I have some 20 year old silver loaded paint/ silver conductive paint
Electrolube SCP003 ,kept in a 35mm film pot, in fridge. It cannot be called
paint now, but not totally dried out, more like paste. I mixed a little with
the resin part of some also quite ancient but good epoxy , bulk 1kg purchase
about 10 years ago, also kept in fridge (red cap = resin ? any standard ?)
Left the mixture overnight and it was same pastiness, ie no/little cross
reaction.
Prepared a pair of 1.65mm wide , flat , brass pins, by cleaning with
methylated spirits only and drying off, deliberately no abraiding. One pin ,
wrapped 2 separated loops of 0.02mm insulated wire around as a precise
separator.
2 hours ago wixed with the hardener and placed between the spaced crossed
pins, held with a wooden clothes peg , holding force about 0.5 Kg.
I just tried measuring resistance between pins. Did not think , in advance,
about soldering fine wire to the pins for ohms testing. Connecting 2 croc
leads to the crossed pins, still with clothes peg, resistance varied between
3 and 35 ohm , holding in fingers. Highly sensitive to slight forces in
semicured state.
Will let it cure until tomorrow and retest conductance and also peel/sheer
strength of the epoxy. To be continued

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

N_Cook wrote in message
...
I have some 20 year old silver loaded paint/ silver conductive paint
Electrolube SCP003 ,kept in a 35mm film pot, in fridge. It cannot be
called
paint now, but not totally dried out, more like paste. I mixed a little
with
the resin part of some also quite ancient but good epoxy , bulk 1kg
purchase
about 10 years ago, also kept in fridge (red cap = resin ? any standard ?)
Left the mixture overnight and it was same pastiness, ie no/little cross
reaction.
Prepared a pair of 1.65mm wide , flat , brass pins, by cleaning with
methylated spirits only and drying off, deliberately no abraiding. One pin
,
wrapped 2 separated loops of 0.02mm insulated wire around as a precise
separator.
2 hours ago wixed with the hardener and placed between the spaced crossed
pins, held with a wooden clothes peg , holding force about 0.5 Kg.
I just tried measuring resistance between pins. Did not think , in
advance,
about soldering fine wire to the pins for ohms testing. Connecting 2 croc
leads to the crossed pins, still with clothes peg, resistance varied
between
3 and 35 ohm , holding in fingers. Highly sensitive to slight forces in
semicured state.
Will let it cure until tomorrow and retest conductance and also peel/sheer
strength of the epoxy. To be continued

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/



Minimum resistance about 200 ohm, shear or peal strength ? was 90gm at 13mm
distance to shear the joint.
Proportions were something like 2 Ag paint:1 hardner:1 resin , so perhaps
4:1:1 would be better and also newer product preumably. So for CMOS type
currents application not car windscreen heater repair use


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/