Cheap CNC Milling Machine - It's Arrived!

[BG John]

Edited on 8/11/17:

I've now bought one. Arrival and assembly starts at post No 30.

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There doesn't seem to have been any recent discussion on CNC milling machines, and I wondered what the cheap ones currently available are like. I'm wondering if one would be a good companion to my Silhouette Portrait, for cutting thicker materials. I can't spend the money on a decent laser cutter, and don't fancy the optional laser units for these cheap machines. I've got a Taylor Hobson Pantograph Engraver, that I've never set up and used, but it's a workshop machine for a solid floor, and would go through the floor of my railway room, if it didn't do me a serious injury getting it there! Selling it should pay for a cheap CNC miller/engraver, that although nowhere near the same quality, may well suit me better.

 

This is the sort of thing I'm thinking of, from a quick search. I imagine there could be another £50 for VAT and stuff on top of the price.

 

An alternative is to build one myself, as all the parts can be readily bought, and there are no end of instructions on how to do it on the web, but it would be a bigger job. Maybe buying a complete kit is a better way to start, and I could modify or upgrade parts of it over time if I wanted to. I'd almost certainly go for an Arduino driven one, as I play around with them already.

 

Has anyone got any comments or suggestions?

Edited November 8, 2017 by BG John

[AndyH]

Hello John,

It is an engraver, very light milling.

It depends what you want to make, and out of what material? Non-ferrous? Milling resin board?

 

I’d get the Taylor Hobson working as that is fantastic quality and will allow you to make most things. If Tony Reynalds uses one, that is good enough for me. Make larger patterns and scale down. Almost as fast as programming toolpaths.

Andy

[BG John]

Thanks Andy. I'm not sure that the Taylor Hobson is a practical option, due to the weight and size. I really need something that can be used in my modelling area, rather than the workshop. Maybe I shouldn't have mentioned it at all, although if anyone is interested in buying it.... .

 

I'm more interested in comments on the CNC machines, to see if one would be worth buying. Its main use would be for building 4mm and 7mm scale locos and rolling stock, as it will cut thicker material than a Silhouette. The obvious down side is that it won't cut square internal corners. I'd be using wood or plastics. It's a shame they don't have the power to cut hard metal, but I don't think that's a major problem.

 

From a bit more reading and video watching last night, they mostly seem pretty good, and appear to have 0.1mm accuracy. If I could afford it, I'd buy something like a Darkly Labs Emblazer, so I see this as something more affordable between a Silhouette and a laser. You can get lasers for these machines, but they're very low power, and I'd be very dubious about it anyway, so I'm not considering that.

[alastairq]

Hi..you may be aware of this.....as it has been threaded on here before, but just a reminder

 

Proxxon pantograph used as a milling machine?

 

 

Seems it helps to also have a laser cutter as well, for the manufacture of templates?

[BG John]

I was just thinking of them while having my lunch! The Proxxon is certainly a more manageable size than the TH, and a similar price to the CNC machines. Probably better quality too. But it's only got a small working area, and I'm thinking of using it for cutting out objects up to O gauge coach sides, and possibly buildings. I'd thought of using my Silhouette to cut templates, but I don't know if they'd be thick enough without laminating. Giles uses his Proxxon to cut metal, which would be a big advantage. I have things planned that have fiendish valve gear that I'll never be able to cut out by hand! However, I was watching a video last night of someone who had replaced the weedy cutting motor in a CNC machine with a flexible drive connected to a big Dremel. He didn't show it cutting metal, but I think he suggested it was possible.

 

It's all about getting the best compromise. If I gave up food for a few years, I suppose I could buy a variety of £1,000+ machine tools to do everything I could dream of, but may not be in a fit state to use them!

[flubrush]

Just one or two things about the machine.    I can't see any mention of control software for it.  The control board has a USB connection but I can't see any mention in the listing about what drives the machine.   It could be worth finding out before you splash out any money.     Some of these Far Eastern milling machines come with bootleg copies of control software like Mach3.    But if the controller is based on GRBL then there is free CNC software which will control it but you will need CAM software to generate the GCode files to use with the control software.

 

The collet on the spindle is 1/8" which suits a lot of engraving cutters.    But if you want to do proper machining you will want to use carbide slotting cutters and you could find that you have to use ones with metric shanks,  which could be a problem with the 1'8" bore.   It would be worth investigating what's available with 1/8" shanks.  For cutting plastic you need carbide cutters - high speed steel cutters tend to heat up and melt the plastic giving a poor finish.

