Cheap CNC Milling Machine - It's Arrived!

[flubrush]

I'm curious to see whether I've wasted my money or not!

 

It won't be a complete waste of money if it teaches you what to look out for next time. :-)   The first lathe I got was an old, umpteen hand one and was a bit of a dog.   I never did any good work on it but it taught me what to look out for in the next lathe. :-)

 

I meant to mention that I mostly work with a piece of Conti board as a spoil board on the machine table.   This gives a smooth surface on which to use double sided tape to hold down the styrene sheet.   The Conti board is remarkable true in thickness and flatness and I don't have much problem making it flat and true for milling.   Letraset used to do a double sided lo-tack tape which was low tack on both sides and was excellent for styrene jobs but they seem to have taken it off the market.    The other low tack tapes on the market are low tack on one side only and sometimes it can be difficult getting thin styrene parts off the table without damaging them.   I find a Stanley blade is the best tool around the table for helping to get parts off the table and for scraping adhesive residue off the surface.

 

Also,  you will find that styrene sheet is not a uniform thickness,  sometimes varying by several thou across an A4 sized sheet.  That really threw me when I started milling styrene when I wasn't getting the results I expected.    Now,  I use sheet a size thicker and do an overall surface cut to get it down to the thickness I want which is also a constant thickness.   This can add quite a bit of time to a cutting operation even using a 5mm diameter cutter for the job.

 

Jim.

Edited November 3, 2017 by flubrush

[BG John]

The first stage is to get it built and working. I think it comes with a couple of engraving tools, so I'll probably try making a few pretty patterns first, assuming I overcome, or don't get, the expected hassle with software! I was looking online at DIY pen holders last night, so the next step may be to knock one up, so I can get some practice with drawing out the sort of parts I want to make on paper, before I cut anything. That should give me time to sort out what tools and other bits I need. I want to wait and see what I've got first though, so I don't waste time looking for unsuitable bits. It will be a slow process, but hopefully worth the effort. In the mean time, I've ordered some D-Limonene, so I can laminate thin styrene cut on my Silhouette Portrait, until I'm ready to mill thicker stuff.

[monkeysarefun]

The first stage is to get it built and working. I think it comes with a couple of engraving tools, so I'll probably try making a few pretty patterns first, assuming I overcome, or don't get, the expected hassle with software! I was looking online at DIY pen holders last night, so the next step may be to knock one up, so I can get some practice with drawing out the sort of parts I want to make on paper, before I cut anything. That should give me time to sort out what tools and other bits I need. I want to wait and see what I've got first though, so I don't waste time looking for unsuitable bits. It will be a slow process, but hopefully worth the effort. In the mean time, I've ordered some D-Limonene, so I can laminate thin styrene cut on my Silhouette Portrait, until I'm ready to mill thicker stuff.

 

I bought a similar but slightly larger 3040 Chinese CNC machine.

 

IT does work well, and there are plenty of CNC websites specifically catering for these Chinese machines with tips and upgrade info.

Also youtube has a few videos posted about specific machines - this one for instance looks like a slight variation on the one you have bought?

Edited November 4, 2017 by monkeysarefun

[BG John]

I bought a similar but slightly larger 3040 Chinese CNC machine.

cnc.jpg

 

IT does work well, and there are plenty of CNC websites specifically catering for these Chinese machines with tips and upgrade info.

Also youtube has a few videos posted about specific machines - this one for instance looks like a slight variation on the one you have bought?

Thanks. I think I've already seen that video, but it's useful to watch again. There seem to be two types generally available, possibly with small variations. One has the z axis supported by a larger plastic diagonal, as in the video and the one I've bought, while the other just has tiny aluminium corner brackets. Maybe both are OK for a laser, but I was dubious about the tiny brackets for physical cutting.

 

I'll probably be watching quite a few videos, and searching out web sites.

[BG John]

It's arrived. I ordered it from a German eBay seller on 2nd November, and it arrived via DHL this morning. £204 including delivery. This is what I got, neatly packed in a foam three layer box. It was cunningly labelled on what turned out to be the bottom of the box, so anyone who rushed in and pulled out the foam packing would have ended up with a heap of loose bits, but I had the sense to turn the box over and lift it off the contents!
 

