Oliver, I've used the chart from this Mentor app note:
[1]http://www.mentor.com/resources/appnotes/upload/through-hole-padstac ks.pdf The terminology is a little different, but basically it recommends that for your 0.5 mm hole, you should have an 0.7 mm finished hole size (that's the "drill" parameter in PCB's pin definition, assuming your PCB house accepts finished hole sizes -- most do), a 1.2 mm "thickness", a 1.2 mm "mask", and an 0.3 mm "clearance". The last comes from the 1.5 mm "plane anti-pad" Mentor recommends minus the 1.2 mm thickness. Sometimes I want to tweak these numbers for a particular purpose, in particular to make the thickness and mask a bit bigger for hand soldering or just the mask bigger if I have doubts about the PCB house's registration abilities, but the app note numbers make a decent starting point. Stephen References 1. http://www.mentor.com/resources/appnotes/upload/through-hole-padstacks.pdf
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