 

But it could be worth a punt for cutting plastics and wood.  In fact you don't want too much power in a milling machine when cutting plastics like styrene since the material itself starts to deform around the tool and give poor results if you start pushing too hard in feed speeds and cutting depths.

 

Jim.

[nick_bastable]

I have a Proxxon and it is a lovely bit of kit for 2mm  and probably 4mm however if you can try for the Emblazer which is a great bit of kit although I expect for 7mm you may need the A3 version

but they have their limitations 

 

Nick

 

who is lucky enough to own both  

[BG John]

Just one or two things about the machine.    I can't see any mention of control software for it.  The control board has a USB connection but I can't see any mention in the listing about what drives the machine.   It could be worth finding out before you splash out any money.     Some of these Far Eastern milling machines come with bootleg copies of control software like Mach3.    But if the controller is based on GRBL then there is free CNC software which will control it but you will need CAM software to generate the GCode files to use with the control software.

 

The collet on the spindle is 1/8" which suits a lot of engraving cutters.    But if you want to do proper machining you will want to use carbide slotting cutters and you could find that you have to use ones with metric shanks,  which could be a problem with the 1'8" bore.   It would be worth investigating what's available with 1/8" shanks.  For cutting plastic you need carbide cutters - high speed steel cutters tend to heat up and melt the plastic giving a poor finish.

 

But it could be worth a punt for cutting plastics and wood.  In fact you don't want too much power in a milling machine when cutting plastics like styrene since the material itself starts to deform around the tool and give poor results if you start pushing too hard in feed speeds and cutting depths.

 

Jim.

Thanks Jim. After a bit more research, I've found this one, that ships from Germany and should avoid VAT and other import charges. I've found some quite good reviews of it, and a few bad of course. It seems to be available from a number of suppliers, and under a few brand names. It's also on Amazon at a higher price. There are three bed sizes, 160mm x 100mm, 240mm x 180mm and 300mm x 180mm. The small one is £20 cheaper, and the middle one £5 cheaper, so I think the biggest one makes sense. It's still quite small.

 

It uses GRBL and has an apparently not very well known board, although there's a useful discussion on it here. A more common Arduino shield, including an Uno or a Nano is only about £12, if it turns out to be rubbish.

I'm not sure about software, although the reviews suggest that it's dodgy, but that doesn't mean it won't do the job. I currently use Inkscape, and would like to carry on with it, but will change to something else open source, as long as there's a Linux version and I can still produce files for my Silhouette Portrait from it. The Gcode extension looks a bit mind boggling, but I'll get used to it! What other software do I need?

 

I suspect the power supply is a bit dodgy too, so may need to replace that.

 

There seem to be ⅛" cutters available, and there are various ones from China on eBay. I would like to be able to cut styrene. My thinking is that I cut the big stuff on this, and do the fine detail on the Silhouette. As it won't cut metal, I suppose acrylic would be OK for things that need to be rigid, like loco frames. This needs to be a useful tool, but it's also for learning on, so once I've built and got it working, I should be able to knock up a small and more powerful one for cutting metal. I only really need it for small items like loco motion.

[BG John]

I have a Proxxon and it is a lovely bit of kit for 2mm  and probably 4mm however if you can try for the Emblazer which is a great bit of kit although I expect for 7mm you may need the A3 version

but they have their limitations 

 

Nick

 

who is lucky enough to own both  

No chance of an Emblazer I'm afraid, although I follow the topic with interest!

[flubrush]

Thanks Jim. After a bit more research, I've found this one, that ships from Germany and should avoid VAT and other import charges. I've found some quite good reviews of it, and a few bad of course. It seems to be available from a number of suppliers, and under a few brand names. It's also on Amazon at a higher price. There are three bed sizes, 160mm x 100mm, 240mm x 180mm and 300mm x 180mm. The small one is £20 cheaper, and the middle one £5 cheaper, so I think the biggest one makes sense. It's still quite small.

 

It uses GRBL and has an apparently not very well known board, although there's a useful discussion on it here. A more common Arduino shield, including an Uno or a Nano is only about £12, if it turns out to be rubbish.

 

That might be worth a go.  You seem to have managed to dig up a few discussions on the machine,  GRBL, etc.,  so you will probably be able to get someone to help you out if you run into problems..  The Emblaser1 also uses GRBL and that seems to work well.

 

With GRBL you can get software like Universal GCode Sender to interface with the GRBL board to send GCode files to the machine.   To generate the GCode files,  you need a CAM program (or a program like Fusion 350 which has a CAM facility built in).  I use Vectric Cut2D which is very good but I suspect that its current price could be more than your machine's price.    I got it bundled with my CNC mill so I didn't have to fork out separately.   Programs like Vectric Cut2D have quite good drafting facilities,  but I prefer to do my drawing in AutoCAD LT or Draftsight and import the files into Cut2D to geberate the GCode Files.   Cut2D will import files from Autocad and various other vector graphics programs,  but not Inkscape.

