Electronics Forum | Mon Apr 14 20:13:40 EDT 2014 | davef
So, someone is going to get a chance to buy a nice and shiny oven, eh? Summary from my notes of old thread on SMTnet: Some people melt sugar and use that solution to clean cooked-on flux residue. Dissolve sugar into warm water, spray it on the area t
Electronics Forum | Tue May 20 18:38:23 EDT 2014 | hegemon
From the picture I would say the problem lies with the PWB manufacturer. It looks as though some part of the plating process was not optimal during the PWB production run, and you have the resulting discoloration following the reflow process. What
Electronics Forum | Wed Aug 06 14:49:06 EDT 2014 | dyoungquist
Sn62Pb36Ag2 has a higher liquidus point of 189C as compared to Sn63Pb37 at 183C. You may need to slightly adjust your oven profiles to use it compared to SnPb. We have had good solder-ability and reliability with it in our IPC Class II products. A
Electronics Forum | Wed Mar 11 17:32:46 EDT 2015 | jlawson
Small paste deposits have less flux thus less flux activity to enhance the wetting. So preheat needs to be as short as possible, ramp to spike if possible. Try not to ramp hold and spike - pending thermal delta on product can be made to ramp to spike
Electronics Forum | Fri May 22 12:42:43 EDT 2015 | deanm
Sr. Tech, you are right in that there is no verification of the profile. We are a Class 3 high mix OEM. We have visual inspection after SMT. We have not seen problems with wetting, grainy solder, cold solder, charred boards, etc. that would indicate
Electronics Forum | Mon Aug 24 17:58:10 EDT 2015 | warwolf
We have had some test results come back after we were getting poor wetting in our joints, we requested an EDS on our joints from our PCB supplier. They have provided the results and said that it was their fault and will replace. What I want to know
Electronics Forum | Tue Sep 15 14:11:59 EDT 2015 | jpal
You should also remove all the pump parts and clean them, checking the bearings and seals. Clean completely the parts that allow the solder to flow back into the pot; ours have a spiral that fills with dross. Treat yourself to new nozzles. Tinning
Electronics Forum | Wed Dec 09 10:45:56 EST 2015 | huske
I've put down a SOT223, close enough to your 3pin transistor, in the same situation you have. The large pin was to be soldered on a large exposed ground plane in the corner of a board, over 2"x2" exposed area. We left the paste file as is, so where
Electronics Forum | Fri Nov 25 05:16:44 EST 2016 | slavek
Hello, I want to ask on suitable temperature profile for PCBs with ENIG final surface finish. I know that it is complex question with many unknowns. When the PCB will be standard 1,5 mm 35/35 Cu and the amount of components will have any influence o
Electronics Forum | Mon Jun 05 18:50:10 EDT 2017 | caurbach
Hi Zac, My 2 cents: We had similar problems on a board in the same situation (tin-lead HASL, very long leads, low pot height, high pump RPM). Trimming the leads shorter, moving the pot closer to the board, and dropping the pump speed down to sane
