http://www.dfrsolutions.com/hubfs/DfR_Solutions_Website/Resources- 
Archived/White-Papers/Reliability/Non-Functional-Pads-Should-they- 
Stay-or-Should-they-Go.pdf

On Feb 27, 2018, at 12:36 PM, Decker, Scott UTAS wrote:

> I agree with Richard. I was a firm believer in keeping them to  
> protect the via barrels from cracking, so no  way was I going to do  
> it. Then there was a study done many years ago, (I don't remember  
> who did it) that showed that only for very thick boards, like .120"  
> or more, was there any benefit to leaving them in. That benefit was  
> very small and it was not as much as you get from the Fabricator  
> and such, for the extra space you got... That said, we pull them on  
> all of our boards and we do class 3's all the time. One additional  
> thing I just thought of. In the past I used a lot, (ok almost  
> exclusively polyimide boards) and I believe that was where the  
> benefit was a good one, but I don't remember now for sure since we  
> don't use Polyimide here. :-]
>
>
> Scott Decker – Staff Engineer, PCB Design Services CID+ –  
> Electronic Systems Center
> UTC AEROSPACE SYSTEMS
> 3445 S. 5th Street, Suite 170, Phoenix, AZ 85040 U.S.A.
> Tel: 602 308 5957  FAX: 602 243 2347
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> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D
> Sent: Tuesday, February 27, 2018 10:19 AM
> To: [log in to unmask]
> Subject: [External] Re: [TN] Non Functioning pads
>
> I don't see why not, unless they are used for capacitance or antennae.
> If they are NOT used for those purposes, then they should be  
> removed for the same reason.
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Larry
> Sent: Tuesday, February 27, 2018 11:12 AM
> To: [log in to unmask]
> Subject: [TN] Non Functioning pads
>
> Is there any reason I cannot remove non functioning pads on the  
> inner layers for an Class 3 PCB?
>
> Many thanks,
>
> Larry