. . and subsequent versions, "never depend on solder for the mechanical strength of a joint". In other words, twist 'em together before you solder.
Check, good job. For a joint that requires high-strength, I use 2 additional things. Silver Solder, which has about 6 times the strength normal solder (or even eutectic solder) has. For wiring I twist the wires together AND use a copper crimp ring, this adds considerable integrity to the solder joint.

And no - there isn't a satisfactory substitute. Solder is a form of metalic glue that's highly conductive and bonds intimately with the substrate.
There is debate lately about that, but in general it is true. The debate has been in regards to new highly engineered conductive glues, which have been developed to speed electroncis manuacturing. None have made significant inroads to the solder-wave, but they are starting to show up in strange places.

Now, while recognizing the wisdom of the first paragraph, I have violated it many times with good results. Several factors are essential, however:
  • Use a good quality rosin core solder - NEVER acid core (that's for roofing work).
  • Use a soldering iron of appropriate size and with good heat control - never us a "soldering gun". Those abominations even the Devil will deny inventing.
  • The wires must be bright and clean of any corrosion
  • Heat the wires, not the solder. The wires must be hot enough to melt the solder so it flows over them and makes a good bond.
  • Do not disturb the joint at all until the solder has cooled solid. If the joint has a matt finish rather than shiny bright it's been disturbed and isn't going to hold.
  • Once finished with heat, completely clean the rosin-flux residue from the board or wires, using an alcohol wash solution with some form of cleaning implement (toothbrush is my choice). (added by Greg)


"If God had meant man to solder, He'd have given him three hands".
Errm, no comment.