Chuck wrote to us with a short tutorial on a simpler way to make footprints in Cadsoft Eagle. See our tutorial here.
Hello, my name is Chuck and I’ve been following your site for several months now. I was reading through the Eagle “How to make parts” tutorial and noticed you guys are making the pad layout far more laborious than it needs to be. Here’s how I layout pads:
Find the horizontal distance between pad centers and set the grid size to that number (0.5mm for your example). If you have 5 pins per side, as in your example, start two increments to the left of origin, then place 5 pads, one on each intersection. This should give you pads 1-5 laid out correctly.
Now, find the vertical distance between pad centers and set the grid to half of that (4.8mm in your example, so set it to 2.4mm). This is where Eagle’s functionality comes in very handy. Use the “Move” command and click on each pad. Move it straight down. It should snap not to the closest intersection, but to 2.4mm below its current position. Eagle parts snap relative to their original position; they do not snap to grid points unless you are placing it for the first time (and they thus have nothing to snap to).
Use the “Copy” command, starting on the rightmost pad and working your way left. Copy a pad, then move your cursor straight up. The new pad should first snap to the y=0 line, then should snap to the y=2.4mm line. Again, it moves it up 2.4mm, but not to the intersection points!
If you laid out the pads originally left to right, then the copies right to left, you should have 1-5 on the bottom then 10-6 on the top. Everything should be laid out exactly. All you had to do was divide one number by two to find the vertical spacing.
If you have an even number of pins, just set the horizontal grid to half the distance between the pads and offset them to position the origin between the two middle pads.
Hope this helps!
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