You need an actual desktop CNC mill — not the form of glorified CNC router that’s solely good for wooden and plastic. The Shariff DMC2 Mini guarantees to supply that at an affordable value, however does it reside as much as that promise? Let’s discover out!
Let’s speak rigidity
Machining, together with CNC milling, is all about rigidity. You will get away with mediocre rigidity on a lathe in case you don’t want excessive precision or quick materials removing, as single-point slicing doesn’t require a lot pressure. However an finish mill makes a whole lot of contact with the fabric and there may be often fairly a little bit of leverage concerned, so mills must be very inflexible.
My guide mill is about seven toes tall and three,000 kilos (do not decide my messy storage)
For that motive, each industrial CNC mill on the planet is huge and heavy — there merely isn’t a sensible substitute for mass. And for a similar motive, most desktop CNC mills wrestle to machine steel.
However that doesn’t imply it’s not possible to machine steel on a desktop machine. Intelligent engineering, sturdy construction, and the right machining methods go a great distance. Shariff DMC’s objective has been to realize that at an inexpensive value and the DMC2 Mini is the present pinnacle of these efforts.
The DMC2 Mini
The unique Shariff DMC1
The unique Shariff DMC1 launched by way of Kickstarter again in 2019. Although it didn’t fairly attain the complete funding objective, it was reportedly a great machine. Then, a few years later, Shariff launched the DMC2 on Kickstarter. It was improved in each method and that marketing campaign reached greater than 15 instances its funding objective.
Most just lately, a few yr in the past, Shariff introduced the DMC2 Mini. There wasn’t a Kickstarter marketing campaign for that and as a substitute Shariff began promoting the machine on to clients.
The DMC2 Mini has a smaller working space, a smaller general dimension, and weighs lower than the unique DMC2. Nevertheless it wouldn’t be correct to say that it’s only a lesser mannequin. Omar Shariff, the person behind the corporate, utterly reengineered the DMC2 Mini to make each manufacturing and meeting extra streamlined.
Apart from the smaller working space, there aren’t actually any main compromises with the DMC2 Mini in comparison with the DMC2. However it’s considerably extra inexpensive and likewise quite a bit simpler to place collectively.
There’s a lot to love concerning the DMC2 Mini:
- 12×7×5.5” working space
- Decision all the way down to 0.0014mm (with microstepping)
- Closed-loop steppers
- 3HP (2.2kW) 24,000 RPM spindle
- Giant ER20 collet
- Device peak setter and XY probe
- 120V (or 220V) single-phase family energy
- A built-in flood coolant system
- A built-in central oiling system
- An accessible MPG handwheel
- Compatibility with Mach3
- Claimed tolerances beneath 0.01mm (extra on this later)
The Shariff DMC2 Mini has been accessible both as a equipment or assembled. Nonetheless, Omar has stated that only a few folks buy the assembled machine. As a substitute, nearly everybody chooses to save cash with the equipment. That equipment prices $2,500, which is a really enticing value.
After all, the equipment does require meeting, so let’s speak about that!
Assembling the DMC2 Mini
Placing collectively a DMC2 Mini from the equipment isn’t a job for the faint of coronary heart. Nothing in any respect comes pre-assembled and it’s important to do every part your self.
The Shariff DMC2 Mini equipment arrives in a number of packing containers
I’m not inexperienced by any means, however even I used to be a bit intimidated by the venture. So, I had a pal come and stick with me for an extended weekend to assist me sort out the meeting. All advised, I’d estimate that it took the 2 of us round 20 hours to complete the job. We weren’t precisely dashing, however we weren’t lollygagging both.
Pleased that we pulled it off!
The excellent news is that the directions offered by Shariff are very, superb. There are photos and written descriptions for each single step. With a few small exceptions that required some thought, the directions had been clear sufficient for us to comply with simply.
An instance from the meeting directions, that are very clear.
That stated, we did run into a few hiccups. When placing collectively the metal tubes that type the body, we had bother with the match of one of many items. It didn’t wish to line up appropriately and required some critical pressure to get into place.
One of many body rails was tough to get into place.
Associated to that, we additionally had bother with the Y-axis rails being too far aside. They had been a full millimeter too large and that made it not possible to mount the mattress plate on the bearing blocks. Our answer was to drill out the mattress plate’s mounting holes to achieve simply sufficient additional wiggle room to get the bolts by way of. I don’t suppose there have been any in poor health results from that, however it’s best to understand that the meeting course of would possibly require some massaging of the elements.
Drilling out the aluminum mattress mount to widen the holes.
Making the mattress mount match.
I additionally discovered the sealing course of to be irritating. The enclosure is manufactured from sheet steel and you have to add silicone caulk to all the joints, seams, and screw holes to stop coolant from leaking. There are a whole lot of areas to deal with and it’s a problem to get a great seal on all of them. I ended up having a whole lot of leaks, which I’ll speak extra about later on this evaluate.
