Want to buy a CNC mill kit, need some advice

[asimov-solensan]

Hello,

So I really want to get one of those. I have absolutely 0 knowledge about them and since in this forums there is all kind of hobbyists I thought that it may be a good place to ask.

First a bit of background:
I know my way around mechanization. I usually work with nylon, polypropylene, aluminum, steel, maybe iron and wood. Always work with hand tools and handcrafted designs although I know 2D cad and

I usually do kludges that go from custom pieces for bikes to furniture, customizing PC cases and other electronics, any kind of repairs and customization that may be needed in a home (at least in a nerd's one).

99% of times the goal is to achieve resistance to mechanical stress, and I don't give a crap about aesthetics, that's why a CNC mill fill much better my needs than a 3D printer, hence the materials I use. Besides there is a 3D printing house at my town I can use if I need (if I learn 3D cad of course).

Now what I'm looking for:

A full kit. I may be able to buy engines or any electronics at my town but I don't want to lose time building the device, I want it to be usable as soon as possible.

The materials I told, steel usually only in thin sheets (2 - 3mm) but others I may need easily something that allows a thickness of 40mm and a long/width of 300mm, usually not in both dimensions.

I want something that I can use from linux, and if there is any tutorials to know which programs and how to use them it would be just perfect.

As explained this is for home use. I live in flat and space matters, the numbers I gave are mainly worst case scenario.

That's all I think. As said I just want to introduce myself to this world and have got some money saved that I want to spend into this. If links to amazon or any other shop shipping to spain are provided, much better.

Any advice is welcome.

 

[Bernd]

Please don't be mad at me.
(I'm in the metal machining busines & hobby since 1995)

But this CNC-mill kits at Amazon, E-Bay,... are most only toy's which are able to cut cardboard, polystyrene foam, soft plastic and perhaps soft wood.
They're only legit use is to use them as knife cutting router, PCB-router, PCB drill machine, 3D printing platform,...
If you are new to milling, do yourselve a favor and don't buy a kit.
It's extreme hard to adjust a mill correct.
Buy a ready build mill.


Milling is messy and loud.
Its advisable to use a mill in its own room in a cellar or seperate building.
Otherwise you'll find chips and unhealthy dust in the whole building / apartment.

Search yourself a maker space or similar first.
They are able to show you the basics of milling and what are the catches in buing your own mill.

If you are on your own without a helping hand, you'll only end up frustrated, because nothing works out correct.
Toolbits break, the parts don't looks well,....

If you really want your own mill, tace a guy / girl which understand the machining busines with you to the local shop and test the machine.
Don't buy in a internet shop if you're new to milling.
Because if something doesn't work, you'll be able to go to the shop and get help.
And you're able to throw the whole thing at the seller if he sold you chunk.

 

[levi]

As far as I've experienced, CNC milling machines tend to be quite beefy machines. Sure you don't wand a CNC router? Those tend to be much smaller, and with a bit of manual fiddling and adaptation could probably do much of the same stuff - just not quite as repeatable. But that's fine for small runs of things.

 

[Failbert]

Hi. I spent a lot of evenings over the last few months considering a cnc mill to buy, and later considering a cnc router (for wood) to put in a flat (ever since moving out from my hometown and losing access to dad's metal shop I miss machining), so I know well the itch.

But believe me, using a hobby kit/small router (sometimes called "cnc plotter" here), from what I've seen in action when looking for one to use for what I thought would be just small steel details, will barely cut the chase even for engraving text in sheet metal and maybe some jobs like neatly rounding a small corner of a pre-cut steel sheet. (edit: still, this is presuming You are making things not requiring high precision or perfect repeatability)

There are vids of steel being cut in small plotters, the one's of the size You'd see in a small ad agency or someone routing wood relief's, but it involves VERY long times due to the miniscule amount of material being subtracted (because of the mill's relative low rigidity compared to a big milling machine), oily coolant spraying or being applied as mist everywhere (almost everyone hates it even when it's containable at a workshop, imagine having this milky, smelly substance in the corner of your apartment), and an annoying, high-pitched noise- over multi-hour periods of time which You need to do a big number of runs with a small kit.

