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Build Your Own PCB Milling Machine
Posted by
timothy
on Sun Mar 30, 2003 07:59 PM
from the for-large-values-of-it dept.
from the for-large-values-of-it dept.
mwandel writes "It used to be that one off amateur printed circuit boards were all etched in acid. A lot of companies nowadays use a special form of milling machine to mill them out of solid copper clad circuit boards. This guy Jonathan Westhues built his own PCB milling machine out of various parts, with a laminate trimmer as the milling head. Lots of other neat hacks on his Webpage as well."
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Build Your Own PCB Milling Machine
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Amateur (Score:1)
Whatever happened to the guys that were going to print out boards on inkjet printers?
Also since these would be milled, they would be called MCB's. Get it straight.
Milling machines, while a marvel of modern technology in their own right, cannot create multi-layered circuit boards, unless you ignore the obvious extra steps involved. Sounds like overkill, and a solution looking for a problem.
Re:Amateur (Score:4, Informative)
Also, It is not difficult to make a double sided PCB with a milling machine. There are many times in circuit board design that you don't need more than one or two layers. This is a solution that solves a lot of smaller problems every day.
Re:Amateur (Score:5, Interesting)
Acid etching produces a functional board, but it simply does not look good, and you can't make 100 boards that are exactly alike. The lines are almost straight, the edges are not perfect, and if you are on a contract to deliver a product, this is not an option. Examples of where a milling machine is one of the best solutions: a university lab where the researchers are under government/industry contract and are supposed to deliver a working prototype or a small business with a military contract (small volume products).
I worked for a startup company for a while, and part of my job was to work on a QuickCircuit [t-tech.com] milling machine, and that thing had milling bits that were 4 mils thick (comparable to hair). You can hardly reach this precision with acid etching. I also adapted the machine to dice wafers, which replaced the company's practice of using an exactoknife
If you are in the IC design business, testing cheaply is of primary importance. You can get a full setup for producing boards for less than $10K. How's that compared to billions of $$$ for setting up an IC production plant? And if you are in the RF design business, you need the precision so that a crappy board does not screw up your high-frequency measurements.
Of course, milling is no option for producing high-volume PCBs with many layers, but don't think that ASUS spent months to design such a board to test their new motherboard design. First they have to verify that design works, which is done with a cheap PCB design, one that would hook up the ICs. Only after that stage can the final PCB design begin.
As long as the Z80 or 68K processors are still in use, simple PCBs will be here, and we need a cheap and fast way to design and make them.
Mirror (Score:5, Informative)
(http://elitemrp.net/)
Here is a mirror:
http://mosascii.com/sd/pcb/index.html [mosascii.com]
(The mirror should remain up for a few days, unless my site gets slashdotted heh)
milling machines are cool (Score:3, Interesting)
More people need to be able to make their own parts out of steel and plastic. The problem is cost. It's curious that a country that is inventive as ours doesn't have some type of affordable CNC(computer numeric computation) milling machine.
Affordable metal cutting lathes are expensive too.
Re:milling machines are cool (Score:4, Interesting)
You underestimate what it take to make a good mill. A none computer controlled Bridgeport Vertical Mill will set you back 16 grand depending on how you option it. There are not a highvolume thing. It takes massive peices of perfectly machined metal to do this. Theres a lot to it. You can't just cheapen one up without it becomeing well cheap.
Adding Computer Numeric Control is not so easy. Though i'm sure if someone wanted to do it it would not be impossible. But there is a heck of a lot to G code (what runs CNC's). You'll be working the bugs out for a while. And then you still need a CAD program to pop out G code, thats a few grand there at the cheapest level. Granted if you want to spend a lot of time you can code it by hand. Many machinist do much of the G code by hand, but they do that everyday.
There are reasons CNC's aren't cheap, Mainly the fact everything about them is expensive. If you ever get to see a real high end CNC mill or lathe going you will understand why the cost $100K to a million bucks. Watching one at work will blow your mind. Especialy if you stick your head in it.
Re:milling machines are cool (Score:5, Interesting)
(http://www.foobarsoft.com/)
As for CNC not being easy, it's not easy, but it's not impossible. Especially if all you're doing is PCBs. How expensive is the software? Dirt cheap. You can use the free version of TurboCAD to make your parts. You export them as DXF files. Then the program that controlls your motors can convert that to gcode for you (or you can use another piece of software). You can get free DXF->GCODE converters that work quite well. You can also get free software to run your motors, or nice commercial programs for $20.
It's true that a "real" CNC machines start in the 10s of Ks, but you can make one that will do just about everything a hobbiest will ever need for just a little. For more information see my other posts to this discussion, or see John's [crankorgan.com] website.
