Small CNC matchines sold around the web - Page 1
Forum section: electronics / general

author: MrAl
author_rank: Super Contributor
timestamp: May 03, 2015, 08:00:56 pm
content: Hi there,Anyone try any of these small CNC machines sold around the web?They are less than 1 foot by 1 foot or so, and can probably be used to make PCB boards.They sell for around 500 dollars (USD) and up.Thanks much,MrAl

author: alank2
author_rank: Super Contributor
timestamp: May 03, 2015, 10:19:27 pm
content: Hi,I use one of these for cutting plastic enclosures - see their forum for more info:http://www.microcarve.com/mcMV1.htmlGood luck,Alan

author: MrAl
author_rank: Super Contributor
timestamp: May 04, 2015, 02:15:49 am
content: Hi,Have you (or anyone else here) ever tried to make a PC board with one of these machines?That would mean clamping down a blank PC copper clad board, then milling away the spaces in between the copper trace runs. It could take some time, but with one-off prototype boards who cares.What i am really wondering is if this works good or just so so or not at all.

author: John Coloccia
author_rank: Super Contributor
timestamp: May 04, 2015, 02:30:15 am
content: I get professionally made, 1-off prototype from my normal board house, and they cost me about $140 for two of them, with silk screening and soldermask. And they ship in a couple of days...If I'm willing to wait 2 weeks, and can live without silkscreen or soldermask, I get them for about $90 for a pair.....and if I'm in a production run, can wait two weeks, and want full solder mask and silkscreening, I can buy 100 of them for about $650.And I get properly plated holes/vias plus some slots if I need them.and if you're willing to forego any sort of real quality, you can get them much cheaper than this from some Asian board house, I think (not an option for me, but possibly quite useful for others)IMHO, buying a CNC machine to make boards is a complete waste of time and effort. If you're really just a beginning hobbyist with time to spare, you don't need the CNC at all. If you're at the point that a CNC could possibly be useful, there are much better options, IMHO.But that really is just my opinion.

author: MrAl
author_rank: Super Contributor
timestamp: May 04, 2015, 12:33:24 pm
content: Hi John,Well, i think a lot of hobbyists dont want to have to pay 100 dollars for 2 boards, or even 50 dollars for two boards, but yes it would be easier to have someone else do it.I think a lot of hobbyists want to make mostly one-off boards and probably each one is different in some way, and probably a smaller board like 2x3 inches or maybe 4x6 inches tops.Currently small blank boards are less than 5 dollars each, and so we could probably make two boards the same or different for about 5 dollars. That means we could make maybe 20 boards for 50 dollars. Yes it would take longer for the boards to eek out of the machine, but many would not mind waiting an hour or so for the completed board.I realize it depends what you intend to do with the boards too. When i worked in the industry we sent out for all boards which included having the layout done, and some of them were as large as 12 by 24 inches and double or triple thick material.

author: langwadt
author_rank: Super Contributor
timestamp: May 04, 2015, 01:26:29 pm
content: prototype pcbs are so cheap now (like $10-$20 for 10pcs) that it doesn't make sense to make your own unless you need it NOW and can live with the very limited specs, no plated holes, no solder mask, etc. and don't forget that the price of consumables quickly add up for CNCing PCBs, milling cutters and drills don't last very long

