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How can I create a hatched pattern in a copper pour?

The following is extracted from the forum with the contributors name acknowledged.

While there isn't an automatic pour method, there is nothing preventing you from drawing a grid of traces yourself.

Do your other layout (touchpads, interconnect, other circuitry) first. Then:

Make sure "Allow Duplicate Tracks" is checked under Adding PCB Tracks in the Interaction tab of theSettings Preferences dialog.
Set Settings Grids Working Grid to the desired grid spacing (for example, 100 mils). Set the Snap Mode to Grid, Half Grid, or Quarter Grid, depending on you close you want to the touch pads or other components with the hatching. (If you use Half Grid or Quarter Grid, you'll want to set the Screen Grid to Visible since you will want to keep all the hatch lines on the grid. (The half or quarter grid just lets you extend the ends of the hatch lines to less than a full grid division to get closer to the touchpads and other components.) 

Then select trace tool. For 25% coverage, set the trace width to 0.134 times the grid spacing. (You could name the trace style, if you want - for example, Ground Hatch.) Then draw traces along the grid lines horizontally and vertically to create the cross hatching. Start at a component pin or via that is connected to ground, so the trace gets assigned to the ground net. Drawing the lines goes quite quickly, since the lines will be snapping to the grid. If you want, add a trace around the outside of the region you are hatching, connecting it to the endpoints of the hatch lines.

You can use thinner or wider traces to vary the percent coverage coverage. If the trace width is w and the grid spacing is g, the % coverage will be 100 * (2 * (w g) - (w g)^2).
Coverage percentage will be13.4 mil on a 100 mil grid gives 25%. 6.2 mil give about 12% coverage. 20 mil gives about 36% coverage.
The app notes I read suggest between 10% and 40% coverage for the cap sensing ground plane, depending on sensitivity and noise rejection needs.

-Brad

 

You can manually create a hatched copper area as below:

Set the grid and snap to grid for the horizontal pitch.

Select "Add Open Shape" and change this to the layer you require and the style for the copper width.

Just start placing the copper. It's obviously not as convenient as an auto fill, but it's quite quick with the snap to grid set.

-Boss

Of course, if placing the hatching diagonally (as in the posting by Boss), you would use a Grid setting in DesignSpark PCB of the square root of two (1.414) times the desired spacing between parallel hatch lines, measured perpendicular to the hatch lines. So for the 100 mil hatch spacing and 13.4 mil line width for 25% coverage I gave in my previous post, you would use a X Y grid settings of 141.4 mil in DesignSpark PCB (but still set the trace width at 13.4 mil).

-Brad

 

I have stumbled upon an idea which could take the pain out of making hatch-type copper pour & make the process almost as fast solid copper pour once the Hatch Pattern Template is made (as described below).

1. Make the Hatch Pattern Template: Units mil, Grid 50. Make a small Copper Pour area of 50mil x 50mil, copper width 1. Make this Pour Keepout. Copy this square & paste such that there's 5mil gap between the squares. You now have two 50mil x 50mil squares. Now copy both these (using right-click, Frame Select) & paste so that you have four squares. Likewise, copy these successively to make a 3" x 3" pattern, comprising about 3025 squares. Now select all these and group them (using right-click, Group). Your Hatch Template is ready to be used on any work PCB requiring it. Copy it.

  1. On your work PCB, make a Copper Pour area where you would like to have the hatch pattern.
  2. Paste the Hatch Template on your work PCB.
  3. Pour Copper on your work PCB.
  4. Delete the Hatch Template from your work PCB.
 
 
Hope this helps.
Sanjeev

 

 

 

 

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