Hello Doug,
Your email is fortuitous, as we are now experiencing a major cleaning issue after a recent change of cleaning solvent. On a more elementary level, because that is the level of cleaning knowledge here, it would be great to understand the following:
1) Related to cleaning chemistry and processes, what is the best process to select a new solvent/de-fluxer? Last year, we were finally forced to ditch the very much liked Ensolv (nPB/1-Bromopropane). I tried to start a campaign to get rid of Ensolv back in 2013 to no avail. The evaluation of nPB-free replacements involved testing 4 alternatives, but only qualitative data was used for evaluation. Because of the previously mentioned problem, starting soon is another round of testing and we will be evaluating quantitative data using SIR, FTIR or IC. I also heard we are getting a ROSE tester. We have never done any cleanliness testing here in the last 50 years. Yes, bad habits are going to be hard to break!
2) Related to flux chemistry, what else on the CCA are we cleaning, or need to clean? Important in my division, because we do NOT have a policy that requires gloves or finger cots when handling boards. Worse yet, is that it could be 3 months between assembly/de-fluxing and conformal coat, with many people handling the boards for testing in that time. Yep, bad habits!
3) How about dialing in a cleaning process? Is the best way to achieve this by performing a factorial design (fractional or full)?
4) Is there anything specific to space systems, regarding cleaning processes that we need to understand?
Sorry for my biases on this subject, but they are real, albeit probably a minority of the TechNet community. Thanks in advance for your work on this subject, and when do you think you will have a course of study ready - maybe next week?:)
Regards,
Howard A. Watson
__________________________________________
Intelligence & Space Research Division, ISR-5, TA-03-2322-504
Los Alamos National Laboratory
30 Bikini Atoll Road
Los Alamos, NM 87545
Phone: 505-665-3402
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-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Douglas Pauls
Sent: Wednesday, February 26, 2020 5:43 AM
To: [log in to unmask]
Subject: [EXTERNAL] [TN] Cleaning Course of Study
Good morning Technetians
OK, so I have been thinking (and we know how dangerous that is) about developing a course of study for someone to become a "cleaning expert".
Something along the lines of starting with a new hire and educating the new hires up to my level. Courses would include things like flux chemistry, cleaning processes and chemistry, cleanliness measurement methods, SIR methods, etc. What items would you suggest be added to the course of study?
*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
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