author: PlainName
author_rank: Super Contributor
timestamp: May 04, 2015, 02:58:43 pm
content: QuoteI use a Sable cnc which is similar to the ones you describe, and I've also used a Peatol, which is a bit bigger and aimed at 'proper' (albeit still light duty) milling.You've probably already noticed that there are plenty of nay-sayers, and one wonders if they've ever actually tried to mill PCBs. There are plenty of people milling PCBs but are unwilling to get into arguments about why what they're doing is so impossible/wrong/perverse that they don't often post to this kind of thread and the deniers get all the screenThe other thing to note is that deniers always seem to assume that one will either mill every single PCB ever used, or none at all (which probably explains their stance). I mill some but also get boards made at itead - it depends on what I am wanting to do, the complexity, time constraints, etc.Milling PCBs is better where you might breadboard a prototype, or a part of a prototype. Typically, mine will be of a complexity which is routeable single-sided (or with just a couple of topside links). Using PTH resistors and capacitors improves the routing possibilities, so I tend to use those (but SMT chips).It's also useful to remember (which the deniers naturally forget) that milling PCBs is just one thing: you can cut cases, front panels, mill signs, etc - it is not a one-job wonder.For more complex or 'finished' designs I'll just send it off to itead and wait the 4 weeks. The thing that bugs me about that is often finding a cockup in a design just after I've paid itead to make it, or just before the PCBs arrive so that's another 4 weeks before I can do anything. With a milled design I can also make a cockup, but I can have a fixed one in half an hour so it's much less of a downer.Don't get the wrong idea from all this, though: getting to the point where you can consistently run off PCBs is not trivial and takes a lot of dicking about. There are many guides dealing with this, but ultimately they are only guides and you'll spend some effort on finding out the unique system that works for you. You might well decide that it was a bum rap and you're better off etching, or just forgetting all this DIY rubbish and send your designed to a Chinese PCB maker. But make that your choice and not some armchair warrior's wish.

author: MrAl
author_rank: Super Contributor
timestamp: May 05, 2015, 03:01:54 pm
content: Quote from: langwadt on May 04, 2015, 01:26:29 pmHi,Where do you get 10 pieces made for 10 to 20 dollars?Yes some people dont believe in CNC, but there are many that already have machines that they either bought or built themselves. Building one is interesting in itself.

author: wraper
author_rank: Unknown
timestamp: May 05, 2015, 03:29:52 pm
content: Quote from: MrAl on May 05, 2015, 03:01:54 pmElecrow, for example.

author: alho
author_rank: Contributor
timestamp: May 05, 2015, 03:43:34 pm
content: Can I grow lettuce on my window sill?NO!!! Buying a window to grow lettuce is a waste of time and money. I can get lettuce with sliced tomatoes and salad dressing from local restaurant for 10£ and if you don't care about quality you can get lettuce even cheaper from super market. And if you want to grow lettuce at home there are better options, like a 30m2 greenhouse with at least 8 1kW HPS lamps and don't bother trying to grow in soil you'll need hydroponic water system to get good results.Quote from: John Coloccia on May 04, 2015, 02:30:15 amSo 500$ CNC would pay it self in 3,5 years if I made one board per year. Let's make that two boards to cover cost of materials and consumables. And not including anything else that I might use it for. Also local prices might be higher in other countries if there even are board houses that are willing to do one offs.Couple of hours shouldn't be problem for a CNC.CNC seems quite attractive option to me. Relatively clean (boxed cnc with dust control). Fast if setup is ready (only tool change and PCB placement needed) . One off hobby projects so quality of board is never a real issue.I'm not willing to dedicate an area for etching so there's allways little setting up to do. CNC would just sit on a table in garage ready to go.But I wouldn't buy cnc just to make PCBs it's just an extra thing that it could be used.So... How good these 500$ china machines are for PCBs or generally doing anything? Anyone got one?I'v been planing to built my own cnc. 200€ seems to be minimum (not including useful stuff that I all ready have) which is rather close to chinese prices so I'm not sure is making my own worth the effort. Of course building my own would be more about building something rather than getting a finished product.

author: JackP
author_rank: Regular Contributor
timestamp: May 05, 2015, 04:34:48 pm
content: But for lots of people, single sided, no solder mask is a big issue. I back the idea of a CNC, seems a quick way for prototypes (as well of other things of course), but there needs to be an easier way to add more layers IMHO.

