Another option would be to panel plate, then print and etch the outer 
     layers (assuming HASL or other finish)


______________________________ Reply Separator _________________________________
Subject: Re: Pulse plating of copper and tin/lead
Author:  [log in to unmask] at INTERNET_GATEWAY
Date:    3/19/97 3:57 PM


     
>I am working to resolve a problem in pattern plating a panel which has a ground
>plane on one side (40% plated panel area) and pads on the back side (6% plated 
>panel area).  We use modern DC rectifiers, one for each side, which share the 
>cathode connection.  The panels overplate the back (6%) side even with the 
>corresponding rectifier turned off.   Our only solution was to place current 
>robbers on the back side which are selectively etched off in a later operation.
     
>I have been given information that "pulse plating" could allow us to plate this
>design with out any modifications to the plating areas.  My question is:
>
>1. Does anyone currently use "pulse plating" in a pattern plating operation? 
>2. Would this technology make plating this type of unbalanced design easier? 
> 
>
>Thanks,        Rick Haynes
>              Texas Instruments Printed Circuit Resources 
>              512-250-7823   [log in to unmask]
>
Hi Rick,
     
Have you thought of panel plating the copper and then imaging to pattern 
plate the tin-lead. We do this on some unplateable designs and it solved 
the problem completely.
Paul Gould
Teknacron Circuits Ltd
     
*************************************************************************** 
* TechNet mail list is provided as a service by IPC using SmartList v3.05 * 
*************************************************************************** 
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   * 
* with <subject: subscribe/unsubscribe> and no text in the body.          * 
*************************************************************************** 
* If you are having a problem with the IPC TechNet forum please contact   * 
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      * 
***************************************************************************
     

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   *
* with <subject: subscribe/unsubscribe> and no text in the body.          *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact   *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      *
***************************************************************************