 

 

 
The only other thing in the box was a single A4 sheet written in German. Scanning it into OCR software, and pasting the result into Google Translate came up with what I've added at the end of this post (after a bit of formatting). Not a word about assembly, or how to go about obtaining assembly instructions! Fortunately Google came up with this, that is the right machine, but the smaller 2418 version, rather than my 3018. There are assembly videos on YouTube, but they run through it so fast that I'd rather have something I can read.

 

Now I need to clear some space, and start building.

-----------------------------------------------------------------------
Read before using

• This machine is designed only for surface engraving of plastics, bamboo and wood,
  Non-iron soft metal, so the application with other purposes may damage it;
   
• Before using the device must wear protective goggles to avoid the damage scrapping eruptions;
   
• Do not try to disassemble the machine or control cabinet for reconstruction or fixation,
  otherwise it is not from the warranty;
   
• Please pay attention to the electricity safety than other electrical appliances, using ratified standard
  Tension, and make sure that its electrical grounding is safe;
   
• Do not place the unit in a damp or dusty environment, and do not allow children to come near you
  or touch;
   
• The timely cleaning and regular maintenance can keep the engraving machine in good working condition, and also extend its service life;
   
• This engraving machine is a mechatronic editing tool, so users should grasp it relatively
  Expertise to master this machine when using;
   
• This manual only contains instructions to the application environment and operation requirements of this machine, which does not involve any other professional knowledge involved to refer to
  Tax calculator, software and materials. Please ask for help from your supplier if you have any problems in this regard.
  
  Basic workflow of the engraving machine:
  1: Install "Mach3 control software" on the desktop computer, and setup parameters for the control software in accordance with the requirements of the engraving machine;
  2: Design the content that should be engraved by design software, and output G code or nc, tab files created by Mach3; can be recognized;
  3: Firmly clamping materials must be engraved on the working platform of the engraving machine;
  4: Import engraving code to the control software Mach3, send to the engraving command from machine after passing by the code, and then the engraving machine will start to work.
  
  Requirements for the configuration of the control computer Master:
  1: The desktop computers must have parallel ports; Notebook PC or USB parallel port can not be used normally.
  2: Minimum computer configuration: CPU / 1G, Êpeicliáer, 20G hard disk,
  Motherboard with parallel port, WIN-XP operating system.
  
  Introduction of software and design software to control:
  1: Control Software: Mach3 recommended (EMC2 and KCAM4 can also be applied, and software vendors for more information) to consult;

[BG John]

I started assembling it, following the instructions linked to in my last post, but soon discovered that the base was coming out the wrong size. If you're building a 3018, don't just blindly follow the instructions for a 2418, as there's a difference. Checking the photos on the eBay listing of the one I bought, there are two cross pieces at the back of the base, rather than one. The uprights also have corner brackets on both sides, rather than just one side. I've assembled the frame loosely to start with, to make sure I'm doing it right. I'll carry on assembling like this until I'm sure everything is OK, then tighten it all up. It's looking quite good so far.

 

I think I've got a piece of kitchen worktop I can attach it to, that should increase the rigidity. I've also got something that may be suitable to make a transparent cover. I want to use it indoors, so a cover should keep the dust from flying around.

 

 

 

 

 

[EKR]

Thanks for keeping us updated with your progress.

I’m sure it’s a subject many of us are interested in.

Just not certain of how much use I would make of one.

 

Oh and good luck

[BG John]

Thanks. I bought it mainly because of the very limited thickness that my Silhouette Portrait can cut. I hope I'm at the start of doing a lot of cutting, and being able to avoid doing a lot of laminating of thin plasticard is appealing. I'm hoping I can also cut loco frames from acrylic, as well as various brackets and mountings for point motors etc.. It would also be useful to be able to engrave circuit boards for some of the stuff I'm doing with Arduinos. I keep thinking of even more potential uses! I just hope it's up to the job. I think a laser cutter would be better, but they're too expensive. You can get lasers for these, but I think the cheapest ones are only any good for light engraving.

 

Perhaps I should have kept quiet until I know if it works, but the risk of making a fool of myself if it's a waste of money is offset by the useful help I may get (and have already got) by going public .

