Hi Estcly, I would like to understand your question a little better. A) Can you tell us: Are the pad sizes wrong in: 1) the library; 2) the Gerbers; or 3) the PDFs? B) Is it the pad sizes that are wrong or is it the whole footprint is too big or too small (is there is a mistake in a scale factor)? C) Sorry but I do not understand what your dimensions refer to: `0.80.9` and `0.50.2`. Can you draw a sketch like the one below to show what you mean? 嗨Estcly, 我想了解你的问题好一点。 A）你能告诉我们： 是焊盘尺寸错误的： 1）库; 2）Gerber文件; 要么 3）PDF文件？ B）是它的焊盘尺寸是错误的或者是整个占用过大或过小（是有错的比例因子）？ C）很抱歉，但我不明白你的尺寸是指：`0.80.9`和`0.50.2`。 你可以画这样的素描： ![enter image description here][1] 展现你的意思？ [1]: /editor/20160210/56bafc13981f7.png

Sorry for not describing the problem clearly. I think the PCB footprint in the library is different from that offered by the manufacturer's PDF. For example, C0402, A=0.5mm, B=0.2mm, but in your surface mount library X=0.8mm, Y=0.9mm. This is only one example, I think there are some more problems for other devices.

OK got it now thanks. Dillon may be able to explain more about how the pads sizes were chosen for the **General Packages > Surface Mount > R0402 and similar packages.** I think they may have been chosen to make it easy to hand solder the parts. If you need specific footprints for reflow or for wave soldering then you would be best making your own either to the manufacturers' recommendations or to the IPC recommendations. 好了，现在的感谢。 狄龙或许能够解释更多关于如何垫的尺寸被选为[一般套餐>表面贴装> R0402和类似的套餐。** 我认为他们可能已经选择了可以很容易地手工焊接的部分。 如果您需要特定的脚印回流焊或波峰焊那么你最好让自己无论对制造商的建议或对IPC的建议。 p.s. Do these Google Chinese translations actually make sense or are they just rubbish? ***: )***