 

http://support.vectric.com/aspire-questions/item/what-vector-file-formats-can-be-imported

 

So if you are looking for a CAM program,  even a free one,  you might want to look at what files it will import.

 

The process is a bit long winded - draw in your vector graphics or CAD program,  export a file to your CAM program to generate the GCode files,  generate a text GCode file from the CAM program to use with the program which interfaces with the GRBL board on your machine.   You might well find setups which streamline the operation.  With Emblaser1,  Vectric's Cut2D Laser can interface directly with the GRBL board so that CAM files are sent directly to the board in the machine and the CAD design can be done in Cut2D laser as well.

 

On buying a milling machine of any type,  get the biggest you can afford or accommodate.   Not only do you have to take account of the maximum travels of the table,  you also have to allow for clamping material on the table and that also requires a bit of space..   However you will find that CNC milling is not a fast process and if you draw up a large complex part to machine you could find it taking hours (I have read of some process taking over a day!!).  I now find myself breaking jobs down into sub sections which only(!!??) take a few hours so that if any part has to be re-done for any reason,  it's only a matter of hours,  not days. :-) , and that can just about justify a smaller table. :-)

 

Jim.

Edited October 25, 2017 by flubrush

[BG John]

Thanks Jim. It's obviously more involved than using the Silhouette, but hopefully is worthwhile if it will handle thicker materials. If I buy one, I suppose the first step is to see what software comes with it, as I need to know the machine works. Then decide what needs changing from there.

 

I think the 300x180 should be big enough. My plans mainly involve small locos and 4-wheel rolling stock in O and O-16.5, so there should be plenty of room. I'd like to see how it handles scribing brick and stonework on buildings. Speed isn't necessarily a problem, although I'm not sure I'll be cutting many complex shapes. It might encourage me to use a good old fashioned knife and steel rule sometimes though!

 

If I'm going to achieve what I've got planned at the moment, I need to decide pretty soon if I'm going to buy one, as I will have a lot of designing and cutting to do over the next year or so. It's needs some thinking about first though. I'm learning to break jobs down into small pieces, and my thinking at the moment is that I do the easiest bits of a number of models to start with, then gradually work up to the complicated bits. So I'll be making components for models I won't be assembling straight away.

[Happy Hippo]

Most of the CNC mailing machines you see advertised at low prices on eBay are no more than engraving machines.

 

They are made out of aluminium and perspex so don't have the structural strength to carry out serious milling operations.

 

Look at the hobby machines available at ArcEuroTrade, but take a deep breath before looking at the prices.

 

If you have the time and the inclination, get a manual mill and convert it yourself.

 

Cheap tools are a false economy which is why the Emblaser laserds are so much more expensive than more powerful CO2 models from China.

 

That is not to say good results cannot be achieved with such, but it is a much more rocky ride.

[monkeysarefun]

I bought a Chinese 3040 machine off of Ebay a few months ago. It is probably a little larger than what you are after, but looking at the first one you linked - which looks to have come out of the same Chinese factory - a couple of things I found might apply to that one too.

 

Firstly, check the connectivity - some suppliers use a controller that has a USB connection to your PC, others require a parallel port.

 

Secondly, the CNC controller software. Again, some supply a 'dodgy' unlicensed  version of Mach3, others supply a license for PlanetCNC's USBCNC software

 

AS to router bits, if you are cutting plastic make sure you get Carbide ones - the other ones will melt it. Or is it the other way around? I always forget!

Edited October 25, 2017 by monkeysarefun

[BG John]

Most of the CNC mailing machines you see advertised at low prices on eBay are no more than engraving machines.

 

They are made out of aluminium and perspex so don't have the structural strength to carry out serious milling operations.

 

Look at the hobby machines available at ArcEuroTrade, but take a deep breath before looking at the prices.

 

If you have the time and the inclination, get a manual mill and convert it yourself.

 

Cheap tools are a false economy which is why the Emblaser laserds are so much more expensive than more powerful CO2 models from China.

 

That is not to say good results cannot be achieved with such, but it is a much more rocky ride.

I don't want one that sends letters . Sorry, I couldn't resist .

I'm considering it to give deeper cuts than a Silhouette Portrait, so it's only for light work. I want to do milling, rather than engraving, but only on plastics of a few millimetres maximum. My Taylor Hobson is "no more than an engraving machine" too, although rather more solid!

