Soldering

speakerman1

speakerman1

Honorary Forum "Larrt" (ornery too)
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Jun 12, 2010
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OZONE ALLEY MARS (Visitor)
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Wasted Days and Wasted Nights
I have a problem. I can't get solder to stick to a board I am working on. I have cleaned it. Tried flux, cleaned it again. I have run the gambit on iron temps. In my life I have never had this problem. What should I do? I have spent hours trying to solder 2 resistors onto this board.

Larry
 
I tried reading a little online about this problem. A clean and tinned tip on the soldering iron itself helps to transfer the heat better to the parts. Some say this is key.
 
Have done that a bunch of times. I never let my tips get dirty. I know by tinning it will transfer heat better. The solder just doesn't want to go to the board. I have never had this happen before. It is now going on 5 days of dicking with 2 resistors.
 
Do you have a picture of the area you are trying to solder? That might be helpful.

Jim
 
It is really small and looks really nasty since I have tried so many times. I would be embarrassed. LOL
 
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Could there be some type of conformal coating on the board? What did you try cleaning with? I would try a different cleaner, flux, and solder. Clean, clean, clean is usually the key to soldering.

Robert
 
I used Contact cleaner wash, alcohol wipes to clean. Used q tips with the wash. Used Chip quik flux. I have cleaned the board 5 times. It sticks to the wires and my iron but will not stay on the board or suck down into the hole. I am about to pitch the whole thing. Wondering if I could etch the board with vinegar or something acidic.
 
I would try acetone or lacquer thinner...... Use a Q-tip and be very careful around any plastic. No idea what is in the things from RS.

Robert
 
Like they said Larrt, send us a picture. We don't care what it looks like. Cannot help if you do not show us what you are trying to do.

Some boards use OSP (organic surface protectant) coating over bare copper pads rather than the more common tin-lead HASL (hot air solder leveling) coating. OSP is used on a lot of SMT boards because it provides a nice co-planar soldering surface. Once the OSP has run through wave solder or IR reflow once, it removes the OSP and exposes bare copper to the elements and you have a devil of a time soldering to it after some time has passed. When I run into a board like this I carefully polish the pad with an ink eraser (remember those) until the pad becomes bright and shiny again. Then in conjunction with a good activated rosin core solder, you can solder to the pad again. If you have zorched the pad by repeated attempts to solder to it, the adhesive that bonds the etch to the PCB laminate eventually gives up and separates from the board. If this has occurred, you have board repair on your hands. If you have conformal coating on the board, that is really tough to clean off to allow soldering to.

Again, a picture would be helpful in letting us help you.

Joe
 
Had similar problems on some old Accuphase boards and the only solder that worked on them was some solder that my tech found in his collection with no clean flux. Do not remember the tin/lead ratio.
 
Am I doing something wrong? I have read about upgrades to the Bellari they never said they had a problem. OK I just tried every way I know. Will try lacquer thinner. Or should I not? It jumps right off the board onto the wire or the iron. It will not flow. Should I just throw the SOB out?
 
It is the board. I just soldered to a bare trace but would not stick to the board. I cleaned with Xylol and nothing. Will find my thinner.
 
John told me to follow the traces and see if I can solder the leads to another solder pad and do that. LOL I got mad and threw my last 100K some where. LOL
 
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