With certain components, I’m getting errors in the DRC about pad sizes conflicting with mimum clearances. eg TO92 transistors.
I realise that I could edit the footprint to move the holes futher apart and spread the legs on the transistor, but is there anything inherantly wrong with ovalising the pads to fix the problem?
(FWIW I’m planning on CNCing my own boards, so need to set the pad clearances according to the endmill.)
What do you mean with “ovalizing the pads”?
KiCad has a whole bunch of footprints for TO-92 in it’s default libraries, and some of them already have oval pads.
And there are also some with their pads moved further apart from each other. TO-92 has long legs and you have a lot of room to place pads. You can easily put enough room between the pads to route a track in between the pads and still be able to insert the pins.
I merely mentioned TO92 as an example and my question was more about the principal of ovalising pads if a standard footprint has square or circular pads.
Smaller annular rings on pads leave more room for routing.
Bigger pads make hand soldering easier, but it does not matter much for wave soldering. Oval pads are a good option for DIP packages and such. They allow for easy hand soldering while still having a bigger clearance between the pins. Both for routing tracks and for (GND) zones to connect to itself in between pads.
FYI Most likely you’ve figured out how to set the Pads and Holes in a Bulk way that minimizes the work. But, one thing to consider is using good PCB CNC software to help tweak/set the Pads and Holes without needing to go back-and-forth from Kicad to CNC software.
I use CopperCAM for generating the Gcode - it has excellent Pad tweaking - baiscally a One-Click deal for Bulk and/or individual Pads…
Though a Windows Program, I run it on a Mac using PlayOnMac (there’s a PlayOnLinux, too).
I imagine there a plenty of YouTube videos for CopperCAM - this is my video but it’s only a preview to get a user going. It does not demo Pad/Holes so, below shows screenshot panel…
Thanks all.
@BlackCoffee I may come back to you with more questions - you seem to be the CNC guru!
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