 

If I wanted to do serious milling, I'd buy a milling machine, but like the TH, it would go through the floor, if I could even get it upstairs to my railway room! It's not really about economy (false or otherwise), but a choice between a cheap one or none at all. I've no idea where my life is going at the moment, and the TH may have to go even if I do start using it. If I was definitely able to keep it, I've thought of adapting it to do light milling without using the pantograph.

[BG John]

I bought a Chinese 3040 machine off of Ebay a few months ago. It is probably a little larger than what you are after, but looking at the first one you linked - which looks to have come out of the same Chinese factory - a couple of things I found might apply to that one too.

 

Firstly, check the connectivity - some suppliers use a controller that has a USB connection to your PC, others require a parallel port.

 

Secondly, the CNC controller software. Again, some supply a 'dodgy' unlicensed  version of Mach3, others supply a license for PlanetCNC's USBCNC software

 

AS to router bits, if you are cutting plastic make sure you get Carbide ones - the other ones will melt it. Or is it the other way around? I always forget!

I want one that's compatible with Arduinos, as I play with those anyway, so that's something I'm looking for.

 

If I buy one, I'll see what software comes with it, then look around for something open source. Ideally I need Linux and Windows versions.

 

Flubrush said carbide earlier, so I hope you're both right!

[flubrush]

Flubrush said carbide earlier, so I hope you're both right!

 

Definitely carbide. :-)

 

Jim.

[rdr]

whichever machine you go for use a current mach3 and ditch the original chinese supplied one (keeping the xml file). Download the current version from Artsofts website. and you can run the machine up to 500 lines without the license but it only costs just over £100 and it's well worth it.

 

Good machines are Denford Starmill, Novamill, Triac, and are all single phase desktop size. These are real mills and cut any materials really accurately, and convert to mach3 easily.

 

They come up on ebay fairly often and range from £500 - £2000, and are really good value.

Edited October 26, 2017 by rdr

[BG John]

whichever machine you go for use a current mach3 and ditch the original chinese supplied one (keeping the xml file). Download the current version from Artsofts website. and you can run the machine up to 500 lines without the license but it only costs just over £100 and it's well worth it.

 

Good machines are Denford Starmill, Novamill, Triac, and are all single phase desktop size. These are real mills and cut any materials really accurately, and convert to mach3 easily.

 

They come up on ebay fairly often and range from £500 - £2000, and are really good value.

$175 is currently about 33% over £100! If it comes with Mach3, I'll try the current free version. It's a shame it's Windows only, as although I'll probably be running the machine from my Windows 7 laptop, my main machine runs Linux, and I'm trying to avoid acquiring more Windows software.

 

Given the ability to spend what I'd like to, I know there are much better options, but as I said earlier, it's a cheap machine or nothing. Due to being a bit younger than the retirees on here who think nothing of spending many hundreds or thousands on their hobby, and a bit of expensive misfortune in recent years, money I spend now potential means no money to pay essential bills at some time in the future. If that changes, I'll have useful experience for helping to buy something better when I know I can afford it. Or it's an incentive to build one myself that does exactly what I want.

[rdr]

maybe the dollar to pound conversion was a lot better when i bought mine, or it was a bit cheaper, i'm not sure.  But it's still amazing value for a great bit of software with fantastic online backup.

 

PS. I'm sure i've run mine on Win 7.

[JohnGi]

Hi,

 

I have a second hand Roland MDX-15. So far I have only used it for cutting/engraving plastics and foam for

buildings. I intend using it for rolling stock in the future. It can (apparently) cut aluminium, brass and NS

if you go very slowly, but I notice that Roland don't advertise their more recent machines as having that

capability- perhaps they realised they were on the limits of what was practical with the machine.

 

I have experimented with ABS, polystyrene sheet, acrylic sheet, foamex/palight, foam board (expanded

polystyrene  core, and Kapa brand foam board (PU core).

 

With cutting plastics the main problem is heat. The chips heat up and then reattach themselves leaving

you with a nasty burr and also a buildup of plastic around the cutter. If you are engraving or milling a 

pocket the melting/remelting can also leave an unsatisfactory finish at the bottom.

 

The cheap Chinese carbide cutters with 1/8 inch shanks are really intended for milling circuit boards. I

feel they're not all that sharp and they create a lot of heat.