[Junctionmad]

I have a Proxxon MF 50 mill fitted with an aftermarket CNC upgrade. Best piece of kit in my workshop and used far more then my lathe. I mill Delrin, brass and aluminium with no issues.

 

The main drawback is the bed size with as standard only 40mm in the Y direction , this can be nearly doubled with a mod.

 

Fusion 360 , which is brilliant and on a par with solid works , mach3 on an old XP machine with parallel port based stepper drivers , 200 steps per mm

 

When I have funds , my next step is a Seig mill

Edited November 9, 2017 by Junctionmad

[Junctionmad]

Thanks. I bought it mainly because of the very limited thickness that my Silhouette Portrait can cut. I hope I'm at the start of doing a lot of cutting, and being able to avoid doing a lot of laminating of thin plasticard is appealing. I'm hoping I can also cut loco frames from acrylic, as well as various brackets and mountings for point motors etc.. It would also be useful to be able to engrave circuit boards for some of the stuff I'm doing with Arduinos. I keep thinking of even more potential uses! I just hope it's up to the job. I think a laser cutter would be better, but they're too expensive. You can get lasers for these, but I think the cheapest ones are only any good for light engraving.

 

Perhaps I should have kept quiet until I know if it works, but the risk of making a fool of myself if it's a waste of money is offset by the useful help I may get (and have already got) by going public .

Milling abs and styrene can be tricky with heat buildup . For some types of ABS , in the summer , I ended up putting the sheets into my freezer for a few hours !! Edited November 9, 2017 by Junctionmad

[BG John]

Milling abs and styrene can be tricky with heat buildup . For some types of ABS , in the summer , I ended up putting the sheets into my freezer for a few hours !!

I appreciate that I want to cut some of the most difficult materials, despite the initial impression that they must be easy to cut. I've read a bit about it so far. I want to take things a step at a time, get the machine working, and get familiar with making it work, so I know what I'm doing before worrying about that!

[tender]

I have a Proxxon MF 50 mill fitted with an aftermarket CNC upgrade. Best piece of kit in my workshop and used far more then my lathe. I mill Delrin, brass and aluminium with no issues.

The main drawback is the bed size with as standard only 40mm in the Y direction , this can be nearly doubled with a mod.

Fusion 360 , which is brilliant and on a par with solid works , mach3 on an old XP machine with parallel port based stepper drivers , 200 steps per mm

When I have funds , my next step is a Seig mill

Junctionmad.

I also converted my MF50 mill a few years ago but haven't used it for some time. It's driven from an Arduino UNO with a couple of stepper driver (Adafruit I think) and If I remember correctly it requires simple G-code commands to operate.

I've also started using Fusion 360 this summer to do some laser cutting at the local tech.

 

Can you give us a brief explaination as to how you get from Fusion 360 to driving the MF50?

 

Also do you have the mod details to increase the Y direction?

Edited November 9, 2017 by tender

[BG John]

Is there a benefit to using 3D software? My machine is described as 2.5D I think. Effectively 2D, but you can also control the cutting depth.

[Enterprisingwestern]

 

Read before using

• This machine is designed only for surface engraving of plastics, bamboo and wood,

  Non-iron soft metal, so the application with other purposes may damage it;

 

 

Are you confident it's up the task you require of it?

 

Mike.

[BG John]

Are you confident it's up the task you require of it?

 

Mike.

No! But I'll soon find out .

 

I've read enough, and watched enough videos, to be pretty sure it will do the job. That's about the most limiting comment I've seen on them. They are certainly advertised as being for milling. The maximum cutting depth is supposed to be around 30mm, but I'd be pretty happy with 3 or 4mm, although more would be nice. Would anyone have believed a few years ago, that the Silhouette cutters could do what people are using them for? They are pretty weedy in comparison.

 

I've almost finished assembling the mechanical parts, and it seems a pretty solid machine. My only slight concern is that the X-axis bearing shafts flex a bit. That may be a downside with the bigger machine, as they are quite a bit longer. It may be better when I've got the screw fitted.

