[Koogar] came up with a useful tool for checking the measurements of your layouts in Eagle CAD. He calls it the Gridrunner; a custom part that adds a 200mm ruler to your design. Tick marks are in 1/10th of a millimeter increments for great accuracy when used with the zoom feature of Eagle. Once you’ve got the layout just right, delete the ruler from your design and export it for fabrication. [Koogar] does mention that the beta version of Eagle 6 has a new measuring tool, but he still thinks the Gridrunner offers some things that the built-in tool doesn’t. See just how handy it is in the video after the break. The measuring starts about 1:40 into it.

We found it interesting that [Koogar] is using Eagle for quite a bit more than PCB design. We’ve used it for laying out a drilling template for face plates before, but he’s going far beyond that. He uses the library editor to recreate the parts of his CNC machine which he says are then really easy to align. From there, he exports the CAM files for mounting brackets. Do you use Eagle for something other than PCB design? Let us know about it by leaving a comment.

[Thanks Rupert]

[Karl] wrote in to tell us about a software package called EagleUp that will import your Eagle CAD PCB designs into Google SketchUp. It bridges the gap between the two using the open source image processing software ImageMagick.

As you can see above, you’ll end up with a beautifully rendered 3D model of your hardware. This is a wonderful way to make sure that your enclosure designs are going to work without needing to wait for the PCBs to arrive from the fab house. It is available for Windows, OSX and Linux (although the last time we tried to run Sketchup under Wine nothing good came of it — perhaps it’s time to try again).

In [Karl's] case, he’s working on an Arduino compatible board based around the Xmega. He mentions that EagleUp is a great way to get an idea of how component placement will end up, and to see if the silk screen layer is going to turn out well or not. Here’s a link to one of his test designs.

Version 6 of the popular schematic and PCB layout software EAGLE is now in beta testing. The most notable change is the migration to XML file formats that we looked at last month.

[PT] didn’t waste any time getting his hands on the software and giving it a thorough test drive. The image seen above shows the files of a MintyBoost. It’s impossible to make out at this resolution, but it is indeed spitting out human-readable (well maybe) XML in the windows below instead of the ‘no trespassing’ binaries they used to use.

Earlier today when working on a feature we had to jump on a different computer that had EAGLE installed in order to look at a .SCH file. We wonder if someone will put out a rendering package that can parse the new format and spit out a quick PNG? At the very least, we expect to see some useful hacks for part replacement or pin swapping. It shouldn’t be too hard to poke around and figure out what happens when changing some of the stored values. Got anything in mind that you can do by editing these by hand?

Oh, we almost forgot! The biggest benefit you get from this is the increased version control compatiblity since programs like git will be able to perform diff functions on the files.

Here is the next installment in our series of Eagle CAD videos. In this video we skip ahead a bit and show off the CAM processor that you use to create the files necessary to have your circuit boards be manufactured. After watching this video, you will know how create a new CAM program, load a circuit board into the CAM processor, tell it where to save your files, and actually use it to create the files.

We’re skipping ahead today because of a screw up on our part. We meant to show the layout portion of the program today but edited the wrong video… We’ll show layout next week. After that, we will show the completed circuit board and solder the parts onto it.

If you are itching for some Eagle CAD layout info, you may be interested in some supplementary videos that we have uploaded to our Youtube channel. In those videos, we show how to use the most important features in the layout portion of the Eagle CAD.

Have you missed the previous videos? Here are some links to them:

Schematic and the beginning of a custom part: [click here]
More custom part stuff: [click here]

Video is after the break:

We all know that Eagle has its share of shortcomings. Instructables user [westfw] was particularly annoyed by the fact that while Eagle keeps copies of up to 10 revisions of your board, it cannot open those files without resorting to manually renaming each one. Even more frustrating to him is the fact that you can’t use Eagle to view two files simultaneously in order to compare layouts. This made hunting down changes quite tedious, so he started looking for a better way to do things.

While using his favorite open-source gerber viewer gerbv, he noticed that the application let him load multiple copies of the same layer, XORing the PCBs’ colors together. Realizing that with some clever color selection, he could use gerbv to automatically highlight layout differences, he set off to automate the process.

