DMC2 Mini Mill - build and review

[Mike R]

So I decided to buy a new machine. Its going to arrive hopefully tomorrow and I'll pick it up from the UPS store.

Its a DMC2 Mini Mill from https://shariffdmc.com

A bit of background storytelling on why I want (need?) this machine.

I converted a ZAY 12Z mill (RF45 type) to CNC back in 2010.

What I didn't know about CNC vs what I thought I knew about CNC machines - well you can guess, but I sure did learn a lot over the years.

Long story short - it works, has had many updates, but still leaves me wanting a machine that won't eat 3mm endmills just by looking at them. i.e. it can't do small stuff due to backlash, yes even with backlash compensation. Its just too sloppy and variable depending on where in its travel it is. (single ball nuts), and the spindle speed is too low.
I don't have it in me to tear it all apart and replace the ballscrews and nuts (and probably mounts) with new double ball nuts. Maybe once I have a 2nd milling machine...

I want to machine small things - little IC engines, bits for steam locomotives, etc. A desktop CNC seems to fit the bill there. And I'd been looking at the various router options but didn't think a cnc router was what I really wanted.
I helped someone spec out and build a Taig CNC mill just 2 years ago, they bought the Taig 5019CR micro mill and I helped them through the stepper motor and control selection and setup. Its a nice little machine but still seemed to be missing something.

And then I saw it. Youtube knew what I needed in my life - a gapping hole in my wallet and another project I don't have enough time for.

Things that this machine ticked boxes for me, that seemed to be missing in other machines:
1. enclosure - keeps most chips in. I know it won't keep them all in, but reducing the area impacted is nice.
2. proper way covers on Y axis ways and ballscrew. X and Z are elevated so not as directly impacted.
3. ability to run coolant. (coolant pump included)
4. proper oiling system
5. proper high speed variable speed spindle (ER20)
6. Claimed ability to run very small cutters / small resolution (0.1mm end mill shown in youtube video )
7. Modest price* $3400 Cad plus shipping ($250) and taxes. Not thrilled with the shipping but I'd be out a full day from work and $100 in gas to go pick it up (5hr drive each way). And it still needs a controller* - more on that later, but for the price it seems like I'd be most of the way there in terms of dollars spent if I tried to build this myself from parts I order off of Amazon or AliExpress (that thought did cross my mind several times).

Additionally - this has a real human admitting their 1st design left some room for improvement and using the feedback to improve the offering and explaining why its a better design (not just stating "new and improved")

Regardless - I'm now on this path so we'll see how it goes. Hopefully I can provide a timely update on my progress as I build and then test this thing out and my ramblings will be of use to someone else.

Mike

 

[Mcgyver]

That is an interesting machine, I'm looking forward to seeing how it works out.

Part of me wants to pull the trigger, the other part is doubtful about linear bearing quality, run out of collets, spindle quality etc. I also am curious how they create flatness (a linear bearing doesn't create flatness, it will bend to whatever its bolted do).

They are local for me, i wonder if they'd demo it? I found this overview of the machine, by I'm guessing the founder, which I found impressive. Impressive in the sense of he's well spoken and seems to have wrestled through all the challenges of design and bringing a complex product to market. No small feat.

I also start thinking what if you welded the frame, stress relieved it, scraped or ground the mounting points for flatness, filled it with epoxy granite for damping etc.... but maybe it makes more sense to use it as and just take light cuts and think of it like 3D printing ..... who cares how long it takes.

 

[1018Machine]

CanCam in TO also had a model like that at one time. Before I bought my laser I was looking at their version of this unit to do my deep engraving and so on. I was very disappointed with their samples. Perhaps I was expecting too much and the stuff I wanted it for was very small like logos and so on but it was very rough! Maybe they didn't know how to run it either!

I hope yours works out well for you, post some video of it running!

 

[DavidR8]

Definitely watching how you get on with it.

 

[Mike R]

Well, 5 of 6 pieces showed up today, but the missing one is my fault for trying to redirect the shipment to a UPS store for pickup. Only 1 piece got redirected while the rest got dropped on my front step with just a doorbell ring according to my wife, no signature required these days I guess.
That's alright though, I need to make room for it in the shop - there are no free flat spaces at the moment (never are...)

 

[Mike R]

That is an interesting machine, I'm looking forward to seeing how it works out.

Part of me wants to pull the trigger, the other part is doubtful about linear bearing quality, run out of collets, spindle quality etc. I also am curious how they create flatness (a linear bearing doesn't create flatness, it will bend to whatever its bolted do).

They are local for me, i wonder if they'd demo it? I found this overview of the machine, by I'm guessing the founder, which I found impressive. Impressive in the sense of he's well spoken and seems to have wrestled through all the challenges of design and bringing a complex product to market. No small feat.

I also start thinking what if you welded the frame, stress relieved it, scraped or ground the mounting points for flatness, filled it with epoxy granite for damping etc.... but maybe it makes more sense to use it as and just take light cuts and think of it like 3D printing ..... who cares how long it takes.

I agree on the rails need a flat reference - to a degree. We'll see how it goes but in this case I think the rails are short enough and stout enough. Regardless I'll be tuning this up as I go and if I need to I can run the structure parts on my surface grinder to get a bit more flatness. Probably won't - I'd like to just build it as designed and see its performance for myself. If further improvements are needed I can go back later (yeah right...like that ever happens....)

 

[Mike R]

Last box was picked up today. Got started on assembly. First issue was no instructions anywhere. Emailed the manufacturer at 4:00, got a response at 6:40 with a google drive link to the pdf instructions and other files.

First impressions:
Seems quite well thought out, and the assembly manual is quite detailed. I've got a fair bit of experience writing instructions, so I tend to nit pick, but so far up to step 10 (about 28 pages in) I've only noted 2 areas that could be improved (one is the text tells you that the render can be ignored and install the bolts from the other side foe ease of tightening later - should be fixed as reading is usually skipped...) , and another place where there should be a helpful note that the bolt doesn't pass through but rather goes to a threaded hole that is blocked (for pushing the plate into alignment). As I said, for me I find that a relatively good score.

Here is where it stands as of now. Not aligned really at this point, its all loose and roughly aligned. There are a lot of fasteners in this thing but it does have a good mass to it.
Reading ahead the next steps are the linear rail installation, and then ballscrew assembly and mounting.

I've been taking video as I go, maybe I'll put together a Youtube video of it eventually (mostly time lapse video as the progress below was made over 2 hours....).

 

[TorontoBuilder]

Last box was picked up today. Got started on assembly. First issue was no instructions anywhere. Emailed the manufacturer at 4:00, got a response at 6:40 with a google drive link to the pdf instructions and other files.

First impressions:
Seems quite well thought out, and the assembly manual is quite detailed. I've got a fair bit of experience writing instructions, so I tend to nit pick, but so far up to step 10 (about 28 pages in) I've only noted 2 areas that could be improved (one is the text tells you that the render can be ignored and install the bolts from the other side foe ease of tightening later - should be fixed as reading is usually skipped...) , and another place where there should be a helpful note that the bolt doesn't pass through but rather goes to a threaded hole that is blocked (for pushing the plate into alignment). As I said, for me I find that a relatively good score.

Here is where it stands as of now. Not aligned really at this point, its all loose and roughly aligned. There are a lot of fasteners in this thing but it does have a good mass to it.
Reading ahead the next steps are the linear rail installation, and then ballscrew assembly and mounting.

I've been taking video as I go, maybe I'll put together a Youtube video of it eventually (mostly time lapse video as the progress below was made over 2 hours....).
View attachment 51926View attachment 51928View attachment 51929

Nice that it can be built quickly