All of that stated, I used to be impressed by the engineering of the DMC2 Mini and felt just like the meeting went fairly nicely. The hiccups I discussed are usually inevitable with kits like these and I didn’t discover them to be significantly problematic.
The ending step is so satisfying!
A phrase about machining methods
With an enormous industrial VMC, you’ll be able to seize a large 1” diameter finish mill, crank the coolant circulate up, and plow by way of a full-depth slot reduce with brute pressure. However a small desktop mill just like the Shariff DMC2 Mini requires much more finesse.
Particularly, the DMC2 Mini likes HSM (Excessive Pace Machining) methods. Meaning working at excessive velocity, excessive feed, and really small stepover. The objective is to make use of the size of the top mill’s flutes whereas transferring in a short time, however with out stepping over a lot — which might exceed the spindle’s energy and likewise trigger deflection.
Spittin’ chips at excessive velocity.
HSM has grow to be a very talked-about technique, even for these huge VMCs, as a result of it’s environment friendly, extends instrument life, and yields good finishes. Nevertheless it does require much more consideration and fine-tuning of toolpaths and parameters.
Fortunately, Shariff gives profiles for Autodesk Fusion’s CAM. These can be found for all the finish mills Shariff presents, for working with each aluminum and metal. I discovered these profiles to be fairly nicely optimized and largely caught to them.
Software program and setup
You need to use no matter CAM software program you want (I used Autodesk Fusion), however to run the machine you’ll in all probability wish to stick with Mach3. That’s what Shariff recommends and gives directions for.
Establishing Mach3 on an previous Microsoft Floor
I put in Mach3 on an previous Microsoft Floor that I had accumulating mud and it labored nicely sufficient for the job. After following the directions for the essential configuration and making certain that the motor instructions/steps are all right, I took Shariff’s recommendation and put in another interface that’s way more nice than the default Mach3 interface.
After that, you will have to configure and calibrate the probes. There may be one for Z (setting the instrument peak relative to the fabric or your reference) and one other for locating your X and Y references (often the edges of the fabric). It takes a great half-hour to try this utilizing a multimeter, as you have to discover the precise offsets to your assembled machine. However it’s nicely well worth the effort, because the probes make it straightforward to arrange jobs sooner or later.
Going through the mattress good and flat.
Lastly, you’ll must face the mattress to get it flat and parallel to the machine’s XY aircraft. Shariff sells a 10mm insert mill that makes that job (and all going through jobs) fast. It leaves an incredible end. With the mattress confronted, you’ll be able to bore and faucet mounting holes to your vise (there’s a template in case you get the vise from Shariff).
Fill a bucket with coolant, drop your pump into that, and also you’re able to go.
Testing
As common, my testing course of was unstructured. I merely tried milling an entire bunch of aluminum and metal elements to see what sort of outcomes I may get.
First take a look at in 1018 metal.
As a lot as potential, I used finish mills from the set that Shariff sells. They’re fairly respectable and work with the Autodesk Fusion profiles offered by Shariff.
Nonetheless, I did find yourself breaking the 2 largest three-flute finish mills and needed to change to some others that I had readily available. These broke as a result of the Z-axis motor cable was barely unfastened, which resulted in collisions when the motor didn’t transfer as predicted. That was fully my fault and easily reseating the cable plug solved the issue.
Damaged finish mills as a result of my Z axis motor cable was unfastened (my fault)
I used to be impressed with the DMC2 Mini’s capabilities and it was genuinely fairly unbelievable to see it zip round a block of metal with none wrestle. The flood coolant is unbelievable and actually helps to clear chips and hold temperature down. I feel that coolant system is among the largest benefits the DMC2 Mini has over different hobbyist machines. And the floor finishes I used to be capable of get had been actually nice.
Nonetheless, I had quite a lot of bother reaching the claimed tolerances and we have to speak about that.
Tolerances
All desktop mills have bother attaining nice tolerances, for the explanations I defined originally of this evaluate. However the 0.01mm that Shariff claims is feasible is definitely very, superb. I used to be actually hoping to get near that, however sadly wasn’t capable of.
0.01mm tolerances can be unbelievable, however I could not attain that.
It wasn’t for a scarcity of making an attempt, as I spent months making an attempt to get one of the best outcomes and tried every part alongside the way in which. However one of the best I may get was someplace round 0.1mm.
To be clear, that’s nonetheless adequate for the overwhelming majority of hobbyist wants and I wouldn’t name it unhealthy. We’re speaking about milling metal on a $2,500 machine that solely weighs just a little greater than 100lbs. Nevertheless it wasn’t pretty much as good as I had hoped.
I ran this take a look at a dozen instances.
Initially, I assumed the problem was my CAM programming and so I spent take a look at after take a look at making an attempt to excellent that. When that didn’t carry a lot enchancment, I started trying to find potential points with the machine.