The resulting script works on any flavor of *nix, and should play nice in Windows under cygwin as well. The script reads through Eagle backup files, renaming them and tweaking the colors so that when XORed, they show up as bright red areas in gerbv. It’s a simple yet handy tool to have on hand if you happen to do a lot of PCB design.

Up to this point we’ve used Eagle CAD as our exclusive PCB design and schematic layout tool. But [Brian] has inspired us to try something different thanks to his KiCAD tutorial.

KiCAD is an open source printed circuit board design tool. Since we like to rock the Linux here at Hackaday getting our hands on this was as easy as:

 sudo apt-get install kicad

The version in the Ubuntu 10.04 repositories is a bit older but seemed to work just fine. [Brian] jumps right in with one of our most dreaded tasks on Eagle, designing your own parts. He knows of a nice online tool for automatic KiCAD part generation and walks through the process of building a voltage regulator and importing it for use in your own personal library From there it’s off to layout a power supply schematic for a breadboard PSU. The lesson continues with board layer, as well as the process used for exporting data for PCB fab house. We think this tutorial works well if you’re already familiar with PCB layout using a different software package but it moves a bit fast if this is your first time.

KiCAD seems like a nice tool and we’ve heard from many advocates in the comments over the years. Look for our next PCB design to be on KiCAD as we just need to use it for a while before passing judgement.

[PT] posted about an exciting development from Cadsoft, the migration to XML based parts, schematics, and board layouts. The adoption of this open standard goes hand-in-hand with the open hardware initiatives people like [PT] have been pushing for.

Cadsoft Eagle is our go-to schematic and PCB software. We even have a tutorial which guides you through preparing your files for PCB manufacture. But the files containing parts libraries, schematics, and board layouts have always been binaries. A transition to XML means a lot of things. They will be easier to edit, and much friendlier for tracking changes using version control systems like SVN, CVS, Mercurial SCM, Git, etc. But immediately on our minds is the accessibility for hacking. Think of how easy XML parsing is in programs like Python. It should be snap to write scripts on a whim that will manipulate the XML files in any way imaginable. This doesn’t discount the value of Eagle, it extends the usability far beyond what any team of engineers at Cadsoft could produce by themselves. And for that, we say Bravo.

[Sebastian] made a 3D mouse work with Eagle CAD. He was inspired after using a 3DConnexion device to manipulate the views in a copy of Solid Edge 3D CAD modeling software. The system uses the 3D mouse in one hand with the regular mouse in the other.

It turns out that 3DConnecxion offers a lot of tools to get their devices working with your software. [Sebastian] downloaded the .NET example and modified it to read in data from the device. With the use of hot-keys he manages to get zoom, pan, and centering to work (see for yourself after the break). The only drawback to his implementation is that he can’t pan while dragging parts. But that’s just a small issue waiting for you to find a solution.

[Colin] has cut his teeth with about fifteen PCB orders. He wrote a tutorial describing the process and sharing his tips on avoiding common problems. You may remember our own How-To prepare designs for manufacture early last year. In that post, [Ian] shared his veteran knowledge by outlining BatchPCB’s board design process. This time, [Colin] is using Advanced Circuits in Colorado as a board house, giving us more insight on how the different companies work. No matter who you choose for manufacturing, make sure you really understand how to properly format and troubleshoot your designs. It’ll end up saving you a lot of time and money.

[Jeff] set up version control for Eagle libraries and projects. He mentions that Eagle has become the standard for open source hardware projects and he’s absolutely right. We use it for our projects, and we’ve grown to expect that the posts we feature have Eagle files available in most cases.

But Eagle falls short in its library management. There is some amazing work from SparkFun to support a usable parts library, but who hasn’t added parts themselves? [Jeff] setup libraries using github so that changes and additions to the libraries can benefit all and cut the amount of time spent making custom footprints for new components and packages.

