printed circuit boards

I've just got started to. Probably the cheapest way is etching pen, a blank copper board and some etching solution (ammonium persulphate or ferric chloride) If you start doing finer work then maybe investigate the press n peel stuff.

Well, you'll need three things at least.

• You'll need PCB software, which usually requires input from a schematic netlist, but you certainly can enter a netlist by hand, but this gets very tedious with modern high pin count parts, and is very error-prone. But if you just want to make a board with a 28 pin DIP like a microcontroller, and some parts like resistors and LEDS, it should be fine.

• When your layout is done, your layout software can output photoplot files, which is what the people that physically build the PCB use to make the patterns. If you want to make your own boards, you'll need a way to transfer that pattern yourself onto a piece of copper-clad board. You can either print with a laser printer to something called Press'n'peel and transfer the pattern directly with a clothes iron (not a soldering iron :) ), or you print with a laser to a transparency and use special boards that are light sensitive to expose your artwork. You'll need a good UV source and some chemicals to develop the board. You also need to clean the board before to make sure the artwork is on there nice and good. Usually I use a sponge with an abrasive cleaner like Ajax, then I rinse with tap water for a minute, then pre-etch the board for 30 seconds-ish, then rinse again, then dry with a shammy.

• Once the artwork is on the board, you'll need some etchant to remove the unwanted copper. I still use ferric chloride because it's cheap and it tastes good. There are other etchants out there like ammonium persulphate, which is a powder you mix with water, but doesn't taste nearly as good. :) Etchants are fairly dangerous and can react wildly with metals, so you'll need nice plastic containers to hold the ethchant. I use dollar store food containers.

You are on your own as to which software to use. Google around for something called Eagle, people say it's good. Also, be ready to try several times before you get some joy. And always use a laser printer. I'm sure your school has a print shop or something like that. And do some visual tests first, print on paper and check to see if your parts line up on the printout, because I've seen something like +/- 5% variation in size for so-called 1:1 printouts. And for double-sided boards, try to get it all on one side, double-sided is too much trouble unless it's a ground plane.

Well, there is allready a nice explanation replied on how to make curcuit boards.

But then you still need to buy the UV lights, chemicals etc, which is expensive, I know that for a student everything is expensive.

But here is what I did when I studied:

Find a practical technical school (mid-level), the kind of education people do to become electronics service personal/repair stuff etc. Such a school usually has all the equipment, I was able to make my pcb's in the evenings at such a place when I studied, just material costs.

Good luck with it. Cheers, Jeroen.

Yeah, but that gets old fast. I used to use the direct transfer method, you know, those press on decals?

It would be really helpful to know whether you were interested in making a pc board as a prototype / breadboard, or whether you were interested in making production quantities.

Well, for the copper laminate itself, check : "

" under the "PCB laminate" link. 9" x 12" double sided for only $2.50 each, high quality.

For single-sided, just etch one side away...

Jan-Erik. (Yes, it's my site...) (Check out the carbide drills at the same time !)

Jeff Zimmerman wrote:

A good layout program like Eagle. A laser printer. And Press-N-Peel. Forget double sided as electro plating is a messy process, unless you spend the money to have the boards made by a shop. You can do double sided, by adding registration holes, and soldering the vias manually. But it gets cumbersome.

BTW, I think the UV stuff is for the birds.

You might want to check out my page at This uses an ordinary "Sharpie" felt tip pen and ferric chloride etchant. Lots of notes on all the little details, like making the original artwork on graph paper if you don't use CAD, getting the right etchant concentration, and using dental burs in a Dremel tool instead of drill bits.

I've used this method for about 20 years now. If you don't already use a CAD program, you may find the graph paper approach to be a _lot_ faster than learning the CAD, though you'll want to do that eventually. But I've used graph paper for fairly complicated

2-sided boards with good results.

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis Shareware from Interstellar Research

Get positive PCB, e.g. Kinsten stuff. Get transparencies for ink jet or laser printer (whichever you will use). Print the artwork you design onto the transparency. Transfer transparency onto the board using UV lights if you can get one or sun/normal light. I never used sun or normal light so I do not know what kind of exposure is needed. Remove the unexposed UV-sensitive layer with sodium carbonate (can be bought from supermarket here, used for foot baths, water softener, etc...). Etch with ammonium pesulphate or sodium persulphate or sodium/potassium hydroxide, heated. Use ferric chloride if you do not need to heat but it is very messy stuff, we never use it anymore. We use ammonnium persulphate, its clean. Need to have a ventilated room though. Remove the hardened protective material from the top of the tracks with metho/wood alcohol - leave the board in it for 5 mins and the stuff just falls off. Finish off by applying lacquer to the board - protects it from oxidation.

For design I can recommend Eagle - it has its quirky but it produces good artwork, has everything that expensive software has and it is very stable in my experience.

Don't cross-post, it is bad form.

