High Performance Electronic DesignRemoving unused pads on internal layers
does not affect pth integrity.
3 questions to identify the problem:
    1.) Do the leads of your components extend through the board?
    2.) Do you provide thermal relief's on massive copper connections and
planes?
    3.) What is the min plate thickness inside barrel?

Randy Jackson
Design Center Manager
DFW Test Inc.
Phone (972) 231-1094
Fax (972) 231-1895

  -----Original Message-----
  From: DesignerCouncil [mailto:[log in to unmask]]On Behalf Of Bremer,
Gary
  Sent: Monday, June 24, 2002 9:43 AM
  To: [log in to unmask]
  Subject: [DC] High Performance Electronic Design


  I am forwarding this question from one of the design engineers at work.
We advertise we build class 3 products, but with all of our thick boards, we
get open traces whenever a hand soldering operation is required.  We just
found out that one of our board vendors has been removing all the unused
pads on the inner layers without out knowledge.  The board type we generally
use for our backplanes is type 3c per IPC-2222.

  Does getting rid of unused pads on all inner layers have any profound
affect on the PHT barrel integrity especially with high layer count / thick
circuit boards?

  Thanks for your help,

  Gary Bremer
  Manufacturing Engineer
  Phone (626) 449-3090 ext. 219