The Maker’s Toolbox: Shariff DMC2 Mini CNC Mill Review

You want a real desktop CNC mill — not the kind of glorified CNC router that is only good for wood and plastic. The Shariff DMC2 Mini promises to provide that at a reasonable price, but does it live up to that promise? Let’s find out!

Let’s talk rigidity

Machining, including CNC milling, is all about rigidity. You can get away with mediocre rigidity on a lathe if you don’t need high precision or fast material removal, as single-point cutting doesn’t require much force. But an end mill makes a lot of contact with the material and there is usually quite a bit of leverage involved, so mills need to be very rigid.

For that reason, every industrial CNC mill on the planet is big and heavy — there simply isn’t a practical substitute for mass. And for the same reason, most desktop CNC mills struggle to machine metal.

But that doesn’t mean it is impossible to machine metal on a desktop machine. Clever engineering, sturdy structure, and the proper machining techniques go a long way. Shariff DMC’s goal has been to achieve that at an affordable price and the DMC2 Mini is the current pinnacle of those efforts.

The DMC2 Mini

The original Shariff DMC1 launched through Kickstarter back in 2019. Though it didn’t quite reach the full funding goal, it was reportedly a good machine. Then, a couple of years later, Shariff launched the DMC2 on Kickstarter. It was improved in every way and that campaign reached more than 15 times its funding goal.

Most recently, about a year ago, Shariff announced the DMC2 Mini. There wasn’t a Kickstarter campaign for that and instead Shariff started selling the machine directly to customers.

The DMC2 Mini has a smaller working area, a smaller overall size, and weighs less than the original DMC2. But it wouldn’t be accurate to say that it is just a lesser model. Omar Shariff, the man behind the company, completely reengineered the DMC2 Mini to make both manufacturing and assembly more streamlined.

Other than the smaller working area, there aren’t really any major compromises with the DMC2 Mini compared to the DMC2. But it is significantly more affordable and also a lot easier to put together.

There is a lot to like about the DMC2 Mini:

• 12×7×5.5” working area
• Resolution down to 0.0014mm (with microstepping)
• Closed-loop steppers
• 3HP (2.2kW) 24,000 RPM spindle
• Large ER20 collet
• Tool height setter and XY probe
• 120V (or 220V) single-phase household power
• A built-in flood coolant system
• A built-in central oiling system
• An available MPG handwheel
• Compatibility with Mach3
• Claimed tolerances below 0.01mm (more on this later)

The Shariff DMC2 Mini has been available either as a kit or assembled. However, Omar has said that very few people purchase the assembled machine. Instead, almost everyone chooses to save money with the kit. That kit costs $2,500, which is a very attractive price.

Of course, the kit does require assembly, so let’s talk about that!

Assembling the DMC2 Mini

Putting together a DMC2 Mini from the kit isn’t a job for the faint of heart. Nothing at all comes pre-assembled and you have to do everything yourself.

I am not inexperienced by any means, but even I was a bit intimidated by the project. So, I had a friend come and stay with me for a long weekend to help me tackle the assembly. All told, I would estimate that it took the two of us around 20 hours to finish the job. We weren’t exactly rushing, but we weren’t lollygagging either.

The good news is that the instructions provided by Shariff are very, very good. There are pictures and written descriptions for every single step. With a couple of small exceptions that required some thought, the instructions were clear enough for us to follow easily.

That said, we did run into a couple of hiccups. When putting together the steel tubes that form the frame, we had trouble with the fit of one of the pieces. It didn’t want to line up correctly and required some serious force to get into position.

Related to that, we also had trouble with the Y-axis rails being too far apart. They were a full millimeter too wide and that made it impossible to mount the bed plate on the bearing blocks. Our solution was to drill out the bed plate’s mounting holes to gain just enough extra wiggle room to get the bolts through. I don’t think there were any ill effects from that, but you should keep in mind that the assembly process might require some massaging of the parts.

I also found the sealing process to be frustrating. The enclosure is made of sheet metal and you need to add silicone caulk to all of the joints, seams, and screw holes to prevent coolant from leaking. There are a lot of areas to treat and it is a challenge to get a good seal on all of them. I ended up having a lot of leaks, which I’ll talk more about later in this review.

