Chuck(G)
25k Member
For 63-37 tin-lead solder, 370F works pretty well. About the same temp for some nice oatmeal cookies. 
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The great Capacitor thread
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rebeltaz
Experienced Member
For 63-37 tin-lead solder, 370F works pretty well. About the same temp for some nice oatmeal cookies.
And the time in the oven doesn't harm any of the component?
I'll have to try that on my stockpile of surplus boards!
Ole Juul
Veteran Member
And the time in the oven doesn't harm any of the component?
It depends on whether you like your chips runny or not.
Chuck(G)
25k Member
I don't salvage the low-value components (i.e. capacitors, resistors, etc.) but the heat doesn't seem to bother ICs at all. It's probably no worse than a charcoal fire or a hot-air rework tool--and maybe better as there are fewer thermal stresses in an evenly-heated board.
The weapon of choice in depopulating old PCBs used to be a propane torch. Turn the board component side down, wave the torch over the top side and wait for the ICs to fall off. That was pretty crude and very smelly and probably dangerous to your health.
To rework a board with SMT, I use a homebrew version of Quik-Chip; Cerrobend 158 applied as a powder and heated to less than 200F with a spotlamp applied to the reverse side. Even fine-pitch TQFPs pop right off without damaging the board traces at all. Clean, flux and solder the new chip in normally.
Sorry for the off-topic rambling...
The weapon of choice in depopulating old PCBs used to be a propane torch. Turn the board component side down, wave the torch over the top side and wait for the ICs to fall off. That was pretty crude and very smelly and probably dangerous to your health.
To rework a board with SMT, I use a homebrew version of Quik-Chip; Cerrobend 158 applied as a powder and heated to less than 200F with a spotlamp applied to the reverse side. Even fine-pitch TQFPs pop right off without damaging the board traces at all. Clean, flux and solder the new chip in normally.
Sorry for the off-topic rambling...
Ole Juul
Veteran Member
>Chuck(G): "Sorry for the off-topic rambling..."
Actually, I find it quite on topic. Electronics seems to be a "dated" hobby and the average, so called, nerd nowadays couldn't solder his way out of a paper bag - so your ramblings are quite refreshing!
Back to caps, specifically. It is worth noting when dealing with temperatures, that they usually come in temperature ranges. Something like 80C or 100C. That is quite low, so one can expect them to fail in many places where heat accumulates. Also, there is a nice overview of cap types and their uses at radio electronics: http://www.radio-electronics.com/info/data/capacitor/capacitor_types.php
The charts there are also good for deciding on which type to use. That, of course, also depends on what you can get your mitts on.
Actually, I find it quite on topic. Electronics seems to be a "dated" hobby and the average, so called, nerd nowadays couldn't solder his way out of a paper bag - so your ramblings are quite refreshing!
Back to caps, specifically. It is worth noting when dealing with temperatures, that they usually come in temperature ranges. Something like 80C or 100C. That is quite low, so one can expect them to fail in many places where heat accumulates. Also, there is a nice overview of cap types and their uses at radio electronics: http://www.radio-electronics.com/info/data/capacitor/capacitor_types.php
The charts there are also good for deciding on which type to use. That, of course, also depends on what you can get your mitts on.