That said, You know best what You need and how much time can You invest (ie. endure). Like said before by a far more experienced forum member @Bernd, go to a shop and ask around.

Also if You wish to transition from 2D to 3D "drafting", and specifically have access to a windows pc with any version of AutoCAD from this decade, I'll be happy to give pointers on how to "go to the third dimension", which yielded good resulting .stl files so far.

 

[___]

That is awesome, I am eager to learn what you will find out and which machine you'll be getting. CNC mills are something I'd love to use, but the price, power requirements and expertise you need are holding me back.

I was researching this for a while myself and the only viable and reasonably usable open system for hobbyists seems to be the OpenBuilds platform. maybe look into that, but the experts on here can judge better if that stuff is worthwhile:
openbuilds.com
http://openbuildspartstore.com

they have a few options on how you can configure your setup, but you will need to build it yourself, including choosing an appropriate controller and the needed electronics, researching and buying a spindle, tools etc. the openbuilds.com site contains many contributions from people who have built a cnc machine and who share their bill of materials or even guides.

EDIT: you might be able to find complete kits created with openbuilds materials. one name of a machine that I heard a lot about is the ""workbee".

 

[asimov-solensan]

Thanks a lot for your answers.

Thanks a lot for the warnings about those kits on amazon ebay. They looked too good to be true and already was skeptic about them.

Regarding some points.

Repetability of pieces is not mandatory, but when I build some structures must the deviation between pieces must be small I guess that differences of 2-3 mm between pieces would be too much for my use case.

I can't afford a place dedicated to this. I have got an extra room in my flat but not enough to fit a full CNC mill, leaving aside noise and dirt from the thing.

Besides where I live there aren't any small workshops to ask for such things. Smaller places won't hear you if you don't ask for a 400 pcs order. Sadly this is something cultural. People here has no interest into this kind of things, even getting raw material or some tools is hard.

I don't know about a CNC router. As far as I understood the router is only useful for engraving or "delicate" jobs. What I do mostly is pieces cut at certain angles in 3 dimensions and then with holes here and there. I may upload some photos.

This openbuilds thing seems interesting project in itself but I want something to use with less effort.

Right now seems that it will be better to work as I have been doing until now.

 

[Failbert]

To clarify my previous answer: when I meant "cnc plotter", I meant something like this:
https://www.olx.pl/oferta/ploter-frezujacy-cnc-CID619-IDrmVYd.html

These are often assembled by dozens of self-employed makers in Poland and other countries because there is a local market: most smalltime enterpreneurs who need one are generally too poor to buy a brand-name machine, don't want to fiddle with making their own, and a low-quality Chinese CNC machine won't cut the chase (cheap imports can be very unreliable and I know it first-hand; I didn't research openbuilds otoh so not going to chime in here).

Most of these machines are marketed towards furniture workshops, carpenters and advert manufacturers. They *can* be used for steel (), but it's pushing it, or requires a machine specifically designed for it (THIS one looks nice and claims to be made for steel, but I haven't read any opinions on it)

Please post pictures if You can because it might give everyone a better idea of what is needed. And certainly many of us will enjoy looking at things being done .

 

[slaeshjag]

I've considered a Millright M3, but I'm still several months away from plonking down any money on one. Its $329 starting price quickly shoots into orbit when mandatory options, shipping and VAT is considered...

 

[Bernd]

I own one of this toys at home:
(The GP10050 in the video isn't mine, mine is electrolytic zinc plated.)
It's an german produkt.
I'm still at the adjusting and building mine & wish I would have build the ready build version.
(At work, I program small 3.5 axes ones with 4000mm x 1000mm x 1500mm work space)

If you wish for a much smaller mill as the shown, I would recomend a band saw or a scroll saw.
A band saw is faster then the small mills.
And more versitale too.

I would recomend a good industriegrade band saw.
Often used one get sold for a pretty small penny.

Don't buy the cheap band saws at the hardware store.
They are a pice of junk.

Mathias Wandel shows how to build pretty good band saws and other tools.
You could build a smaller version of the shown band saw.

I think a scroll saw and a laser printer for paper-tamplets is exactly the tool you need.

A cnc mill need to get programmed & pampered bevore good parts get made.
With a scroll saw or a band saw the parts are finish bevore the preperations for the mill are done.