author: mc
author_rank: Regular Contributor
timestamp: May 05, 2015, 05:13:48 pm
content: I'm going to guess the OP is looking at your typical 3040 size machines.To be blunt, they're typically rubbish. I do however own one, yet it's never been used to cut anything as I bought it for the sole purpose of probing parts.Pay the extra for one with ball screws (add a Z to the model number IIRC, so 3040Z), as acme screws are rubbish. Yes you can do all sorts to remove backlash from acme screws, but they're still inefficient and they'll ultimately give you more hassle than money you'll save.Replace the thrust bearings, with a good brand of bearing, as the typically fitted original bearings are truly cheap and nasty. The thrust setup is far from ideal, however it's adequate for the light loads these type of machines will produce.If you plan on using it for prolonged periods of time, consider getting one with a water cooled spindle. They last far longer, are much quieter, and are more powerful (main benefit is more torque at lower speed).Check all the stepper wiring, as mine had various connectors which were very poorly crimped. This wasn't a problem for me, as I rewired everything anyway, which brings me on to the next point.The supplied controller is pretty rubbish using mediocre stepper drivers, however they generally last OK provided you don't abuse them. And if they do die, it's a good excuse to upgrade to something more reliable.If they do supply a license for Mach3, it'll most likely be a dodgy copy, so don't expect any support for the Mach guys until you buy a proper license. Off course, you could opt for LinuxCNC.I need to go, but that's a brief summary. I'll add more later if I think of anything.

author: vinicius.jlantunes
author_rank: Regular Contributor
timestamp: May 05, 2015, 05:50:50 pm
content: I think @Fred27 did something like this (adapt a CNC for PBC milling). It's all in his blog - I thought it was one of these chinese 3020, but he actually did it with a Proxxon.https://0xfred.wordpress.com/2012/02/12/proxxon-mf70-cnc-mill-conversion/

author: mazurov
author_rank: Frequent Contributor
timestamp: May 05, 2015, 08:37:51 pm
content: Quote from: MrAl on May 04, 2015, 02:15:49 amI have this machine and mill PCB on it occasionally; I posted pics of the results on this board some time ago. While in most cases ordering a board from a place like OSH Park makes more sense to me ( 6 mil for $5 per sq.in for 3 copies ), milling becomes quite a bit cheaper when I need large (A5+) board or a batch of simple ones or I need to study a certain structure like a CPWG or a non-trivial antenna, where I can cut and measure 20 times a day, say.The mill is mainly used for standard milling jobs; buying this kind of machine to mill PCB would be silly.

author: atferrari
author_rank: Frequent Contributor
timestamp: May 05, 2015, 09:33:15 pm
content: Hola MrAlGood to meet you also here!Many many years ago when these peoplewww.lpkf.comstill had a local representative I could watch a demonstration of one of their machines. It was very impressive! Crazily fast. But, since then, they play in the top league of PCB milling.It was then when I became in love with the idea of getting simple PCBs in a matter of hours.In my voyage to Europe (Nov 2014) I failed for few hours to reach Iserlohn (Germany) with time enough to buy one machine from themhttps://www.stepcraft-systems.com.Their top guy, Peter Urban, is also the technical head ofhttp://www.usovo.de/shop/who produced a kit to mod Proxxon machines for PCB milling for several years. Basically, as far as I could read with good comments.I understand they have all basic problems solved even software and USB connection.Two things to say: last time I asked, the Stepcraft had not automatic tool changer and prices were, for sure, higher than any generic chinese one, which I would not dare to try.Maybe near the end of this year I can get one.

