Groan!  😊

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Stadem, Richard D
Sent: Monday, January 6, 2020 9:48 AM
To: [log in to unmask]
Subject: [TN] NTC: [TN] [External] [TN] immersion gold thickness

What you really should do is have the antimony scraped off of the top of the solder pots daily and set it aside and save it. It contains some gold, which gives molten solder that slightly golden hue on top after the dross is removed.
Why would you want to do that?
Well, I have heard that if you go through a divorce, your ex will demand (and usually will be rewarded) antimony by the courts.
Nothing closes out a divorce proceeding faster than you rolling in a pallet loaded with bars of antimony into the courtroom. I know Steve Gregory saves his; he once provided a link to his stockpile.
So you want to have lots of antimony stockpiled, just in case!  :-)


-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Campbell, Murray
Sent: Friday, January 3, 2020 3:53 PM
To: [log in to unmask]
Subject: Re: [TN] [External] [TN] immersion gold thickness

Haha, I'll take the 15inches of gold off at incoming inspection and put it towards my retirement!  Apparently it didn’t like my micro symbol, how about 15 micro inches



-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Douglas Pauls
Sent: Friday, January 3, 2020 2:48 PM
To: [log in to unmask]
Subject: Re: [TN] [External] [TN] immersion gold thickness

Ya gotta wonder how long it takes to plate up 15 INCHES of gold......

*Douglas Pauls *| Principal Materials and Process Engr | Advanced Operations Engineering

*COLLINS AEROSPACE*

400 Collins Road NE, MS 108-101, Cedar Rapids, IA  52498  USA

*Tel:* +1 319 295 2109 | *Mobile: *+1 319 431 3773

[log in to unmask]

[log in to unmask] for all Export Compliant Items


On Fri, Jan 3, 2020 at 3:45 PM David Hillman < [log in to unmask]> wrote:

> Hi Murray - if you can get a true ENIG plating chemistry to put 15 
> inches of gold thickness on a board, you would never want to use the 
> board as the gold plating would have severe structure and/or 
> solderability issues. The IPC-4552 specification contains the industry 
> consensus gold plating thickness range that applies to producing an 
> acceptable and reliable ENIG plating layer. Any gold plating thickness 
> outside of that range would be questionable at best for quality and 
> reliability unless you are working closely with a plating chemistry 
> supplier who is doing a custom plating bath composition. One of the 
> early issues of ENIG plating was the industry asking the plating 
> chemistry suppliers to provide an immersion gold plating thickness 
> that exceeded the acceptable physics of the plating chemistry (basically this is how we discovered "black pad"!).
>
> Dave Hillman
> Collins Aerospace
> [log in to unmask]
>
> On Fri, Jan 3, 2020 at 3:30 PM Campbell, Murray 
> <[log in to unmask]>
> wrote:
>
> > Happy New Year All,
> >
> > Is there any good reason to call out a maximum gold thickness / 
> > nickel thickness on fab notes or is it sufficient to rely on simply 
> > stating that the fabricator shall follow ipc-4552 minimum thickness?
> > I have seen some companies state that a maximum thickness upwards of
> > 15 µin to be acceptable.  Is there any value in stating an upper range?
> > I know it states in 4552 that an upper range had been debated and 
> > not necessary but I still see an upper added to fab notes.
> >
> > Regards,
> >
> > Murray Campbell
> > PCB Design Specialist
> > [log in to unmask]<mailto:[log in to unmask]>
> > [cid:[log in to unmask]]
> >
> > "This message and/or attachments may include information subject to 
> > GD Corporate Policies 07-103 and 07-105 and is intended to be 
> > accessed only
> by
> > authorized recipients. Use, storage and transmission are governed by 
> > General Dynamics and its policies. Contractual restrictions apply to
> third
> > parties. Recipients should refer to the policies or contract to 
> > determine proper handling. Unauthorized review, use, disclosure or 
> > distribution is prohibited. If you are not an intended recipient, 
> > please contact the
> sender
> > and destroy all copies of the original message."
> >
>
“This message and/or attachments may include information subject to GD Corporate Policies 07-103 and 07-105 and is intended to be accessed only by authorized recipients. Use, storage and transmission are governed by General Dynamics and its policies. Contractual restrictions apply to third parties. Recipients should refer to the policies or contract to determine proper handling. Unauthorized review, use, disclosure or distribution is prohibited. If you are not an intended recipient, please contact the sender and destroy all copies of the original message.”