TECHNET Archives

February 2013

TechNet@IPC.ORG

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 >>]

Print Reply
Subject:
From:
Inge Hernefjord <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Inge Hernefjord <[log in to unmask]>
Date:
Mon, 4 Feb 2013 16:09:27 +0100
Content-Type:
text/plain
Parts/Attachments:
text/plain (102 lines)
Speaking cleanliness, I participated in making visual inspection of some
artillery radar stations which had been in Afghanistan and Iraq. I was
struck by the way desert sand can creep in every where, despite filters,
filters and filters. The pH of dry sand is nearly neutral, but with
addition of humidity, it's far from harmless. I don't know how many of you
work with MIL stuff. Anyway, the report "Iraqi sand" should be on your desk
for newbies to learn about corrosion. C. costs the US gov astronomic lots
of money, and much can be avoided, but will not be successfully reduced
until all be interested in 'corrosion'. Which is not the case. Enough said,
read under map *Corrosion and ....'.  Title is 'Iraqi sand".  Lots of folks
in the eletronic industry still think deserts are dry and nice places for
their products. Wrong!

Inge

On 4 February 2013 15:28, Watson, Howard A <[log in to unmask]> wrote:

> Hi Lloyd,
>
> That makes sense. One of my concerns is the repeatability of the onboard
> cleanliness tester. I have read that proper calibration of the resistivity
> probe would be very difficult, due to the turbulent nature of the flowing
> water, so I think it does make sense to use another tester like you say to
> validate the washing machine. If you don't mind, I might contact you
> offline with specific questions on the Trident.
>
> Thanks!
>
> Howard A. Watson
> Phone: 505-665-3402
>
> -----Original Message-----
> From: Lloyd Duso [mailto:[log in to unmask]]
> Sent: Friday, February 01, 2013 3:21 PM
> To: 'TechNet E-Mail Forum'; Watson, Howard A
> Subject: RE: [TN] Manncorp Trident Batch cleaner Onboard Cleanliness tester
>
> We have the exact machine here and use it often. The cleanliness testing
> portion is useful to set a range and let it rinse until it reaches that
> point. It in no way replaces a task specific cleanliness tester like a
> Zero-Ion or an old school Omega. Since it is a batch machine, the
> cleanliness is just an average not a specific count for one board. The
> benefit is that if it reaches the cleanliness value programmed in on the
> first rinse it's done. If it hasn't reached that value it will keep rinsing
> until it hits the programmed Max Rinse number. We still use the cleanliness
> tester to validate the washing machine.
>
> Lloyd E Duso
> Plant Manager
> (814) 535-3505
>
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Watson, Howard A
> Sent: Friday, February 01, 2013 4:47 PM
> To: [log in to unmask]
> Subject: [TN] Manncorp Trident Batch cleaner Onboard Cleanliness tester
>
> Hi all,
>
> My shop just bought a batch cleaner (dishwasher type); the manual says it
> is Aqueous Technologies, with an onboard cleanliness tester. This is a
> resistivity meter that measures the resistance of the rinse water, and I
> believe it has a range of 2k to 2000k ohm. This unit has both a closed-loop
> wash and  rinse, and we are using DI water. Does anyone have any experience
> with this type of cleaner with an "onboard cleanliness tester"?  Is this
> mostly for process control?  The manual is recommending a baseline
> cleanliness of 200-400 kOhm. I realize that this tester is not going to
> provide a level of cleanliness or contamination of each board processed,
> but I'm not sure what it is good for other than indicating the rinse water
> needs to be changed.
>
> I was not involved in the selection of this system, but tasked with
> qualifying it.  My previous experience has been with no-clean processes, so
> cleaners are new to me!  I should add that currently we process a very
> small volume of PCBAs for space. All work is hand assembly and cleaning is
> by hand with Ensolv. The goal is to get away from Ensolv while still
> achieving clean boards. This shop has never done ionic contamination
> testing, ROSE, SIR, etc.  I believe some people were sold on the "onboard
> cleanliness tester" as a cure-all for aqueous cleaning validation, but I'm
> skeptical as to the benefits.  Any insight is appreciated.
>
>
> Howard A. Watson
>
>
> ______________________________________________________________________
> 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]
>
> ______________________________________________________________________
> 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]
> ______________________________________________________________________
>


______________________________________________________________________
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