My first Eagle Cad Project

[kevilay]

Hey guys Im doing my first guitar pedal PCB board in eagle cad. Im new to the program and have been watching some videos. I got some boards setup but I do have a few questions. What size traces and holes should I be using for guitar pedal applications. On another note, there are so many different resistor, capacitor and diode maps. What ones should I be using for regular size components? Is it common to have two layers for guitar pedal boards? Is there a way to print the layout out in realsize so i can check to makesure everything is sized properly?

Thanks
Kevin

[kevilay]

forgot to mention. should I be using a ground plane as a second layer to help with noise?

[ringworm]

Most of those points are dependent on the size of the board and the circuit.
I have my projects set to milimetres and use anything from 0.6 - 1 for traces depending on available space. I also use the restring function to set my pads to '22'. I make all my boards as single layer projects and have never made a double layer board, better to keep it that way for simple effects if your just figuring it out. You don't always need a ground plane either but it can't hurt to figure out how to do it.
File>Export>Image will get you your pcb, which will automatically be the correct size for the parts you have selected, raise the print resolution to 300dpi or something though. Select monochrome for making your press'n'peel transfer. it will also automatically be reversed for printing. No need to flip it in a graphics program.
Check out gaussmarkov's tutorials, they are specifically for pedal building and are really good http://gaussmarkov.net/wordpress/tools/software/eagle-cad/ and download his library files as he has collected a lot of useful parts for pedal building in the one folder.
 

[kevilay]

that image didnt show up, could you relink it please?

[ringworm]

Sorry, what image? The link takes you to the eagle-cad tutorials on gaussmarkov.net. I just checked it and it still works.

[JRB]

It's always good practise to make a ground plane it prevents EMC problems and saves time when making the pcb since less copper has to be removed, at least that's what my teachers told me.
To make one first name your ground tracks GND with the properties command (the big I at the top of your toolbar).
Then create a polygon around your board with the polygon tool (the rectangle with the missing corner).
Then type Name in the command bar and press enter.
You select the polygon you just created and change its name to GND. The ground tracks are now connected to the polygon.
Now go into the properties of the polygon and change the isolate value to how much room you need between the ground plane and the tracks, I use 1mm myself.
Last thing is to press Ratnest(the green cross with the circles at the legs) and you're done.

[DavenPaget]

Using a double sided board with a ground plane on the underside usually leads to the sudden craze for SMD .
Or you could use a double sided board and plate only the holes that are on the top layer , as in , plate only the holes that need to be connected to the top plane .
OKAY , i haven't made a PCB but that's what i learnt from Dave L. Jones of EEVBlog

[kevilay]

what about the boards that you have made professionally. What are they normally? Its like a buck a square inch. The green boards with the silkscreen on them, all predrilled.

[DavenPaget]

what about the boards that you have made professionally. What are they normally? Its like a buck a square inch. The green boards with the silkscreen on them, all predrilled.

They are good stuff , hasn't made one professionally but EEVBlog on youtube can help you .

[_dB]

The gaussmarkov library is awesome but a word of caution: the pads and drill sizes on most of the components are very small (too small for .22 gauge stranded wire, for instance). You might want to google for Madbean's version which IMO is more usable (sorry can't be bothered to get a link, but it's easy to find!)
   
There's nothing wrong with double layer boards, if you are going to have them fabricated. Having two layers will make routing much easier in some cases. Try to route everything except ground on the top layer. Then your bottom layer just becomes a large ground plane.

Also don't be afraid to use the autorouter. I usually like to place components, autoroute to see where the traces go, then move components to optimize the routing. In the end you can manually route everything but the autoroute steps make it a lot quicker to try different parts layout.

If you plan to etch your own, then that's another story.. stick to single layer in that case.

[kevilay]

Do I need to buy eagle to use the auto router?

[ringworm]

No, it works on the free version but does not do a very 'smart' job of it.

[egasimus]

Buy software? Who does that?

[kevilay]

Lol ill play around with it. I thought I needed a paid version for auto router

Thanks