 

I get my best results by using Clarke FC3 throwaway cutters (about £5 each, and nice and sharp) to remove

the majority of the material. These give a nice finish at the bottom of the pocket. Then use a small FC3 to 

remove the last 0.1 mm from the edge, and finally a Chinese 0.5 mm carbide to go into the corners. I have

a non Chinese 0.5 mm cutter (much more expensive, but hopefully sharper) but so far i haven't needed to risk it-

its really easy to break the small cutters, even on plastic.

 

The FC3 cutters have 6mm shanks and fit the machine perfectly. The machine came to me with a shop made 

adaptor for 1/8 inch shank tools, but I found this had excessive run out, and tended to overcut into the corners 

of pockets (when using the tool path I just described). I was able to make a replacement for this. I also found that

the machine had excessive backlash on the x-axis which could sometimes be compensated for in the tool path

but not always. I was able to remove most of this backlash once I got hold of a service manual for the machine.

 

I use Fusion 360 software for the CAM. It allows a lot of control over the tool paths and is free for hobbyists.

Unfortunately they expect backlash compensation to be done in the machine firmware which is not the case

for my machine. 

 

Be aware that the stepper motors only give open loop control of position. With a laser cutter this is not a big

problem because the mechanical forces are unaffected by the material being cut, but with an engraver/mill

the forces depend on the material and depth of cut. More expensive machines control position with servos and

encoders and can compensate for this, with steppers you will have to be more conservative with

cutting speeds and depths.

 

I hope you find this relevant. I will take some photos later today and upload them.

 

John

[BG John]

Thanks John. It's useful to know that even a far more expensive machine has its challenges for doing this sort of work. In a way, it makes the Silhouette cutters seem even more impressive for the price. If only they would cut thicker material, although presumably they would then start running into problems.

 

I had a quick look at Fusion 360, but it's for Windows 64-bit only (or Mac). I've got 32-bit Windows, or 64-bit Linux, so it would involve more expense and hassle with computers.

 

I'm tempted to buy one and see what I can, and can't, do with it. The alternative to not having one at all is to laminate thin parts from the Silhouette, that other people do successfully, but it may allow me to do things that the Silhouette won't. I'd like to be able to mill circuit boards, as I'm using Arduinos for most of the electrical bits on my layouts, and some simple PCBs designed for the job would save a lot of intricate wiring. The other reason to buy one is that it seems an easier way to learn the technology than to build my own machine. I can consider that later when I've got my head round it.

 

Still thinking, but need to decide soon!

[teetrix]

Maybe out of your budget, but IMO a reasonable quality for a reasonable price:

 

https://www.stepcraft-systems.com/en/products/desktop-systems

 

They are available as RTR Machine or Kit, the latter saves you a considerable amount of money. There are choices regarding the software and the spindle motor. Have a look at "tools" too!

 

Michael

[BG John]

Unfortunately, it's way out of my budget Michael. If I knew I had the skill to make parts to sell, it would be a different matter, as I would make things to help recover the cost. If I discover I do have that skill, and there seems to be a market for them, it's something to consider later.

 

My feeling with these cheap machines is that it's partly a learning process. I could easily spend £200 on an introduction course to just grasp the basics, or I can buy a machine and learn for myself. If it turns out to be like the Silhouette machines, where railway modellers have pushed it far beyond what it was intended for, that would be great. I hope that happens. If not, I'll have learned a lot about the hardware and software, and will have a set of the type of components that I can readily buy more of. That could put me in a good position to build the type of machine that really suits what I want to do, or rebuild this one. If the components aren't up to the work I want them to do, I can use them on a specialised machine for a particular lightweight job, or use them for fiddle yard traversers etc.

 

I'm aware that I may struggle with the software, which may be a lot better with a more expensive machine, but that's part of the learning process, and a reason that I want a machine that's compatible with Arduinos, that I'm getting into anyway.

 

My inclination is to buy one, with quite low expectations, knowing that I may waste some of the cost if it's no good, but that it has a lot of useful components for other projects. I'll get it to work, sooner or later, and learn a lot in the process. And if I'm lucky, it may even do what I'd like it to do! The alternative is not to buy one at all, and I may miss an opportunity to achieve things I want to do, and learn new skills.

[rdr]

there is a Denford Novamill on Ebay atm and is still at reasonable money. Trouble is the sale looks like it's being bid up and the identities of bidders are being blocked, often a sign of a protected sale.

[BG John]

It was my birthday yesterday, and I didn't get the presents I really wanted (not that I was expecting them!), so I ordered one to partly make up for it! It's on its way from Germany, and should be here late next week. I'm hoping I'll avoid having to pay VAT etc. on it, as it's from within the EU, and the eBay listing strongly suggests there's no VAT to pay, but to my devious mind the wording is ambiguous.

 

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