TECHNET Archives

January 2012

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:
residuguru <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, residuguru <[log in to unmask]>
Date:
Mon, 9 Jan 2012 10:51:07 -0500
Content-Type:
text/plain
Parts/Attachments:
text/plain (71 lines)
To address the point of localized cleaning of a water soluble flux with no rosin content and spot cleaning his problem is most likely the variable amount of flux residue still under the T-1 component and can be removed with enough flushing of the flux residue.  My recommendation is still steam (DI water) its quick and easy but hot DI water will work well too just takes more flushing.  Then we recommend a bake at least 65C for 2 hours.  I would also suggest that you have localized contamination analysis done on the specific area vs the typical ROSE test where its easy to miss the small pockets of contamination.  

Terry Munson



In a message dated 01/09/12 10:40:35 Eastern Standard Time, [log in to unmask] writes:
Wow Gary!

You ticked TechNet off man! Too bad It went into a different subject...  :-)

Going back to the problem you presented. Have you done Failure Analysis on the boards AND on the lamps to see what the failure mode is? By you mentioning Water Soluble Flux and Baking I am thinking that there should be oxidation somewhere.

Is the interconnection between the Lamp and the Printed Board what is failing or is the lamp failing internally?

If it is the interconnection you should be able to easily “see” the problem.

Rigo

Rigo

Sr. Quality Assurance Engineer
Workmanship Standards, Code 300 
NASA, Goddard Space Flight Center
Greenbelt, MD  20771
Phone. (301) 286-6129
Fax.       (301) 286-6576


-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Gary Bremer
Sent: Saturday, January 07, 2012 6:37 PM
To: [log in to unmask]
Subject: Re: [TN] Cleaning water soluble flux‏

I am presently working as an contractor for the next few months then back to unemployment, last place I worked was Jet Propulsion Laboratory on the Mars Science Laboratory.  These are lighted panels for various aircraft and the company policy is for J-STD-001/IPC-A-610 Class 3  The failure is with miniature T-1 lamps that stop working after going through an baking process.  Other boards that use these lamps but use RMA flux do not have this problem, I suspect the cleaning process and the flux.  They do not check ionic contamination and handle the boards with bare hands and the operators even know when components are ESD sensitive or not.  I have recommended they change the cleaning process to an Aqueous type batch cleaner but this cost money which they do not wish to spend.  Their process person believes that their process is fine and something else is causing the problem (bad lamps, forming lamp leads, etc.).  This goes against all my knowledge and training.

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 16.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

______________________________________________________________________
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] 
______________________________________________________________________


--------------------------------------------------- 
Technet Mail List provided as a service by IPC using LISTSERV 16.0 
To unsubscribe, send a message to [log in to unmask] with following text in 
the BODY (NOT the subject field): SIGNOFF Technet 
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) 
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest 
Search the archives of previous posts at: http://listserv.ipc.org/archives 
For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 
----------------------------------------------------- 

______________________________________________________________________
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] 
______________________________________________________________________
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 16.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

ATOM RSS1 RSS2