First Thread? Making a Mini CNC Milling Machine

[Jack Sparrow]

here is a picture showing the control box, the Nema 17 stepper,the bracket holding the motor, the coupling between the motor and the drive shaft, and the power supply.
I have two other steppers and the appropriate hardware.
The box looks nice, but it's an old card, has a firmware that I am not familiar with, and not easy to connect.

 

[johnv]

Finished the 3D printing of the structural parts, then a few hours removing supports, inserting nuts and cap screws, and sitting them together to get an impression of the size and shape. Some of those rods are not hardened steel. Just sitting there for the photo.
Next I will use my "big" CNC mill to make the aluminium plates which form the bases for the 3 axis slides. That could be done manually on a drill press, but in my hands the CNC machine is more accurate.
Meanwhile waiting for various hardware bearings, trapezoidal screws and nuts, etc to arrive by post from OS.
And in the photos below is one of the electronics box which contains the breakout board, drivers for the stepper motor, connections, power supplies. This one was made by Stuart, and I intend to just copy it.
Sorry about the picture rotation issue. I can't seem to fix it.

 

[Jack Sparrow]

Finished the 3D printing of the structural parts, then a few hours removing supports, inserting nuts and cap screws, and sitting them together to get an impression of the size and shape. Some of those rods are not hardened steel. Just sitting there for the photo.
Next I will use my "big" CNC mill to make the aluminium plates which form the bases for the 3 axis slides. That could be done manually on a drill press, but in my hands the CNC machine is more accurate.
Meanwhile waiting for various hardware bearings, trapezoidal screws and nuts, etc to arrive by post from OS.
And in the photos below is one of the electronics box which contains the breakout board, drivers for the stepper motor, connections, power supplies. This one was made by Stuart, and I intend to just copy it.

View attachment 477137

View attachment 477138

View attachment 477139

Looks very neat and tidy. Well done and congratulations. I can`t remember if you mentioned it in a previous post but what firmware were you going to use? GRBL? ALso, and i am just curious. but what size steppers were you going to use? Mine are all Nema 17

 

[johnv]

Looks very neat and tidy. Well done and congratulations. I can`t remember if you mentioned it in a previous post but what firmware were you going to use? GRBL? ALso, and i am just curious. but what size steppers were you going to use? Mine are all Nema 17

Thanks for the feedback Jack Sparrow.
Firmware..... Mach 3 to operate the mini mill. I use Vectric V Carve Pro for my CNC milling designs to generate the G codes. I don't recognize GRBL. And the steppers will all be Nema 17. Nema 17 should be adequate for cutters up to 3.175mm dia.

 

[Jack Sparrow]

Thanks for the feedback Jack Sparrow.
Firmware..... Mach 3 to operate the mini mill. I use Vectric V Carve Pro for my CNC milling designs to generate the G codes. I don't recognize GRBL. And the steppers will all be Nema 17. Nema 17 should be adequate for cutters up to 3.175mm dia.

Oh yes Mach 3. I have heard of that. I like Vectric V Carve as well. Easy to use and very powerful. I know their flagship product is Aspire, but it is so expensive.
GRBL is freeware. I also use freecad for the cad design which is freeware as well. I might upgrade to Vectric V carve one day. I tested it out and it is really handy to use and much easier than freecad.
I have just started to learn these software.

 

[Jack Sparrow]

I am currently working on the MSW Constitution and there are some parts which are really really thin. I want to try and replace them using the MF70 and the CNC hardware attached. That is my objective right now.

Similarly I have a POF Enterprize that I want to build and again there are some very delicate parts that I would like to make more robust.

or I might 3D print them. Have not decided yet. Whichever is more fun to do. That is my main motivation, really.

 

[johnv]

Yes, my Constitution is an old Mamoli kit. In retrospect I regret not getting the MSW version. But I spotted the mamoli on Ebay, and made a sudden decision to try a ship building kit. Now I am hooked.

 

[Jack Sparrow]

Yes, my Constitution is an old Mamoli kit. In retrospect I regret not getting the MSW version. But I spotted the mamoli on Ebay, and made a sudden decision to try a ship building kit. Now I am hooked.

It is quite addictive and I really enjoy the hobby especially since I am a tool nut.

 

[SAHaskell]

Not sure if this is the correct forum to post about making a machine. But I will see what responses I get, whether I continue with posting the build or not.
I am a newbie as far as model ship building goes, but I do have experience in CNC and conventional metalworking, making working model steam engines, model cannons, making wooden furniture, casting metals, 3d printing, etc etc. I recently decided to make a small CNC milling machine, and wondered whether any SOS readers would be interested in in watching progress. Let me know. Some early progress photos are attached, including the machine which I am copying.View attachment 476504

I am vary interested in your project, I'm not sure about building one myself, but the learning experience is very appealing.
Happy Modeling
Steven Haskell

 

[mleonc]

Excellent, congratulations on the work.