[monkeysarefun]

 

I think I've got a piece of kitchen worktop I can attach it to, that should increase the rigidity. I've also got something that may be suitable to make a transparent cover. I want to use it indoors, so a cover should keep the dust from flying around.

 

 

 

Cutting plastic I've found the dust tends to stick statically to the cutter, work piece and  surrounds rather than floating around the room!  Another thing to bear in mind is that depending on what you are cutting, the cutting action can be incredibly loud. They might be little machines but they come with a full size soundtrack.

 

Also, apologies if you know this already but CNCzone has a forum dedicated to Chinese machines which I've found very helpful:

 

http://www.cnczone.com/forums/chinese-machines/

[BG John]

Almost everything is assembled. The instructions for the 2418 I linked to earlier seemed to fade away a bit as the build went on, but by that time there weren't many bits left, and it was obvious where they went! I've got it all fairly well aligned, but nothing is fully tightened up yet. I wanted to make sure it all went together first. I had to use a bit of intelligence (fortunately not a lot was needed!) to decide on the spacing of the rails on the Y-axis, as the table is wider than the 2418.

 

I haven't fitted the end bearing bracket on the X-axis yet (the bit hanging off the long screw at the top), for a reason I'll mention in a minute.

 

 

 

The uprights are pretty well supported, with two corner brackets, and a 3D printed diagonal:

 

Two things to watch out for. The nuts that hold everything to the frame are the sort that drop into the aluminium channel, then need to be turned at 90 degrees (like the ones used in aluminium greenhouses). They're a bit fiddly to get in position, and a few of them turned as I screwed them up. I need to check each one, and redo a few. If you build one it's something to watch out for. There seem to be plenty of spares of these and the matching screws, if the carpet monster grabs some!

 

The one thing that I need to resolve, is fitting the two leadscrews into the end bearings. They run in ball bearings inserted in 3D printed brackets, and are a tight fit. The lower (Y-axis) one needs to be pushed through a bit further, and the upper (X-axis) one needs to go through quite a long way. They need some persuasion without bending the shaft or damaging the bearing, and I'm not sure how to do it yet.

 

[BG John]

I got a bit distracted, and haven't done any more on this, except doing a bit more to support the Chinese economy! The reason it only takes ⅛" tools is that it comes with the brass adaptor in the photo, that fits on the 5mm motor shaft. I found this neat little chuck on AliExpress, that arrived today, and the adaptor with it (the black bit) is a nice fit on the motor. So it looks as though I'll be able to use any size tools.

 

I bought a few different types of tool on AliExpress as well, and so far these 3mm and 0.8mm ones on ⅛" shafts have arrived. There are some drill bits, and 1.2mm mills on a different sized shaft on the way too. So when I get back to it I should have plenty to try/break!

 

Meanwhile, back to getting my head round 3D CAD, G-code converters, and stuff!

 

[Junctionmad]

Junctionmad.

I also converted my MF50 mill a few years ago but haven't used it for some time. It's driven from an Arduino UNO with a couple of stepper driver (Adafruit I think) and If I remember correctly it requires simple G-code commands to operate.

I've also started using Fusion 360 this summer to do some laser cutting at the local tech.

 

Can you give us a brief explaination as to how you get from Fusion 360 to driving the MF50?

 

Also do you have the mod details to increase the Y direction?

Fusion 360 comes with a CAM module , and in that mode you can select a G code processor for your mill I used the Mach 3 profile.

 

Fusion cam then generates tool paths etc. I'd say it took me 3-5 hours to get the first job done learning as I went

 

I use plastic for all my trial jobs ,

 

The mod to the y axis is detailed on the web somewhere it involves moding the end plate to allow the carriage to traverse over the end plate giving more Y movement at the cost of a slightly less supported carriage when it's in the extended position.

Edited November 24, 2017 by Junctionmad

[brianCAD]

snip. . . . The reason it only takes ⅛" tools is that it comes with the brass adaptor in the photo, that fits on the 5mm motor shaft. I found this neat little chuck on AliExpress, that arrived today, and the adaptor with it (the black bit) is a nice fit on the motor. So it looks as though I'll be able to use any size tools.