Re:milling machines are cool (Score:5, Informative)
I don't think you could reach
slashdotted already (Score:2, Funny)
(http://mork.ca/)
2 comments so far and its already down. What's the point? The article might as well be yanked all together.
There are easier ways (Score:5, Informative)
Re:There are easier ways (Score:4, Informative)
ExpressPCB [expresspcb.com]- Has an offer that will let you make 3 3.8"X2.5" 2-sided boards for about $60, as well as a more general off that's not too much more pricey. They have their own board design software you have to use, which is a bit primitive but adequate for hobbyist use, though it's a problem if you were to ever want someone else to make your boards.
Advanced Circuits [4pcb.com]- Has a deal to make 2-sided boards for $33/ea, min qty 3. These boards have a solder mask, which is required for dealing with fine-pitch SMT parts, and makes your board all pretty and professional-looking ;-)
Sierra Proto Express [sierraprotoexpress.com]- Has a similar deal to Advanced Circuits, but also has a good price to make four-layer boards.
Some general notes- I've used the first two, and it worked alright, but I haven't tried the third one. The latter two require Gerber and Excellon data- this is the standard format for PCB plotting and drilling information information. Essentially any board layout software should be able to generate them. However, it is not trivial to figure out what precisely to send the board manufacturer- you can't just blindly trust your layout software to do the Right Thing. I keep meaning to write a little tutorial on my hard-won knowledge about this, but I've never gotten around to it :-/
Re:There are easier ways (Score:5, Insightful)
(http://slashdot.org/)
Granted it's only double sided - but at that it's wonderful. Wow, no more chemicals! I've always-forever wanted one of these but the pro milling machines are out of my league.
Do It Right - John Has Great Plans (Score:5, Informative)
(http://www.foobarsoft.com/)
If you want to build a machine to mill circuit boards, do it right. Build a machine designed by John C Kleinbauer [crankorgan.com]. The Brute [crankorgan.com] is designed to make PCBs cheaply. I recently bought some of John's plans (well worth it) and they are quite nice. They are very well done, easy to understand, don't need things that are exotic and hard to get (if your in the US). He includes a booklet on how to mill PCBs with The Brute, or you can order it seperatly. He even maintains and activly participates on his forum, Hardware Store CNC [ezboard.com].
I've started to build a brute, and things are going pretty well considering I'm doing this in my spare time with only some time to work on it. If you guys are like me (I really like to build things with my hands) this is a ton of fun. I can't wait to get it running so that I can make PCBs, robot parts, a wooden clock [woodenclocks.co.uk] and more.
It's a shameless plug, but.... (Score:3, Informative)
(Last Journal: Thursday August 23 2001, @09:23PM)
I'm sure this will kill his pipe, but here is a link: www.cnczeus.com [cnczeus.com]
It's listed in google as well, so you may want to check that out if/when the pipe goes dead from the load.
question? (Score:1, Redundant)
(http://www.livejournal.com/users/sinistertim101 | Last Journal: Saturday March 24 2007, @12:32PM)
Acid etching is nearly extinct (Score:4, Interesting)
(http://slashdot.org/)
Electronics Enthusiasts... (Score:5, Insightful)
For those new to this hobby... here are some publications that could be of great value to you:
http://www.nutsvolts.com/
http://www.circu
http://www.poptronics.com/
Anyone know of any others?
Re:Electronics Enthusiasts... (Score:5, Informative)
http://www.goldmine-elec.com/
http://www.alltr
http://www.allcorp.com/
http://www.ne
http://www.jameco.com/
Try to never buy from Radioscrap. Overpriced and crap quality...
I've ordered from Alltronics before. They have a $15 minimum order, and sometimes an order may be delayed if something you requested is out of stock. They answer your e-mails rather quickly, though.
Jameco also sells the seemingly elusive PCI prototyping cards [jameco.com], though they're pricey ($70). Anyone know another supplier of these? (They're also good if you're looking to pick up a 266MHz PII motherboard for $20)
=Smidge=
Re:Electronics Enthusiasts... (Score:5, Informative)
As much as I'm annoyed with Radio Shack for turning into a toy and appliance store (they used to be an electronics hobbyist store), they do still have a handfull of items for the electronics tinkerer.
I'd recommend picking up all of their Engineer's Mini-Notebooks to start with.
I'd also recommend checking out some of their X-in-one kits... I think they have a 300-in-one now (I hope they haven't stopped making these).
They have all kinds of example circuits that you can make by hand wiring (read: no soldering) the circuits together - and some of the examples are kind of cool for a beginner. I started with a 150-in-one kit (it was the biggest at the time) way back when I was a teen.
