[time-nuts] Wenzel Oscillator Repair

[Joseph M Gwinn]

time-nuts-bounces at febo.com wrote on 01/20/2009 04:32:15 PM:

> Bruce Griffiths skrev:
> > The relatively low thermal conductivity of the steel can will help
> > considerably in avoiding thermal damage if the heat is 
> applied to the joint.
> > If the can were copper it would be much more difficult to avoid 
thermal
> > damage.
> 
> When I needed to have a McCoy oscillator can opened my trusty good old 
> friend Sten did the usual trick of pre-heating the can and then when 
> applying heat to the solder the thermal difference is lower and hence 
the 
> heat-flow away from the joint. Didn't take much time and I think the 
> oscillator is 100% intact.
> 
> Pre-heating and hot air are his main tools for tricky soldering jobs. He 

> has low fatality rate on problems like that. This is why we let him do 
> that kind of stuff at work.

I imagine that Sten works *very* fast.  I've found that when soldering 
thermally sensitive things like small coil bobbins made of nylon that a 
high temperature and relatively large iron is best - the terminals come up 
to temperature almost instantly, and it's all over before the heat can 
spread and melt the bobbin.

Hot air has the advantage over a flame that overtemperature is less likely 
with hot air.

Joe