Electronics Forum | Fri Apr 03 08:22:36 EST 1998 | Scott Cook
| At this moment in time we are using water soluble solder paste on our PCBs these are cleaned using water only, agitated with ultrasonics. After drying a white/grey residue is left around solder joints. Reflow profile is fine and a reliable wash pro
Electronics Forum | Mon Jan 09 13:11:07 EST 2006 | Joe
I assume you're using a no clean Pb/Sn paste, with a metal squeegee. Here are some generic procedures for good printing results for all pastes. Clean and dry the stencil well using alcohol and vigorously rubbing it with lint free towels, blow it off
Electronics Forum | Thu Jul 06 07:30:46 EDT 2000 | John
Ralph, Typically our co-op students put down solder paste with a syringe, place the parts on the paste with tweezers, and then reflow the paste with a hot air pencil. This works pretty well when they are hand building prototypes. You can probably
Electronics Forum | Thu Feb 12 12:30:16 EST 2015 | stevezeva
I remembered something from the TechNet a long time ago about heating the board with a heat gun to see if the white spots disappear. I searched the archives and found this from Bill Kenyon: Quick identification of solder mask white spots- if it is t
Electronics Forum | Wed Sep 30 13:54:00 EDT 1998 | Chrys
All y'all | | BACKGROUND. How many times do you see folks come to work all painted-up and then by the time first break comes, the lipstick, eye liner, and who knows what else are gone and they�re heading for the facilities to "freshen-up." I w
Electronics Forum | Fri Oct 02 16:52:38 EDT 1998 | Dave F
All y'all | | | | | BACKGROUND. How many times do you see folks come to work all painted-up and then by the time first break comes, the lipstick, eye liner, and who knows what else are gone and they�re heading for the facilities to "freshen-up."
Electronics Forum | Fri May 26 04:58:19 EDT 2023 | auriga2001
I agree with the two other replies. Left alone, it is a defect. If it's just excess adhesive or coating, you can use IPC-7711/7721 'Rework, Modification and Repair of Electronic Assemblies' for guidance on removing. Section 2.3.1 explains how to te
Electronics Forum | Thu Feb 18 22:49:49 EST 1999 | Chris G.
| We are using .040" diameter fiducials (global and local) on our boards. They are solder covered and HASL. I get batches of boards where the p&p vision system has trouble reading the fiducial. The fiducial looks dark on the screen. The board ven
Electronics Forum | Sat Aug 18 22:43:14 EDT 2012 | eadthem
we service all of our lightning spindles once a year, Take the spinldes off. loosen the screw by the nylon cap and slide the locking pin out. run the spindle shaft, the nylon cap and pin assembly , and spring thrue a ultrasonic cleaner with 99% is
Electronics Forum | Wed Jan 27 09:00:56 EST 1999 | Chris Fontaine
| | I have boards coated with Humiseal 1B73. At a late point mfg. site we need to remove a series of 0603 resistors for optioning purposes. I have been trying to determine the fastest, easiest way to re-coat the pads after removal. Drying time of the
