In this post I’m going to explain how to output files from Eagle PCB in order to send your designs off to be professionally fabbed. There are two major steps before this in the process: creating the electrical schematic, and moving from that schematic to a board layout. I’m not going to cover those at the moment, as they were the subject of a recent ITP drive-by, and the impetus for this post was to add the production info into the mix, but if there’s any demand I’ll post some more tutorials down the line. In the meantime, if you haven’t moved from schematic to layout yet, Instructables has a couple of excellent tutorials on PCB layout in Eagle and also making custom parts in Eagle.

So, from here on out, I’ll assume you’ve got a finished schematic and layout, and are ready to send it off for production.

First, you have to output your files to send to the production facility. The CAM processor in Eagle takes your PCB layout and breaks it down into things that the fabrication machines can use, in the form of copper, paste, silkscreen, soldermasks, and drill files. You’ll have multiple of each type, except for the drill file. These are sometimes called Gerber files, in reference to a popular manufacturer, and are what the production facility will need to make your boards.

I’ve uploaded some output presets which will produce the files you need for most production facilities (Gerber274x with Excellon drill files). You can download those here (Eagle CAM presets), and drop them into your /Eagle/cam/ folder. These presets are designed for two layer (top/bottom) output, but if you’re doing something more complex than that, you probably won’t be reading this! Okay, now we’re ready to output!

Click the CAM button in the toolbar (it looks like two teal filmstrips).
Go to File->Open->Job…
Select sfe-gerb274x.cam first.
Click Process Job, and you’ll see a number of progress bars race by as Eagle does its work.

You may have noticed that we output an Excellon drill file as part of that job, but, for some reason, due to a quirk of Eagle, it never outputs correctly for me as part of that job preset. So, let’s output just the drill file in the correct format.

In the CAM processor still,
Go to File->Open->Job…
Select excellon.cam.
Click Process Job, and you’ll have the correct drill data.

Now, if you look in your project’s folder (which should be somewhere like ~/Documents/eagle/projectname/), you’ll see a number of new files. These are your CAM files which you’ll send out for production. You should have:

• *.DRD - drill data
• *.GBL - bottom copper
• *.GBO - bottom silkscreen
• *.GBS - bottom soldermask
• *.GTL - top copper
• *.GTO - top silkscreen
• *.GTP - paste
• *.GTS - top soldermask

The awesome thing about designing PCBs is that Eagle (and other CAD software) will actually produce the files that control the fabrication machines. On one hand, this gives you total control over what gets produced. On the other hand, if something doesn’t turn out right, you only have yourself to blame, so you want to double check everything before confirming any order.

Now that you’ve got your files, zip them up, and upload them to FreeDFM for checking. No matter who you wind up ordering boards from, FreeDFM is a great service to use. Within an hour (often less), you’ll receive an email that will point out any obvious problems with your files and layout, as well as giving you a link to view your plots online. This lets you double check the layout of each part of the board, and makes it easy to spot errors or problem areas. If things aren’t correct (and they hardly ever are, the first time, fix them, output, and upload again. Just be sure you change the version number, as otherwise their system may not recognize it as a new upload.

FreeDFM is owned by Advanced Circuits, so you’ll also get a quote from them along with your results. The quotes page is wonderful in that you can see how different quantities and turnaround times affect your order. (And, yes, unless you know better, you’re fine with prototype quality boards and not paying for the electrical check.) They produce their boards in Colorado, so can turn things around in a day if you’re willing to pay exorbitant fees. When we ordered boards for Socialbomb, we ended up paying $500 for 50 boards with a 2 day turnaround. In general, things get cheaper for larger orders and longer turnaround times. For Advanced Circuits, if you leave two weeks for production, you’ll probably even be able to get small quantities cheaply. And, I must add, they have excellent customer service, and are very easy to get ahold of on the phone. After my wonderful experience with Advanced Circuits, though, and seeing that even the Socialbomb boards would have fallen to under $4 a piece if we had a few weeks for production, I don’t feel the need to shop around. Other people at ITP swear by BatchPCB and Golden Phoenix, which both produce the same quality of boards at a discounted price. They both send the boards to China for manufacturing, though, so you really need several weeks turnaround time, but you can get some simple boards down to a few dollars a piece in quantity.

Having your PCBs manufactured for you is very rewarding. I highly recommend it over perf boards or even etching when you’re ready to take your projects to a second revision.

Update:Advanced Circuits also has a fast and cheap board fabbing service called BareBonesPCB, which I wasn’t aware of at the time (probably because it’s hidden under a different domain name!). It will probably do the trick for most projects, and still ships in a day. Woot!