 

 

I'd be very wary of using that chuck.  Check to see if it runs true and is not out-of-balance at full motor revs.  Check to see if cutters run true when gripped in the chuck.  By now the business end of the cutter is a long way below the support of the motor/spindle bearings and the whole unit might vibrate horribly when attempting to cut anything no matter how soft.

 

Suggest seeking out a skilled lathe operator who can make short 'adaptors' to mount cutters of assorted diameters directly to the motor shaft - similar to that supplied for 1/8" dia tools.

 

I've only just come across this thread, and would have preferred at the outset that you made some use of your TH pantograph machine first, to gain machining experience helpful for evaluating CNC possibilities.  A lingering concern is that while 'CNC' control systems are well sorted and robust today, the same can't be said for some inexpensive hobby machines leveraging off the technology.

 

-Brian M 

[BG John]

For what the chuck cost, I am wary. I'll find another use for it if it's no good. I'm aware that getting everything running true on these cheap machines is one of the challenges.

 

It's a nice idea to get the TH going, but I may spend time on it, and more time getting proficient in using it, then my life changes and it has to go. If I've still got it in a year or two, after I may have had to make some big decisions, and take some drastic action, maybe it will be worth the effort. But at the moment, I need tools that can help me get some modelling done, that don't take up a lot of space, and can be used in the house (and especially upstairs on a fairly weak floor).

[rdr]

mycncuk is a useful forum for routing.

[raymw]

There is plenty of 1/8th inch tooling, and your machine is unlikely to be able to handle anything bigger, at least not to start with. Get some ground silver steel  rod, and make your own D bits- no need to harden/temper for many materials you are cutting. A few things you need to get - A good fine diamond sharpener, for keeping an edge on the tools, but first of all, cover that pretty ali table with, say, half inch quality ply (or  soft plastic (alkathene?) chopping board) - it will save you tears when your first jobs go wrong, and you machine grooves into the machine. Experiment with double sided tape for holding flat sheets, - not all tapes are equal. You can clamp more rigid material,by using wood screws into the plly and thin ply washers, and make sure your g-code misses whatever you are using for clamps. A few short lengths of one inch ali/light steel angle will be useful for jury rigging clamps, vice substitutes, for holding more solid material until you decide to do something else

 

The first job you need to run, once the spoiler board is fitted, is to cut out a circular hole, about 2 inches in diameter, and a close fitting circular plug in a piece of mdf/acrylic, 3mm thick/whatever . Hold up to light and rotate plug, see if it and hole are truly circular. If not then sort out the machine backlash. Then mill a square square pocket and square plug. The square should fit in whatever way it is placed into the pocket. That'll check for perpendicular x/y axis. You can write the g-code for both without flaffing around with cad/cam.

[BG John]

Thanks Ray. I wasn't thinking of using bigger tools, but just having the option to use different sizes, especially as some of the early comments on this topic suggested that only being able to use ⅛" cutters was limiting.

 

I've got a soft plastic chopping board that is well past the time when I should have replaced it in the kitchen! If I hadn't bought a replacement already, I could have engraved some pretty patterns in a piece of home grown sycamore. In fact, I could go into the chopping board manufacturing business with the number of trees I have!

 

I think the first step will be to use a pen/pencil, until I'm brave/confident enough to know I won't be gouging lumps out of the wrong places! As we discussed in another topic, on 3D printed pen holders, now I've decided to have a 3D printer as well, I could adapt someone else's design to suit my machine, and the pens I have, and use it as a practice item for printing. Or I can put a pencil lead in the chuck, as you also suggested. Much easier than bodging up something to fit the ⅛" coupler.

 

Cutting test circles and squares is a good idea. I'm currently going through the hassle of non/late delivery of a dial gauge bought on eBay, that I want to test the accuracy of the moving parts. It's definitely needed for the 3D printer, as the one I'm building is known to have problems with a wonky z-axis, but I don't know how accurate the mill is. It's got anti-backlash thingies, but it's also cheap and Chinese .

 

I haven't forgotten I need to learn to write G-code. It's on the to-do list, after getting my head round all the software I need.

[BG John]

mycncuk is a useful forum for routing.

Thanks. I don't think I'd come across that one. I'll have a good look later.