Steve,

Thanks for your suggestions. One of the engineering techs had some modeling clay that worked fairly well.  I eventually was able to measure the height of the pedestal, standoffs and components and calculate what the gap is and compared that to what I empirically measured using putty.  The putty method yielded fairly good results but is very sensitive to operator technique. Measuring all of the pieces and then calculating the gap is probably the best approach.

Best Regards,
-Joe M.


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From: TechNet [mailto:[log in to unmask]] On Behalf Of Steven Creswick
Sent: Thursday, February 18, 2010 4:00 AM
To: [log in to unmask]
Subject: Re: [TN] Best way to measure "actual" themal pad compression

Joe,

Since you are likely to disallow use of Plastigauge, or similar products ... can you optically measure the delta between the top of the board and a known point on the component, thereby inferring the gap by subtraction - without dissassembly?  

Many quality microscopes have a calibrated vertical vernier that can be used for height measurement.

Will the compression pad show up under x-ray?  Could you ultimately go through the test pieces and math to equate volume to thickness [using Plastigauge]??

Steve C

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Joe Macko
Sent: Tuesday, February 16, 2010 3:34 PM
To: [log in to unmask]
Subject: [TN] Best way to measure "actual" themal pad compression




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