LISTSERV - TECHNET Archives - LISTSERV.IPC.ORG

TECHNET Archives

March 2013

TechNet@IPC.ORG

	LISTSERV Archives
	TECHNET Home
	TECHNET March 2013

	Log In
	Register

	Subscribe or Unsubscribe

	Search Archives

Options:	Use Monospaced Font Show Text Part by Default Show All Mail Headers
Message:	[<< First] [< Prev] [Next >] [Last >>]
Topic:	[<< First] [< Prev] [Next >] [Last >>]
Author:	[<< First] [< Prev] [Next >] [Last >>]

Subject:	Re: Notes in PCB Fabrication
From:	"Upton, Shawn" <[log in to unmask]>
Reply To:	TechNet E-Mail Forum <[log in to unmask]>, Upton, Shawn
Date:	Fri, 1 Mar 2013 15:52:46 +0000
Content-Type:	text/plain
Parts/Attachments:	text/plain (1 lines)

I know for us, maybe not others, there were issues in the past with underetch.  We do a lot of gold plate, hard gold plate, and underetch is an issue, as is getting flat copper pads.  I know the vendor explained it, and of course I've managed to forget...  Which is why we no longer specify starting and finish copper.  But I think that is the case: underetch, hard gold plate, that some people want to / need to spell it out.

Shawn Upton, KB1CKT
Test Engineer
Allegro MicroSystems, Inc
[log in to unmask]
603.626.2429/fax: 603.641.5336


-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Pete
Sent: Friday, March 01, 2013 10:37 AM
To: [log in to unmask]
Subject: Re: [TN] Notes in PCB Fabrication

It makes sense, in that they want 1/2 oz plating over 1/2 oz foil as a base copper.  Any final finish specification (ENiG) should be a separate note, as the notes refer to 2 different requirements.

It doesn't make sense, in that the foil/plating ratio shouldn't matter to the customer (except in very rare cases), but it DOES make a difference to the fabricator.

I have just finished updating our very old boilerplate notes.  One of the changes was to remove the foil/plating note, very similar to the one you referenced.  Our vendors regularly complained about not having the option to use what was best for their process.  We now only specify finshed copper thickness.  I have no idea why that was originally done, other than the possibility of having some control over hole plating.  That also isn't really required, since IPC-6012 was always specified anyway, covering hole plating minimums.

Pete

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please visit http://www.symanteccloud.com ______________________________________________________________________

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________

ATOM RSS1 RSS2

LISTSERV.IPC.ORG