All of that said, I was impressed by the engineering of the DMC2 Mini and felt like the assembly went pretty well. The hiccups I mentioned tend to be inevitable with kits like these and I didn’t find them to be particularly problematic.

A word about machining techniques

With a big industrial VMC, you can grab a massive 1” diameter end mill, crank the coolant flow up, and plow through a full-depth slot cut with brute force. But a small desktop mill like the Shariff DMC2 Mini requires a lot more finesse.

Specifically, the DMC2 Mini likes HSM (High Speed Machining) techniques. That means running at high speed, high feed, and very small stepover. The goal is to use the length of the end mill’s flutes while moving very quickly, but without stepping over much — which would exceed the spindle’s power and also cause deflection.

HSM has become a very popular strategy, even for those big VMCs, because it is efficient, extends tool life, and yields nice finishes. But it does require a lot more consideration and fine-tuning of toolpaths and parameters.

Luckily, Shariff provides profiles for Autodesk Fusion’s CAM. Those are available for all of the end mills Shariff offers, for working with both aluminum and steel. I found those profiles to be pretty well optimized and mostly stuck to them.

Software and setup

You can use whatever CAM software you like (I used Autodesk Fusion), but to run the machine you’ll probably want to stick to Mach3. That is what Shariff recommends and provides instructions for.

I installed Mach3 on an old Microsoft Surface that I had collecting dust and it worked well enough for the job. After following the instructions for the basic configuration and ensuring that the motor directions/steps are all correct, I took Shariff’s advice and installed an alternative interface that is much more pleasant than the default Mach3 interface.

After that, you will need to configure and calibrate the probes. There is one for Z (setting the tool height relative to the material or your reference) and another for finding your X and Y references (usually the sides of the material). It takes a good 30 minutes to do that using a multimeter, as you need to find the exact offsets for your assembled machine. But it is well worth the effort, as the probes make it easy to set up jobs in the future.

Finally, you’ll need to face the bed to get it flat and parallel to the machine’s XY plane. Shariff sells a 10mm insert mill that makes that job (and all facing jobs) quick. It leaves a great finish. With the bed faced, you can bore and tap mounting holes for your vise (there is a template if you get the vise from Shariff).

Fill a bucket with coolant, drop your pump into that, and you’re ready to go.

Testing

As usual, my testing process was unstructured. I simply tried milling a whole bunch of aluminum and steel parts to see what kind of results I could get.

As much as possible, I used end mills from the set that Shariff sells. They’re pretty decent and work with the Autodesk Fusion profiles provided by Shariff.

However, I did end up breaking the two largest three-flute end mills and had to switch to some others that I had on hand. Those broke because the Z-axis motor cable was slightly loose, which resulted in collisions when the motor didn’t move as predicted. That was entirely my fault and simply reseating the cable plug solved the problem.

I was impressed with the DMC2 Mini’s capabilities and it was genuinely pretty incredible to see it zip around a block of steel without any struggle. The flood coolant is fantastic and really helps to clear chips and keep temperature down. I think that coolant system is one of the biggest advantages the DMC2 Mini has over other hobbyist machines. And the surface finishes I was able to get were really great.

However, I had a great deal of trouble reaching the claimed tolerances and we need to talk about that.

Tolerances

All desktop mills have trouble attaining great tolerances, for the reasons I explained at the beginning of this review. But the 0.01mm that Shariff claims is possible is actually very, very good. I was really hoping to get close to that, but sadly wasn’t able to.

It wasn’t for a lack of trying, as I spent months trying to get the best results and tried everything along the way. But the best I could get was somewhere around 0.1mm.

To be clear, that is still good enough for the vast majority of hobbyist needs and I wouldn’t call it bad. We’re talking about milling steel on a $2,500 machine that only weighs a little more than 100lbs. But it wasn’t as good as I had hoped.

Initially, I thought the issue was my CAM programming and so I spent test after test trying to perfect that. When that didn’t bring much improvement, I began searching for potential issues with the machine.

