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Gene in NC
04-09-2006, 07:15 PM
Attached are tips from EE with broad expereience in electronic design re "resoldering". A DIY guy who owns plane and other stuff with less demanding reliability reqmts.
---------------------------
Gene,
I have seen many examples of solder joint failure where high
current connections are made between printed circuit boards and relay
points. The current density at such connections is high enough to
fatigue the solder after a time and cause a "cold" or intermittent
connection. The best solution would be to use a
solder sucker to remove the old solder (melted), and then replace with fresh
solder. The heat and reflow method will leave oxidized particles from
the old joint that may cause a resistance high enough to cause the same
problem again.

The picture in the link you provided shows closely spaced connections
that may become bridged if you are not very careful with the soldering
tools.

http://www.bmwe34.net/E34main/Maintenance/Electrical/LKM.htm

Radio Shack has the tools you need. A 25-35 watt soldering iron will do the job. They have manual type solder suckers. Both should be less than $15 total. If you don't already have some get a roll of good electrical solder. DO NOT USE ACID COE PLUMBING SOLDER. It will destroy the device. Just take your time and watch that you don't bridge solder to adjacent joints.

shogun
04-09-2006, 07:37 PM
see my website below, for that I have included this

Basic Electronics Soldering & Desoldering Guide -english-

http://tridem.han-solo.net/auto/erich/auto.htm

misfortune
04-09-2006, 08:10 PM
As an EE major I must say that this should be common knowledge for most people who have toyed with electronics for a while. Having an EE degree is a bonus. :) Wish I had mine.


Attached are tips from EE with broad expereience in electronic design re "resoldering". A DIY guy who owns plane and other stuff with less demanding reliability reqmts.
---------------------------
Gene,
I have seen many examples of solder joint failure where high
current connections are made between printed circuit boards and relay
points. The current density at such connections is high enough to
fatigue the solder after a time and cause a "cold" or intermittent
connection. The best solution would be to use a
solder sucker to remove the old solder (melted), and then replace with fresh
solder. The heat and reflow method will leave oxidized particles from
the old joint that may cause a resistance high enough to cause the same
problem again.

The picture in the link you provided shows closely spaced connections
that may become bridged if you are not very careful with the soldering
tools.

http://www.bmwe34.net/E34main/Maintenance/Electrical/LKM.htm

Radio Shack has the tools you need. A 25-35 watt soldering iron will do the job. They have manual type solder suckers. Both should be less than $15 total. If you don't already have some get a roll of good electrical solder. DO NOT USE ACID COE PLUMBING SOLDER. It will destroy the device. Just take your time and watch that you don't bridge solder to adjacent joints.