White deposit on solder side of PCB

Gerald Ball

Have completed 2 x QCX now without problem and both working perfectly. But have noticed that on both boards I have a musty ( for want of a better word) white deposit around all solder connections. Could this be too much heat, type of solder I am using or just a function of the board coating. Has anybody experienced this? Would appreciate your comments please as am awaiting delivery of my third QCX and would like to avoid the same thing developing if possible. 
gerry G4OJF

SkipF, NT1G <skip.flem@...>

There a jillion reports on google referring to this 'harmless'
 (their words) white substance. Most likely it is flux residue...
 (that's the common suggestion) possibly from 'no wash flux'.
 WHAT did you find?

Gerald Ball

Hi Skip

Thanks for reply and advice. sometimes I don,t think about the wonders of google (or maybe most of the time I just don't think!)
Anyway a drop of contact cleaner and a toothbrush and now all clean.
Thanks again gerry G4OJF