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  That was my basic training guide.   Back in the early 80s

Victor,

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Yuan-chia Joyce Koo
Sent: Monday, March 5, 2018 10:01 AM
To: [log in to unmask]
Subject: Re: [TN] Non Functioning pads

well said dinosaur... look like we are similar vintage...
On Mar 5, 2018, at 10:48 AM, Jack Olson wrote:

> I must be behind-the-times on this one.
> Werner Englemaier used to talk about this all the time, and from my 
> memory an analogy might be similar to comparing a simple rivet to a 
> "rivet with ribs". If your goal is a robust product (which a lot of 
> Class 3's are) then it seems like you would want the extra support.
> (I'm not making a statement, I'm repeating what I was taught). I'm 
> pretty sure I've heard Gary Ferrari recommend keeping them in at least 
> a half a dozen times in his seminars. Aren't the most common failures 
> in boards related to vias?
>
> Maybe I have more learnin' to do on this one, but I'm surprised that 
> NO ONE responded in favor of keeping the unconnected internal pads
>
> Well, since we are talking about vias, I was also advised to require 
> 1mil hole wall plating, even though the standard is 0.8 (I think). But 
> for the same reason, the stronger we can make our vias, the less "most 
> common" failures we will have, right? (At Caterpillar, we want the 
> most robust product we can get for the
> money) Am I sounding like an old dinosaur now?
>
> but really, is EVERYONE removing unconnected inner layer pads?
> Is "increasing the longevity of drill bits" the dominant theme now?
>
> onward thru the fog,
> Jack
>
>
> .
> On Tue, 27 Feb 2018 11:12:22 -0600, Larry <[log in to unmask]>
> wrote:
>
>> Is there any reason I cannot remove non functioning pads on the inner 
>> layers for an Class 3 PCB?
>>
>> Many thanks,
>>
>> Larry