Hi Jeff:

I have found that the prices for prototype PCB fabrication by commercial PCB houses is much cheaper than the time that I would have to spend to make them myself, even on a student's budget.

A student can get for $33 at

a double sided, solder masked, and silkscreened PCB.

Get Eagle which can do up to 100mm x 160mm for free, and your set.

Next, seriously work at getting someone at the school to pay for your costs. Get some sort of lab assistant job, or get involved with some research projects. There are likely folks who have budgets that can pay for your PCBs, and maybe even a higher license level of Eagle to do larger boards and more layers, if need be. Dream up some cool circuit they can use for an undergrad lab project, talk them into wanting it, then put your project's pattern on the same board (but try to make it unobvious, as 4pcb.com might reject it if it's obvious there are more than one "part numbers" on the board). Cut the two patterns apart later.

I would also avoid the real easy and simple PCB programs out there, which may not provide enough headroom for you to grow, as you move closer to a career. Eagle is a "mid-level" program. In my view, it's just right for a beginner, and sophisticated enough to handle your needs for many years of learning and skill development. Also, the newest version of Eagle really adds a bunch of features that take it closer to the high-mid-level. And there are a number of licensing levels for different budgets.

Good day!

--
_______________________________________________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA
crcarle@sandia.gov -- NOTE: Remove "BOGUS" from email address to reply.

Is that a student special? Their terms state a minimum of 3 pieces at that price, plus shipping, plus a $10 handling fee, so more like USD

120.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Yes.

Jan-Erik.

No.

Jan-Erik.

Are you feeling ambivalent about it, Jan? ;-)

It seems to be the most popular of the low-cost packages.

BTW (for Jan only), here are some drawings of those knobs I sent you.

Best regards, Spehro Pefhany

--
"it's the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Yes, sorta. But potent for the price.

The user interface is not quite intuitive, but once in "their" frame of mind it makes sense. Flexible, extensible, and the free version is full-featured with 2-layer support (licensed: 16 layers).

User discussions provide some good insight on what it can/can't do: news://news.cadsoft.de/eagle.userchat.eng news://news.cadsoft.de/eagle.support.eng

Probably the biggest shortcoming with the free version is the missing manual (not even in PDF), which comes only with licensed copies. You've got to get by with other docs, tutorials, and an advice website.

Non-commercial version: $125; full license: $1200 (if you want the auto-router)

[snip]

Anyone have comments about ExpressPCB?

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

(Okay, I'll cross-post this response. My other response, re Eagle, was posted only to sci.electronics.design.)

I've used this service several times over the last two years. They do very high quality work at reasonable prices; their minimum price ($62 including express shipping for three identical 2.3"x3.5" boards, double-sided) is the best I've found, and their prices for small quantity production (50 boards), with solder mask and silk screen, are pretty good too. The quality of the finished boards is as good as anything I've seen in any commercial product. At this price and turnaround speed, they can do boards more cheaply and quickly than I can do them myself, given that whenever I do it I have to buy new supplies and remember how to use them.

Their layout software is simple and somewhat limited but very easy and intuitive. Their schematic capture is not great, and the integration between the two is dubious. (Why, why, why

The biggest limitation is that they don't export Gerber and they don't usefully import netlists. So you're stuck using their software and their production service; there's no way to scale. You can't even print out camera-ready art to etch it yourself. Also, their layout software is not very smart about things like filled polygons, curves, and so forth.

Bottom line: they're great for very simple boards; but they don't scale well beyond that.

-walter

[snip]

I've been toying around trying to decide whether to PnP Blue something and try it myself, or just order from ExpressPCB. I'm developing a product idea which, in the end, if it works, I'd just have a commercial house lay it out. Right now I'm planning on building the system up in small pieces while I sort out the circuit details.

As for printing out ExpressPCB, it *can* be done. I took "unprintable" as a challenge and found a way to do it...

Here's the best way I've found so far:

(1) Print desired layer to a file using a *color* Postscript printer driver (I installed a Tektronix 780 Graphic printer in Win2K). (2) Bring into Paint Shop pro (at 300/inch) (3) "Posterize" the image (4) Using "Magic Wand" tool select one piece of trace (5) Selections > Modify > Select similar. This will select all instances of that color on the image. (6) You can then copy and past that selected content. (6a) You may need to "Resize" the image to make it actual size. (7) Save as desired file-type.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

[edit]

Those are some of the reasons I went with Eagle. I'm sure someone of Jim's stature could afford it. It would be wise not to get invested (time and $$$) in a dead end, capabilities-wise.

The new version of Eagle will do blind and buried vias, offset vias (keyholes), and curves, as well as major enhancements to the library management. There are lots of parameters for design rule checking, and it's taken me a couple years to finally figure out all the details and options it provides about polygons and supply layers. It is becoming quite a powerful program.

Good day!

--
_______________________________________________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA
crcarle@sandia.gov -- NOTE: Remove "BOGUS" from email address to reply.