Ruin & Wesen are a two person shop creating specialized music gear. As part of their recent MIDI Command development, they got into case manufacturing. They purchased a mini CNC mill to cut the aluminum cases. Unhappy with the software options provide [Wesen] decided to write his own G-code generator. G-code is part of the numerical control used to command CNC machines. He implemented his interpreter using the language he’s most familiar with: Common Lisp (not surprising if you notice the website’s backend). The post covers the design philosophy used and some of the problems that came up. We look forward to future releases since the interpreter can generate milling code using processing.org sketches and cut PCBs directly from Eagle.

You may remember Ruin & Wesen from when they shared their Eagle layout videos.

[Thanks fbz]

Cadsoft Eagle is a multi-platform freeware circuit layout program. Lots of open source hardware is designed in Eagle, and it’s become a hobbyist favorite. We use it for all of our hardware designs.

There are several ways to turn an Eagle design into an actual printed circuit board (PCB). We’ll show you how to save Eagle designs as industry-standard gerber files that are accepted by any PCB manufacturer. You can use the gerbers to order a single prototype, or a full panel.

Introduction

Toner transfer is the beginners’ favorite way to make a PCB because the investment in materials is minimal. We’ve covered toner transfer before. Most PCBs in our how-tos are made with the photo-resist process.  The photo process makes nice boards, but requires a bit of equipment; sensitized boards, developer, and an ultra-violet light source.

Some board manufacturers, like Olimex, make PCBs directly from Eagle .brd files. Most require a minimum order of one eurocard-sized PCB (100mmx160mm). Good if you need a few boards, expensive for a single experimental prototype.

The cheapest option is to submit gerber files like the professionals. Any PCB manufacturer will accept gerber formatted design files. Gold Pheonix sells 155square inches of PCB panel for $110. If you’re looking for something smaller, services like BatchPCB and PCB-Pool combine small orders and submit them as a full panel. Either way, you’ll submit gerber files to the board house. This is the process we describe.

Process overview

• Prepare the design.
• Create gerbers, generic files accepted by any PCB fab house.
• Verify that the gerbers are correct.
• Send the design for production.

Prepare the design

We’re going to walk you through the process of preparing our digital picture frame PCB for production. This design requires a double-sided board with fairly small traces.

Download the project archive (ZIP) from last week. Open the .brd file with the freeware version of Cadsoft Eagle.

The ground fill is empty when the file opens. Press the ratsnest button (or Tools->Ratsnest) to fill in the empty polygons.

Board manufacturers publish specifications outlining their production capabilities, such as the smallest possible traces, spacing, and drill size. BatchPCB has 8mil minimum traces and spacing, and 20mil minimum holes.

Don’t torture the manufacturer. Just because they advertise 8mils, doesn’t mean it’s safe to make every trace 8mils. Slightly larger-than-minimum tolerances will reduce manufacturing errors. The digital picture frame has 8mil traces around the tiny LCD connector, shown above. The traces are 8mils only until there’s enough clearance to use 10mil traces.

Use Eagle’s design rule check to make sure your board doesn’t exceed the manufacturer’s production abilities. Download the SparkFun design rules (DRU) for BatchPCB, or the Olimex 8mil (DRU) or 10mil (DRU) design rules.  Click the DRC icon (or, Tools->DRC) and load the design rule file. Eagle analyzes the design and highlights any areas that violate the design rule parameters.

Correct any errors. Here, the spacing between traces is too close. Sometimes the spacing on a part footprint is too small to be manufactured. Sparkfun’s default footprint for the  Nokia LCD connector had pad spacing less than 8mils. We edited the part library to make the pads smaller, and the separation larger.

It’s helpful to include part numbers on the printed silkscreen layer. BatchPCB prints a silkscreen on both sides. Be sure to see what your board house offers, some charge extra. Use the smash tool to unlink obscured labels, then move them to a better location.

Create gerber files

Gerber files are the PDFs of PCBs. Gerber files describe a PCB exactly as it should appear, agnostic of the display hardware. It’s a final production format that isn’t intended to be edited. We created our gerber files in Eagle using the procedure outlined in SparkFun’s Eagle tutorial.

The Eagle CAM processor writes gerber files, open it from the menu under File->CAM processor.

