre-programmed and tested under our specifications.  

However if you are looking for another option, keep in mind these following considerations.

Cutting Tools

There is a vast variety of end mills and specialized bits available for different use cases, from carving signage to cabinetry pieces. The video below explains the basic features of a cutting tool, and highlights the differences between common types of tools. Further reading on the recommended tools for specific project types can be found here.

Dust Collection 

Having proper dust collection for your 4×8 machine is essential for large-format routing, where you are cutting full sheets of material. Furthermore, it keeps dust out of the air and off sensitive machine components, removes chips and debris from cutting areas reducing the chance of rubbing or burning, and minimizes cleanup after your job. 

The general specifications for a dust collector suitable for the AltMill 4×8 are as follows:

  • 1-3hp
  • Single, double or triple bag
  • 4” diameter hose (or you can source/make your own adapter) 
  • At least 600 CFM rated flow rate