SparkFun Forums 

Where electronics enthusiasts find answers.

Questions relating to designing PCBs
By mrjimbo
#129914
Does anyone know which layer I should be using to show that I want a big rectangular hole in my PCB design?

I basically have large capacitors on a tiny PCB, so I want to put those two capacitors on their side inside this hole, so that only half of their dimensions for protruding from the top and bottom planes.

Thanks!
By rrpilot
#129948
All of them just like you would any other hole. The only time you would have a hole on select layers would be blind or buried vias.
By NleahciM
#130069
rrpilot wrote:All of them just like you would any other hole. The only time you would have a hole on select layers would be blind or buried vias.
That isn't exactly true.

He wants a rectangular hole. And he probably wants it not to be plated. This would typically be on it's own layer, or on the same layer as the board outline. I would ask the fab myself, as different ones have their own preferences.
Last edited by NleahciM on Tue Jul 12, 2011 9:07 pm, edited 1 time in total.
By mrjimbo
#130072
That isn't exactly true.

He wants a rectangular hole. And he probably wants it not to be plated.
You are exactly correct. After trying to Google for something I couldn't find the exact words to, I finally found the defining term - "cutout".

So, if you want to place a cutout on your PCB for the fab to cut away, as in a rectangular hole for my capacitors to suspend within, just outline the cutout area with the Dimension layer. Then, as mentioned above, a good label within this area would further communicate the cut away intention.

Another reason I was looking for a specific layer to use was because I needed EAGLE to understand that it needed to avoid this cutout area. I tried the Milling layer, but when I autorouted, EAGLE put traces all over this area. However, the Dimension layer forced EAGLE to avoid this region.