Hello Ray,


>Can you tell me on what page of IPC-2221/2222 the fabrication allowance
>appears on?  I do not have a copy, yet, but the people I have asked to
check
>say it is not in there.  I have IPC-D-275, which has it in Table 5-10 on
>page 64.


IPC 2221
Table 9-1  Minimum Standard Fabrication Allowance for Interconnection Lands
at page 70

Level A  0.4 mm
Level B  0.25 mm
Level C 0.2 mm

Notes :
1- For copper weights greater than 1oz/sq.ft, add 0.05 mm minimum to the
fabrication allowance for each additional oz/sq.ft. of copper used.
2 - For more than 8 layers add 0.05 mm
3 - See 1.6.3 for definition of Levels A, B and C. (Producibility Level)
      Level A  General Design Complexity - Preferred
      Level B  Moderate Design Complexity - Standard
      Level C High Design Complexity - Reduced

I hope this helps.
Paulo Egon