It depends on the tolerances you are manufacturing and inspecting.
Calipers are a fair all around tool, however, due to the large area of
the measuring surface, some averaging occurs.  Calipers are also only
good around the periphery of the board.  Comparators are a fine tool,
but rather expensive.  There are "deep Throat" micrometers with radiused
tips that are very effective in measuring the middle of boards.  It
really depends on your application.  I hope that some of these ideas
help you in your measuring concerns.

Darrell Bonzo
Quality Engineer

> -----Original Message-----
> From: Cobey Schmidt [SMTP:[log in to unmask]]
> Sent: Tuesday, June 09, 1998 4:02 PM
> To:   [log in to unmask]
> Subject:      [TN] Thickness Measurements
>
>                 Greetings all!
>
>                 I have a question.  (obviously)
>
>                 What are the best techniques and tools for measuring
> the
> thickness and other dimensional specifications on a PCB?
>
>                 Thanks! :-)
>
>                 Cobey Schmidt
>                 VisionTek
>                 1175 lakeside Drive
>                 Gurnee, IL 60031
>                 [log in to unmask]
> <mailto:[log in to unmask]>
>                 (847) 360-7566 voice
>                 (847) 360-7443 fax
>
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