Chris,
It is always remarkable that we have potential conflicting language in
our documents for years before someone asks for an interpretation. This
was a great example. 
The "no soda strawing" requirement came from the danger of soda straws
starting from a coverlay opening and allowing chemicals to wick up the
capillary "straw" next to bare copper. 
Nick has a point, when soda straws are isolated within the circuit, with
no possible connection to an opening they could be "non-lamination  
Again, a need for an improved description for the next revision.
Regards,      

Clark Webster
Ph: 507.663.7162 Fax: 507.663.1070
[log in to unmask]
 
-----Original Message-----
From: IPC-600-6012 [mailto:[log in to unmask]] On Behalf Of Nick Koop
Sent: Tuesday, September 01, 2009 8:17 AM
To: [log in to unmask]
Subject: Re: [IPC-600-6012] sodastrawing

Chris,

I can see the potential for conflict as we say no soda strawing.
however, I would apply the 25% "nonlamination" limit to the soda
strawing.

My two cents.

Nick

Nick Koop
Sales Director
Minco Products, Inc
Ph 763 586-2846
Mobile 763 245-4825


>>> Chris Mahanna <[log in to unmask]> 8/31/2009 8:40 PM >>>
Hi all,

A customer has ask me to query the group about coverlayer sodastrawing.

From the applicable paragraphs in 6013 and 600, one could interpret
sodastrawing as completely unacceptable unless it is a "nonlamination" ,
in which case it can reduce dielectric spacing by 25%.
Unfortunately there appears to be a disagreement about whether
sodastrawing is to be included as a nonlamination.

Thanks,
Chris