SparkFun has a script (CAM) that configures the CAM processor to make gerber files. Load the CAM script using File->Open->Job…

By default, SparkFun’s silkscreen configuration only includes the place layer. Our parts usually have labels on the names and docu layers, activate these layers on the top and bottom silkscreen tabs to add them to the output.

Click Process Job to create the gerber files.

The CAM processor creates seven files that we need.

• Top and bottom copper (.GTL, .GBL)
• Top and bottom solder mask (.GTS, .GBS)
• Top and bottom silkscreen (.GTO, .GBO)
• Drill file, 2.4 leading (.TXT)

Verify that the gerbers are correct

Verify the CAM output in a gerber viewer to make sure everything was positioned correctly. We followed SparkFun’s suggestion and used Viewplot.

Load the seven files with Viewplot. Be sure to specify the drill file type as 2.4 leading.

Check for errant vias, mirrored layers, and alignment. We’ve noticed that text added to the silkscreen layer is usually bigger than it was in Eagle. Correct any problems and run the CAM processor again.

When everything looks good, the board is ready for production.

Send the design for production

Zip the seven gerber files and submit them to the PCB fab house. Remember to tell them that the drill file format is 2.4 leading.

BatchPCB is a pooled panel service that sells space by the square inch. Other manufacturers and batch services require you to order at least a full eurocard. We use BatchPCB for prototyping because we never need the extra board space of a full eurocard, and we don’t mind the average 20day wait.

At BatchPCB, $2.50/square inch buys a PCB with silkscreen on both sides, unlimited vias, and a huge range of drill sizes; stuff that usually costs extra. BatchPCB’s minimum traces, spacing, and drill are similar to other prototyping services. There’s a $10 per order setup fee, but an order can include multiple designs. Shipping, even internationally, isn’t outrageous.

If you need a lot of the same board, look at Gold Phoenix. They manufacture boards for BatchPCB. A 100 square inch panel is $100, a 155 square inch panel is $110.

Create an account at BatchPCB. Click upload to add a new design. Name the design and upload the zip archive containing the 7 gerber files.

Verify that the gerber layers were successfully detected.

Verify that the correct size was detected.

The BatchPCB rule check ‘robot’ will verify that your design meets production standards, and send an e-mail in a few minutes. Since we ran our own rule check prior to sending the design, we can expect that everything will be fine. Click continue and you’ll have the option to order the board. For more help, see the BatchPCB help and support forum.

Receive your boards

Boards arrive from BatchPCB in about 20 days. Check the boards for obvious errors before soldering. Some manufacturers test PCBs, BatchPCB doesn’t. We’ve ordered PCBs from two of the popular hobbyist board houses, Olimex and BatchPCB, and all the boards have been satisfactory.

Taking it further

It’s easy to order professional PCBs using gerber files. Why not build that awesome DIY project you’ve been putting off?

What has been your experience with PCB fab houses?

UPDATE: the files have been moved! find them here.

[Garrett] from macetech has been prototyping shields for the Arduino development platform. Arduino’s have an inexplicable nonstandard spacing between two of the banks of output pins. This means that you can’t use regular perfboard with them. To make the design process quicker, [Garrett] has put together an Eagle file that just includes the male header pins. The file also has a line indicating the tall lower board components so you can avoid creating shorts.

SparkFun has posted an excellent guide to the many different issues you could run into when you finally decide to get a circuit board professionally produced. We assume that most of you aren’t running a professional design firm and will appreciate these tips gleaned from years of experience. They provided a rule list, Eagle DRC, and CAM file to help you get it right the first time. The end goal is designing a board that won’t be prone to manufacturing errors. The tutorial starts by covering trace width and spacing. They recommend avoiding anything less than 10mil traces with 10mil spacing. For planes, they increase the isolation to 12mil to avoid the planes pouring onto a trace. They also talk about annular rings, tenting, labeling, and generating the appropriate gerber and drill files. SparkFun isn’t completely infallible though, and manages to produce a coaster from time to time.

SparkFun naturally followed up this strict tutorial with a guide to unorthodox header hole placement. If you want to learn more about Eagle, have a look at [Ian]‘s overview of Eagle 5 and Ruin & Wesen’s layout videos.