Jack,

I seem to recall that hole size was originally specified in MIL-275 / IPC-275D as .006" - .028" (.15mm - .71mm) over max lead depending upon classification.

At my most recent previous gig we were using max lead + .017" for thru hole sizing based upon manufacturing trials with positive results. We used thru components only in special applications and the hole size worked well for both wave and select applications, thru components were hand inserted. Mfg volume was 1K to 100K per year.
> 
> From: DesignerCouncil automatic digest system <[log in to unmask]>
> Date: 2009/01/08 Thu AM 12:00:37 CST
> To: [log in to unmask]
> Subject: DesignerCouncil Digest - 6 Jan 2009 to 7 Jan 2009 (#2009-2)
> 
> 

Dave Schaefer
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