 

[johnv]

Some more time in the workshop today, making the X table, Y backplate, Z backplate and the base for the mini CNC mill. Although I used my large CNC mill for this, it could have been done on a decent drill press.
The base was cut from 16mm aluminium bar, and the X,Y and Z plates from 6mm aluminium bar.
The first photo shows milling the 6mm X plate to size on my big mill. The heavy bars are to keep the workpiece straight. The second photo is the big mill. I could say that it is unusually messy, but that would not be true. On the left you can see my CNC rotary table, which is not being used for this project. The third is CNC drilling the Y plate. The fourth is using my shop made tapping head. A the fifth is the finished base plate and the X and Y plates.
I still have to finish the Z backing plate. And to drill and tap some holes into the end of the 388mm long X plate... In order to accomplish that, accurately. I will use a large right angle plate bolted onto the bed of the milling machine, with the workpiece cramped vertically.
You might notice a lot of swarf on the floor. I have had highly venomous tiger snakes in my workshop on 2 occasions, and both episodes occurred after I had swept the floor. SO these days I always leave lots of sharp swarf on the floor to make them feel unwelcome. Since adopting that policy I have had no more unwelcome visitors of the no legs variety.

 

[Jimsky]

Obsolutely love your work, more please! I am a big fan of small machinery, not necessarily CNC, though.

 

[johnv]

CNC Mini Mill. The Costs.
An invariable aspect of making models, tools and machines is that I ALWAYS underestimate the time that the project will take, and how much it will cost. It is just as well, because SWMBO might not give the tick of approval if I was more accurate with my estimates.
For the CNC Mini Mill, I think that I estimated $AUD 500-600 and maybe a month or so to build it.
Well, perhaps foolishly, I added up the costs so far. The 3d printing filament was about $AUD30. The hardened steel rods, bearings, trapezoidal screws and nuts, and Nema 17 motors about $AUD 200. Still waiting for most of those parts. Nuts and bolts, mostly M3 stainless, out of my workshop stock, so maybe $AUD30-50.
In the past day or two I have ordered the electronics. Well, that blew the estimate out of the water. I will post a list later, but it came to about $AUD1000. It is a few years since I have purchased CNC parts. Mostly from China, some from USA. The Chinese components were inexpensive, and I ordered more than I needed so I have replacements on hand. Postage is the killer when buying from USA.
The first photo is the printed components, the machined aluminium plates, all just sitting there. And the second is a box of Nema 17 stepper motors.

 

[Steef66]

Don't forget the time on searching Aliexpress for these parts, best price and right part. Sometimes I was searching for a few parts and it took me several hours to succeed.

 

[johnv]

I have paused this Mini CNC Mill project while waiting for parts to arrive by post.

 

[johnv]

I have paused this Mini CNC Mill project while waiting for parts to arrive by post.

Some parts arrived by post in the last couple of days. The hardened steel rods unfortunately were bent, so I used some from my workshop. Not only bent but also 1-2 thou undersized.
So here is pic of the build. The stepper motors are attached, as are the linear bearings, rods, and some other bearings. The mill is starting to take shape.
I have the 8mm trapezoid screws, and the anti backlash spring nuts loaded nuts, and they will be cut to size and attached next.

 

[johnv]

Some more stuff has arrived, and I spent most of today cutting and fitting the trapezoidal screws, and spring loaded anti backlash nuts. It required disassembling most of the machine, and some fiddly reassembly.
Some of the electronic CNC stuff has also been arriving from China, and locally. Not really started on the electronics yet.
The spindle is a Proxxon LBS/E, which provides a spindle speed variable from 5000 to 20000, which should be adequate for most tiny drills, and also cope with small milling cutters up to 3.175mm diameter. And it has a good set of small collets. And the long 20mm diameter snout makes it easy to hold in the printed holder. Much better than a Dremel.

 

[Steef66]

Looking to this machine yes it's great to make this, the time you put in it, is a great time, like building a ship. But the price of the parts will be to my guess over the 200 euro. Was a Proxxon MF70 not cheaper? Just a question. What is the advance of this machine?

 

[Jack Sparrow]

Looking to this machine yes it's great to make this, the time you put in it, is a great time, like building a ship. But the price of the parts will be to my guess over the 200 euro. Was a Proxxon MF70 not cheaper? Just a question. What is the advance of this machine?

Well I have a MF70 with a CNC kit and it cost me about 500 CAD$

 

[Steef66]

conversion kit on Ali express with Alu stepper motor brackets just around the 100 max 140