I made certain all the nuts and bolts had been good and tight. I used a dial indicator to ensure there wasn’t any spindle or instrument runout. I verified that there was just about zero backlash. I checked to be sure that every axis was transferring the gap it ought to with out load. I lowered the acceleration in case the steppers had been skipping. I even switched computer systems, in case that Floor was having bother dealing with the processing.
Testing spindle and power runout, with zero perceivable motion on the needle.
However in any case of that, the one clarification I’m left with is that the machine’s body is flexing a tiny bit. As I stated, rigidity is every part in machining.
I can truly measure that flex by attaching the dial indicator to the vise and placing the stylus in opposition to the top mill shaft. If I put some pressure on the spindle mount, the dial strikes. In actual fact, if I elevate one of many machine’s toes, the dial strikes.
With some muscle, I may flex the machine sufficient to get important needle motion.
Now, it’s fully potential that that is my fault and that one thing isn’t tightened down sufficient someplace on the machine. However I went again over each bolt I may get to and every part is torqued down.
I additionally wish to level out that I feel mounting the machine’s toes to a sturdy stand or workbench would assist. Sadly, that isn’t an possibility with what I’ve at present received in my workshop, however that may successfully reinforce the construction and supply extra rigidity.
However honesty is my first precedence after I evaluate one thing and, as a lot as I just like the Shariff DMC2 Mini, I’ve to be upfront about my expertise.
Coolant woes
One other main headache was coolant leaking. There have been many factors that weren’t fairly sealed sufficient and would drip coolant. I’d plug up one leak only for one other to pop up.
Coolant leaks had been a headache.
I additionally actually dislike the coolant “trough” on the again of the machine, the place the coolant flows from the enclosure right into a tube that goes again into the coolant bucket. That’s truly the one a part of your complete machine that I feel was poorly designed. If a chip “dam” varieties or there’s a kink within the hose, the coolant rapidly backs up within the trough and overflows.
My 3D-printable “trough” alternative.
I ended up designing a 3D-printable alternative for that trough that largely solves the issue. It has larger partitions, a steeper angle, and accommodates a extra inflexible tube that isn’t susceptible to kinking.
The brand new “trough” on the DMC2 Mini.
The coolant system may be very helpful, so I counsel doing one thing related in case you even have issues with the trough. You possibly can discover my design right here if you wish to print it.
Oiler points
I additionally had issues with the oiler. It’s a operated by hand central system that sends oil down traces to every of the bearing blocks, which is a particularly good concept. Oiling a machine’s factors is a large ache, so I used to be actually excited that the DMC2 Mini has a central oiler.
The manually function oil and manifold.
However mine appeared to actually wrestle to get oil by way of the traces and to the bearings. It was very gradual to feed and pushed much more oil by way of some traces than others. I feel the issue is both the oiler itself or the manifold block that connects it to the assorted traces. It does work, simply not in addition to I would love.
Messy energy provides
The DMC2 Mini itself may be very tidy, but it surely seems like Shariff forgot to complete issues as the ability provides and spindle VFD are utterly unfastened and unenclosed.
Every thing is so tidy, besides the ability provides and VFD.
An proprietor can definitely construct their very own enclosure for these, however I’d have appreciated to have seen an enclosure offered — or at the very least information to 3D-print one or one thing.
Sufficient complaining
It’d look like I’ve detrimental emotions concerning the Shariff DMC2 Mini, however I actually don’t. My trustworthy opinion is that it’s a good desktop CNC mill. That’s very true when you think about the value.
Apart from the tolerance issues, the problems I listed are largely issues of comfort and might be addressed by homeowners with out an excessive amount of bother or expense.
The coolant leaking is solvable with cautious sealing and a alternative trough — or simply relaxation your complete machine in a tray, like the sort you’d put a water heater on.
My oiler (or the manifold) was in all probability simply faulty and it’s nonetheless usable as it’s.
The unfastened energy provides and VFD might be put in a home made enclosure.
On the subject of tolerances, I feel most hobbyists would discover what I used to be attending to be acceptable. People who don’t ought to have the ability to enhance issues by being very thorough throughout meeting or by fixing the machine to a sturdy stand.
To that finish, I don’t suppose Shariff is being dishonest about 0.01mm being one thing that some homeowners can obtain. 0.02–0.04mm undoubtedly feels real looking, even when I couldn’t get there.
Remaining ideas
So, the large query: must you purchase a Shariff DMC2 Mini?
I feel the reply is “sure,” in case you have the best expectations, together with a willingness to place the time into meeting and getting essentially the most out of the machine.
There are desktop CNC mills in the marketplace which might be way more “turnkey.” However they’re dearer and/or much less succesful. Should you’re acquainted with the 3D printing market, you would possibly wish to consider the DMC2 Mini like a Voron: a machine for individuals who need a whole lot of potential and are completely satisfied to get their palms soiled to succeed in that potential.
At a value of $2,500 for the equipment, I imagine that, greenback for greenback, the Shariff DMC2 Mini is one of the best desktop CNC mill in the marketplace.
