Circuit Board Pad Layout

[mosfit]

What are the possible manufacturing issues and drawbacks involved in using a pad layout that is exactly the same dimensions as the maximum tolerance of the footprint of the device being installed?  Can I get away with having a 7% overhang of the interior "heel" of the surface mount part relative to the pad?  Why should I follow an IPC recomended pad layout that takes up so much of my board space when the device will fit snug on a smaller layout?

 

[wzkbrown]

1] there is no solder under the lead,&nbsp;&nbsp;The only thing to connect is the pressure of the lead on the pad.&nbsp;&nbsp;The electrical connection is through the solder fillet. The only thing holding the IC to the board is the solder fillet.<br>2] There is no way to inspect the solder joint for quality if it is all under the IC and you can't see it.<br>3] IPC gives guidelines for general production use. You should check with your production house on the minimum rules they need.<br><br>If you wish to hand build, inspect and test almost anything is OK, just don't try to sell it or support it as a product.<br>