author: Fred27
author_rank: Unknown
timestamp: May 06, 2015, 07:28:21 am
content: Quote from: vinicius.jlantunes on May 05, 2015, 05:50:50 pmI decided to get and convert this mill after stumbling across it when looking at methods of home PCB production. I milled a few PCBs - through hole is no problem and SOIC/0805 is OK. One plus of milling boards is that you can go straight to drilling and routing out the boards on the same machine and alignment is perfect. This sort of thing is no problem:https://0xfred.wordpress.com/2012/04/17/peelight-v1-1/However, I then came across UV dry film solder mask and gave that a go. That really showed up the fact that milling gives a greater variation is the contours of the board. It meant it was harder to get the soldermask on evenly. Also using a small V cutter means the variation in cut depth also gives variations in cut width. These things are possible to solve in software by probing the board but I must admit that as I had the UV gear for the soldermask I switched over to UV exposing boards. I get better results this way, but I'm now struggling to accurately align the drilling for small vias.Long story short - I got the mill for PCB routing, but kept it for all the other stuff it does like enclosures.I'm thinking of getting a 6040Z which is probably why @vinicius.jlantunes thought I had a 3040.

author: MrAl
author_rank: Super Contributor
timestamp: May 06, 2015, 09:20:27 pm
content: Quote from: atferrari on May 05, 2015, 09:33:15 pmHola,So do you have any kind of machine now, and if not, how much do you think it would cost to get one of the ones you are talking about now?Sounds very interesting. I have also been thinking of updating my machine, which i never finished, with a new Z axis that has more guts to it so it can do light duty milling which should be good enough for PCB work. I see nice ones on the web though that are smaller, more compact, and am tempted.I have other things going on now too though so not sure when i will be able to get back to this. Hopefully in a couple months.

author: Sigmoid
author_rank: Frequent Contributor
timestamp: May 07, 2015, 08:04:30 pm
content: Quote from: John Coloccia on May 04, 2015, 02:30:15 amI've got the feeling that I've stumbled into a time tunnel to the early 90s, or a parallel universe. That sounds super expensive!http://imall.iteadstudio.com/open-pcb/pcb-prototyping.htmlWhat kind of PCBs are we talking about?

author: John Coloccia
author_rank: Super Contributor
timestamp: May 07, 2015, 09:01:42 pm
content: Well, I just made one that's about 12" x 12"...basically the size of a large motherboard. But most of them are about 3"x4". I know I can get them cheaper, but I get my prototypes from Sunstone because then I can simply repeat the order to get a run of 100, for example, and I know that they will all be exactly like my prototypes. I also have a pretty low reject rate with them. It's worth it to me to pay a little more for the exact consistency between prototype and production. I've also committed to trying to keep as much work in the US as I can, because I think it's the right thing to do as a business, and higher PCB costs are one of those things I can reasonably absorb and still keep production here, so I do.But you're exactly right. You can get PCBs dirt cheap these days. There's very little reason to consider messing around with CNC when you can get professionally made, finished, solder masked, silk-screened boards for very little money.And for the record, because some people were wondering, yes, I did own a CNC machine...probably one much larger, more powerful, stiffer and more accurate than what most here are considering. I didn't say it's impossible or it won't work. I said from a practical standpoint, it's hard to come up with reasons to justify it. Now, for the hobbyist that just wants to play with a CNC machine and have fun, well get a CNC machine and have fun, no justification nescessary! That's all I'm saying. Go into it with the idea that you're having fun and learning, and then there will be no disappointment if you never realize any real ROI compared to the other options.

author: MrAl
author_rank: Super Contributor
timestamp: May 07, 2015, 10:18:01 pm
content: Hi,Well what would you say would be the cheapest price to get a 2 by 3 inch board done, or a 3 by 4 inch board maybe, including shipping, in the USA just delivered to a USA address?Quote some actual real life dollars and cents and we'll compare right here and now, and that is for a SINGLE piece, not 10 billion boards :-)

author: atferrari
author_rank: Frequent Contributor
timestamp: May 07, 2015, 11:58:21 pm
content: Quote from: MrAl on May 06, 2015, 09:20:27 pmYes, I still do not have one.I see that now, they have more options in their catalog. What I believe is the 2/300, maybe just the "300" on Novemebr last year, goes for some 800 Euros. Please check to be sure.Just to be sure, pleaee check their USB soilution which seems real and say goodbye to the parallel port. As I can see they entered the 3D market as well.Hope you can buy one!