Maslow CNC Review: M2 (Upgrade Kit) & MetalMaslow

Maslow CNC Review: M2 (Upgrade Kit) & MetalMaslow

MakerMade Maslow Review: M2 Upgrade Kit

Ever since I first built built the Maslow CNC Router (Classic), I’ve been anticipating the M2 upgrade kit. I have waited this long to do a real Maslow CNC review; after months of use, I can finally speak to its capabilities.

Maslow CNC Review

Let’s get it out there in the open: I’m a big fan of the Maslow.

I wrote a thread on the Maslow forums many months back about we used it to build furniture for our new home. However, as I mentioned when building the jumpstart kit, it was still relatively hard to assemble and use. I was excited for the release of the M2 for its many improvements.

Since then, I became even more involved in the Maslow community. I am not affiliated with any hardware vendors, but have been working on making the Maslow even easier to use on the software level.

Note: both MetalMaslow and MakerMade (two manufacturers of Maslow hardware) sent me various parts, hardware, and advice throughout the writing of this post.

Maslow Improvements in M2

The MakerMade M2 is an evolution/fork of the Maslow project.

Maslow is open-source.

Vendors such as MakerMade sell hardware kits for easy assembly.

The major improvements in the M2 (upgrade-kit) are:

  • 1/8″ bits / end-mills (instead of 1/4″).
  • Metal Z-axis assembly.
  • Spring for chain tension.

Each of these are pretty great (the Z-axis has long been the biggest problem with the Maslow).

Even the last upgrade is significant:

MakerMade Maslow Review: M2 Upgrade Kit Chain Tension
The spring used to keep the chain taut, and does a much better job than the old elastic ties.

But there’s one big change I still haven’t touched on…

Maslow Arduino Due Firmware

With the M2 release, MakerMade has taken a big step towards ease-of-use. However, doing so meant they also took a step away from the rest of the Maslow community. The M2 “cuts ties” with GroundControl / WebControl (the Maslow-specific software).

Frankly, though, I’m glad for the departure. CNCjsMakerverse” is a much more full-featured, modern tool. WebControl (and GroundControl before it) were battle-tested, but clunky. They’d served the Maslow community well, but there was an opportunity to move closer to the rest of the CNC community.

I’d used the “CNCjs” web-based software before, for my SainSmart router. It is well-supported, easy to extend, and generally well-designed. The maintainer of the project, unfortunately, has become indisposed. So MakerMade forked the project into Makerverse (with his blessing). I subsequently became involved in the project, as I’ll touch upon below. What makes this all possible is the new Grbl-compliant firmware used by the M2.

The M2 uses an Arduino Due.

This board has a much better processor, and conforms to a more conventional firmware/protocol for CNC machines, known as “Grbl.”

However, I have been working with MakerMade and the Maslow community to build a “translation layer” for Makerverse, so that it can also have legacy support for the Maslow “Classic” (Arduino Mega hardware & “Holey” firmware, such as with the Jumpstart Kit).

Makerverse also now has legacy support for the Maslow Classic.

You can follow the progress of this unified software effort in the Github README.

No products found.

Unfortunately, the first versions of the Due firmware used rather simplified kinematics. It did not take into account tension & catenary effects (chain sag). What followed was a very deep rabbit-hole, as I upgraded the firmware for the Due and attempted to make Makerverse support both machines equally well. There’s a painfully long thread in the forums about this effort. tl;dr: the last bits of polish are being put on now, and by the time you read this Makerverse should be a good option for any Maslow setup.

For improved accuracy, the M2 needs a firmware upgrade.

See the README for help installing the upgrade.

This new firmware is designed to work with the new versions of Makerverse. It uses the same advanced kinematics employed by the later, more mature firmware for the Maslow Classic (Arduino Mega). This enables it to correct for rounding in the corners and other effects of chain tension.


In my time working on Makerverse, I also worked with the folks behind MetalMaslow (perhaps the other largest distributor of Maslow kits). I had the opportunity to test a completely metal sled, as well as 12′ beams and 15′ chains.

Longer beams and chains expand the workspace.

The standard 10′ beam and 12′ chains can sometimes struggle to provide enough power to the motors while also having enough weight on the sled to keep the sled flat… even with a standard 8’x4′ sheet of plywood.

There’s a spreadsheet for calculating the safety zones of the motors. It is especially useful when using larger stock, such as the 5’x5′ Baltic birch I sometimes cut. After punching in the variables in the top left, the cells describing the motors will turn red if they would over-tax the motors. You’ll find that the higher the motors are over the workspace, the more weight can be added to the sled.

I mention all this because the MetalMaslow sled, fully assembled and with a Rigid router, is 28 lbs. The design of the sled is excellent; it keeps the weight firmly and evenly pressed against the stock. Plus, the full-metal assembly guarantees that the movement of the sled (whilst the end-mill is engaged with the stock) does not cause the Z-axis to flex or bend in any way. Likewise, the 12′ metal beam has pre-drilled holes for the motors which guarantees that the sprockets are precisely evenly spaced.

In short, the benefits of a metal sled and metal beam are large. The machine is easier to calibrate and can cut larger amounts of stock.

As it happens, I received my first 3D printer just about the time I was setting up the MetalMaslow. I used this to design and print a small dust-shield with semi-transparent PETG.

Metal Maslow Review: 3d printed dust shield
MetalMaslow sled with a 3D-printed dust shield. The pen mark at the top is the middle of the stock, used for aligning X=0.


My current Maslow build is something of a hybrid. The metal sled is controlled by a MakerMade M2 chip (and the motors date all the way back to my Jumpstart Kit).

This is still relatively normal among Maslow users. It remains unclear if the community will ever converge upon a single Maslow design. But at this point, many old approaches have been discarded. There may not be a “single Maslow design,” but it’s easier than ever to get what you want/need out of a Maslow. Out-of-the-box, it’s now relatively easy to cut large pieces. If you take the time to calibrate it right and test the frame well, the Maslow can handle some pretty amazing projects.

This is why I’ve been spending my time improving the Makerverse software. With a good control layer to make the tool easier to use, I hope that the Maslow can reach an ever-wider community of DIY machinists.

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Written by
(zane) / Technically Wizardry
Join the discussion

  • thinking about getting a M2 but I’m confused about something and maybe you can help me understand. Why would I buy the M2 for $999 when I can buy the basic Maslow for $499 and add the M2 upgrade kit for $379. Is there something I’m missing. Thanks.

    • Hey Andrew! That’s a good question. I know there are some things that the upgrade kit does not have, like the upgraded sled. I’d take a close look at the photos of each product, as I’m not 100% sure that there aren’t other parts in the M2 kit that are not in the upgrade. I’d also note that the M2 is just generally a better experience; going through the Classic->M2 upgrade process will undoubtedly be more setup time on your end.

      Hope that helps!

  • Placed an order for the Metalmaslow on the 14th of March. Last email from them was over 3 weeks ago, saying it would ship by the 8th of April at the latest. It’s now May 2nd and still nothing. I would steer clear of Metalmaslow.