I'm designing a PCB at the moment which will have a space for a Arduino Nano to plug in. On the main board I have got the outline of the Arduino drawn on the 'dimension' layer. I have nearly finished so I added a polygon for a ground plane, but the plain avoids the dimension layer? Is there a way to over ride this?
The top line of the inner rectangle was changed to layer 21 (top place). The other lines are dimension. I have used the dimension layer to get a "cuts to" border and never gave much thought to whether the pour included it or not. The little unfilled space up to it was an advantage for me.
For a quick fix, show the dimension layer, highlight it, then change it to something else (like top place) and re-run the ratsnest. You can change layers easily with the information icon or just use the change (wrench icon) dialog.
Hmmm I also get the issue of ground plains not running up to the edges of my boards (again drawn on the dimension layer). I'm not sure what I could do about that because I need to keep it on a layer that I print out (I'm going to etch my own), so I cant really change that onto layer 21 as well?
In a strange way, that is why I use the Dimension layer set to zero width to outline my boards. I also etch my own and like the small space as a trim line.
You could make your outline a signal (gnd), and it will fill completely to it.
Actually the dimension layer denotes the dimensions of the board. You should not use it for other purposes, use the mentioned t_place insted which should be used for silk screen or t_docu for other documentation. The fact that your ground plane keeps a set distance from the dimension layer is a feature, not a bug. This is most important on multilayer boards, where if you had all planes going to the very edge and milled or broke out the board out, there is a high chance that different layers will get shorted together.