After this... if you want to get into digital electronics, pick up the TTL Cookbook and CMOS Cookbook by Sam's.
If you want to get into audio electronics, pick up the Audio IC OP-Amp Applications (also by Sam's).
If you're a musician, there's a VERY cool one called Electronic Projects for Musicians by Craig Anderton. Use this one with the above audio book to come up with some really cool guitar effect "pedals".
I hope this helps!
I could see where this could be handy (Score:1)
For computer hacking stuff, or for audio, this might be a handy thing to have.
Coming Soon! (Score:2)
Useless (Score:3, Informative)
(http://www.lib.ru/)
That's all well and good.... (Score:2)
(Last Journal: Saturday June 12 2004, @11:07PM)
And for the real, hardened professional. (Score:4, Interesting)
(http://caladan.nanosoft.ca/)
The most serious problem comes in from the really high-end etching systems. Photoresist is fine with ferric chloride, but when you start using something like an acid-peroxide etchant, it will actually eat many "resist" inks. The resist pens become TOTALLY useless, for example.
And so this is where the old technique of serigraphy comes in. This is the "screen-printing" that makes the name Printed Circuit Boards. The resist ink used on the actual board is usually just some form of lacquer, which holds up well to even the harshest etchants. A stencil is prepared on a screen, usually through a photographic process. Since the screen resist doesn't have to deal with the same harsh chemicals, it is generally much more environmentally conscious and cheaper than PC-Board photoresist.
I actually set up to do this method myself, in a semi-hobby context. I had some previous experience with serigraphy, and the acid/peroxide system was cheaper, far more effective, and much easier to dispose of than the ferric chloride. On the flip-side, it will eat virtually anything metallic and smells aweful (it isn't much of a health hazard except in the sulphuric/peroxide system, but should be ventilated nonetheless), so it's not for the faint of heart.
Milling vs. Etching (Score:1)
(http://www.l4l.org/)
Am I the only one who read this as (Score:1)
Recursive construction (Score:3, Interesting)
(http://neil.fraser.name/)
CNC Milling Machines (Score:2)
(http://www.urbex.org.uk/)
I used a small CNC miller to produce two complex alumnium plates that I used to produce a winch. It was complete overkill, but I was bored, and it did a very good job.
It had dodgy software and the sheet I was using was too large (X and Y) to use in the machine, so I had to make a jig using MDF and steel rod to locate the plate, so that it could be flipped, and the machine used to cut material much bigger than it was designed for.
The software and PC controlling it was updated last year, and now it can accurately profile 3D shapes. There are obvious restrictions, such as no undercutting (unless you use special bits, which is awkward). You can use opaque acrylic and etch photos onto it, with the darkness being converted into depth. By then holding it up to the light you see an image. Quite a neat idea.
I could see it being used for PCB production, but to be honest, it wouldn't be much use for anything small. It is very accurate, without a doubt moreso than the homebuilt one, but even with the smallest tips, I can't see SOIC outlines being milles with enough precision to be used. And most PCBS have some sort of surface mount components now.
I also see problems with raising the edges of the copper tracks slightly with milling. This would make surface mount components hard to get flat on the board.
Isn't it a salt? (Score:4, Informative)
Isn't Ferric Chloride (the stuff you buy in bottles at Radio Shack, or at least I did when I was a kid) actually a salt? FeCl... looks like a salt to me!
Re:Isn't it a salt? (Score:5, Informative)
Yes, it is a salt. Copper is more reactive than iron, so the etch works by the chlorine trading iron for copper. The "filings" left after etching are the iron that was freed in the reaction.
Some folks see it anything that 'eats' away at something as being caused by an acid, even if no acid is really involved. Wouldn't it be nice if chemistry was taught? And taught in a way that was effective?
Milling machine (Score:2)
(http://slashdot.org/ | Last Journal: Wednesday January 04 2006, @09:14PM)
Now they just need to make a low cost device for placing and soldering SMD components on the boards.
UV Light does the trick (Score:3, Interesting)
Use some chemicals (stored in a safe location and brewable in your own home) and you've got a nice PCB for you to use.
There is a necessary market for milling machines. (Score:1)
Acid etching produces a functional board, but it simply does not look good, and you can't make 100 boards that are exactly alike. The lines are almost straight, the edges are not perfect, and if you are on a contract to deliver a product, this is not an option. Examples of where a milling machine is one of the best solutions: a university lab where the researchers are under government/industry contract and are supposed to deliver a working prototype or a small business with a military contract (small volume products).
