I would add some to this suggestion... we use the double stick tape
     also primarily because it enables us to eliminate the component skew
     due to pushing the component onto the solder paste... however, also
     realize that many placement machines make placement adjustments
     depending on the lead verification algorithm if you are dealing with a
     gull wing leaded device for example... also note that it is highly
     likely that leads could be independently skewed 1 or 2 mils... another
     issue is the tolerance on the nominal dimension of the component as
     well as the error associated with the centroid of the component on the
     board at the programming level.... I would consider all of these
     'errors' when evaluating results... since we may be dealing with
     fractions of a mil, the density of your test board may be an issue in
     regards to the etching of the traces and their symmetry in respect to
     the top of the pad geometry....

     marcelo

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Subject: Re: [TECHNET] [Technet] Assy: Placement Machine Measurement
Author:  "TechNet Mail Forum." <[log in to unmask]> at smtp