Author Topic: KiCad thieving patterns?  (Read 2304 times)

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Offline bson

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KiCad thieving patterns?
« on: November 01, 2015, 10:04:16 pm »
I've noticed there's no option in KiCad (bzr 6202) for a fill zone to have a thieving pattern.  What's a good way to do this?  I mainly want it reduce board warpage and perhaps strain.  (Or more specifically, let the pattern help absorb up the strain from a large solid ground pour.)  Setting a suitable grid size and manually clicking pads onto the F.Cu layer only (no mask)?  If I do this, is there a way to easily hide them?  Is there some clever way of managing them, for example by creating a component with 100 pads, no connected or visible pins, and a footprint that ONLY consists of a checkerboard of unlocked and unmasked pads?  Then groups of pads could be moved around as needed.

Offline bson

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Re: KiCad thieving patterns?
« Reply #1 on: December 07, 2015, 07:10:23 am »
Just in case anyone is curious, I think I figured out a way to do this.
1. Create a footprint. Set the grid to 0.5mm.
2. Add a single rectangular pad.  Set its size to 1.5x1.5mm.
3. Set its solder mask clearance to -1.5mm.  This will make the solder mask cover it.  (-0.75 probably works too, or maybe a little more to allow for rounding error.)

To add a thieving pattern (in the OGL renderer, didn't try the software renderer):
1. Switch to a 0.5mm grid.
2. Place the covered pad footprint created above.
3. Place a few more one grid spacing apart (0.5mm)
4. In the OGL renderer, select a group of pads
5. Duplicate (cmd-d on OS X) and place the copy 0.5mm apart from the others
6. Duplicate and place more

Maybe create a few more handy pattern, but I found the manual fill pretty quick and easy when standardizing on a base grid size.  0.5mm grid with 1.5mm pads works nicely.

Still need to confirm this works reliably with a gerber viewer.  Will be using it on my next board to have significant bare space on the top layer.
« Last Edit: December 07, 2015, 07:12:11 am by bson »

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