I worked for a startup company for a while, and part of my job was to work on a QuickCircuit [t-tech.com] milling machine, and that thing had milling bits that were 4 mils thick (comparable to hair). You can hardly reach this precision with acid etching. I also adapted the machine to dice wafers, which replaced the company's practice of using an exactoknife
If you are in the IC design business, testing cheaply is of primary importance. You can get a full setup for producing boards for less than $10K. How's that compared to billions of $$$ for setting up an IC production plant? And if you are in the RF design business, you need the precision so that a crappy board does not screw up your high-frequency measurements.
Of course, milling is no option for producing high-volume PCBs with many layers, but don't think that ASUS spent months to design such a board to test their new motherboard design. First they have to verify that design works, which is done with a cheap PCB design, one that would hook up the ICs. Only after that stage can the final PCB design begin.
As long as the Z80 or 68K processors are still in use, simple PCBs will be here, and we need a cheap and fast way to design and make them.
PC Motherboards (Score:1)
Polychlorinated Biphenyls (Score:2, Funny)
Don't bother (Score:2)
(http://www.animats.com)
Realistically, PC boards are made by sending output from a board design program to a service that makes boards. It's reasonably cheap, turnaround is good, and you can get double-sided with plated through holes, which is what you want.
Toner transfer methods are for people who like looking at their boards under a magnifier and doing rework. Do it yourself photographic methods work better, but few people bother any more. Anybody still have one of those small etching tanks with the aquarium bubbler?
A related business is making front panels. [frontpanelexpress.com] Send out your design and let a computer-controlled punch make all the connector holes. They also etch the lettering and anodize.
Clever of you (Score:2)
pretty unfortunate (Score:4, Informative)
(http://restiffbard.com/)
this is no longer humorous. As much as I often enjoy the +4 comments on certain articles reading slashdot is pretty much no longer worth the frustration of not being able to RTFA.
Can't wait till this article moves down the frontpage.
To plot.. (Score:2, Insightful)
(http://di.cx/)
Advanced: BGA and multilayer (Score:1)
(http://ered.info/)
What would be required for BGA work? what sort of accuracy? does BGA automatically imply multilayer, or can you route between the contact patches? what sort of "fill rate" do the solder balls form? do you need to add more solder, or do the solder balls themselves suffice?
Also, does anyone have thoughts for a BGA capable DIY soldering system? you'd have to hold the parts in place, i assume? heating elements: what's used by the big boys? how can you get a system that would provide the appropriate ramp up in temperature from that system? pizza ovens come to mind, but maintaining the constant and low delta-t has been described as an absolute requisite.
moving on to multilayer...
*gulp*.
i'd think this would vaguely just be like solder masking - with which i happen to have no experience either. just mask a nonconductive coating, then glue. what adhessive is used? what is done for interboard connectivity?
and where do you find thin PCB for use in such a system? somehow those 6 layer nvidia boards (random guess) are just as thin as my single layer ISA serial cards (bless them both).
Myren
This is neat (Score:1)
(http://www.ldwp.com/)
My current CNC mill is a MaxNC [maxnc.com] NC-10. At around $1,300, it was the best deal I could find. Its a little slow, and not the best thing by any means, but works nicely. I'm going to be selling engraved desk signs, I'm going to use it for engraving. I'll probably eventually do 3D image engravings(depth mapping), but at first I'll just do lettering.
I've made a couple keychains of Tux, some 3D statuettes, several more keychains, some lettering on wood, some robotics parts, etc... They all look really nice!
Actually, my biggest complaint about that machine(the NC-10) is that the effective X work distance is only about 6 or 7 inches. Its big enough for small work, like engraving signs, but I'm thinking about building a much bigger CNC router with a 5x10ft(or something) table sometime.
One thing I have to say to everyone who is going to buy or build a mill. Software for these can cost over $1000! You need the CAD program to design the item, the CAM program to create G-code from it, and the actual CNC program which will come with the mill, or be freely available. MecSoft [mecsoft.com] did offer a free "lite" version of their CAM program, but don't seem to anymore(Luckily, I have it archived), but that is what I'm using.
Vinyl and Inkjet (Score:1)
Found a printer late last year that has a strate paper path. A Lexmark i3. Cramed a CD and it actualy printed on the top of it. Did try a test with paper and printed test in some etching solution and it seam to pass ok. Now if I can get some time will cram a pc board and print out a circuit! Be nice if I could replace the std ink with a copper based and just print the layout.
Manual? (Score:1)
(http://sharpy.xox.pl/ | Last Journal: Wednesday September 14 2005, @02:12PM)
Re:okay, where can I buy a pcb milling machine? (Score:2)
Replace the pen with a high-speed cutter and then you can interface to the plotter quite simply through the RS232 port or whatever the plotter supports.
Here's a plotter on eBay [ebay.com] that might be a good starting point.