I made sure all of the nuts and bolts were nice and tight. I used a dial indicator to make sure there wasn’t any spindle or tool runout. I verified that there was virtually zero backlash. I checked to make sure that each axis was moving the distance it should without load. I lowered the acceleration in case the steppers were skipping. I even switched computers, in case that Surface was having trouble handling the processing.

But after all of that, the only explanation I’m left with is that the machine’s frame is flexing a tiny bit. As I said, rigidity is everything in machining.

I can actually measure that flex by attaching the dial indicator to the vise and putting the stylus against the end mill shaft. If I put some force on the spindle mount, the dial moves. In fact, if I lift one of the machine’s feet, the dial moves.

Now, it is entirely possible that this is my fault and that something isn’t tightened down enough somewhere on the machine. But I went back over every bolt I could get to and everything is torqued down.

I also want to point out that I think mounting the machine’s feet to a sturdy stand or workbench would help. Unfortunately, that isn’t an option with what I’ve currently got in my workshop, but that would effectively reinforce the structure and provide additional rigidity.

But honesty is my first priority when I review something and, as much as I like the Shariff DMC2 Mini, I have to be upfront about my experience.

Coolant woes

Another major headache was coolant leaking. There were many points that weren’t quite sealed enough and would drip coolant. I’d plug up one leak just for another to pop up.

I also really dislike the coolant “trough” on the back of the machine, where the coolant flows from the enclosure into a tube that goes back into the coolant bucket. That is actually the one part of the entire machine that I think was poorly designed. If a chip “dam” forms or there is a kink in the hose, the coolant quickly backs up in the trough and overflows.

I ended up designing a 3D-printable replacement for that trough that mostly solves the problem. It has higher walls, a steeper angle, and accommodates a more rigid tube that isn’t prone to kinking.

The coolant system is very useful, so I suggest doing something similar if you also have problems with the trough. You can find my design here if you want to print it.

Oiler issues

I also had problems with the oiler. It is a manually operated central system that sends oil down lines to each of the bearing blocks, which is an extremely good idea. Oiling a machine’s points is a huge pain, so I was really excited that the DMC2 Mini has a central oiler.

But mine seemed to really struggle to get oil through the lines and to the bearings. It was very slow to feed and pushed a lot more oil through some lines than others. I think the problem is either the oiler itself or the manifold block that connects it to the various lines. It does work, just not as well as I would like.

Messy power supplies

The DMC2 Mini itself is very tidy, but it feels like Shariff forgot to finish things as the power supplies and spindle VFD are completely loose and unenclosed.

An owner can certainly build their own enclosure for those, but I would have liked to have seen an enclosure provided — or at least files to 3D-print one or something.

Enough complaining

It might seem like I have negative feelings about the Shariff DMC2 Mini, but I really don’t. My honest opinion is that it is a good desktop CNC mill. That’s especially true when you consider the price.

Aside from the tolerance problems, the issues I listed are mostly matters of convenience and can be addressed by owners without too much trouble or expense.

The coolant leaking is solvable with careful sealing and a replacement trough — or just rest the entire machine in a tray, like the kind you’d put a water heater on.

My oiler (or the manifold) was probably just defective and it is still usable as it is.

The loose power supplies and VFD can be put in a homemade enclosure.

When it comes to tolerances, I think most hobbyists would find what I was getting to be acceptable. Those that don’t should be able to improve things by being very thorough during assembly or by fixing the machine to a sturdy stand.

To that end, I don’t think Shariff is being dishonest about 0.01mm being something that some owners can achieve. 0.02–0.04mm definitely feels realistic, even if I couldn’t get there.

Final thoughts

So, the big question: should you buy a Shariff DMC2 Mini?

I think the answer is “yes,” if you have the right expectations, along with a willingness to put the time into assembly and getting the most out of the machine.

There are desktop CNC mills on the market that are much more “turnkey.” But they’re more expensive and/or less capable. If you’re familiar with the 3D printing market, you might want to think of the DMC2 Mini like a Voron: a machine for people who want a lot of potential and are happy to get their hands dirty to reach that potential.

At a price of $2,500 for the kit, I believe that, dollar for dollar, the Shariff DMC2 Mini is the best desktop CNC mill on the market.