Dr. Anton T. Squeegee wrote:

In article , TRABEM
says...


Has anyone tried Masterbonds conductive epoxy for attaching SMT
components to a printed circuit board?

Seems like a great idea, especially if it works well::


Not really. Consider the angle of serviceability. It's easy enough
to use a 'HoTweezer' station to replace a bad chip component secured
with solder. It's darn near impossible to replace the same component if
secured with Epoxy.

Also, I'm not convinced that "conductive" Epoxy really is. I'd
want to see some real numbers on resistance per cm/squared on the stuff
before I even consider it for any sort of repair work.

Any job worth doing is worth doing right. If you're trying to
attach surface-mount components, invest in the proper
soldering/desoldering equipment instead of looking for impractical
shortcuts. It may cost more at the get-go, but it'll cost a lot less in
the long run.

Keep the peace(es).


The silver conductive epoxy is extremely conductive, and even tho i
never measuresd the resistivity, i would wager that it is better than
copper if used properly.

Robert Baer wrote:

The silver conductive epoxy is extremely conductive, and even tho i
never measuresd the resistivity, i would wager that it is better than
copper if used properly.

Here are some examples of silver epoxies:
http://news.thomasnet.com/fullstory/460221
10^-3 ohm cm

http://www.mgchemicals.com/products/8331.html
2*10^-2 ohm cm

http://bondline.net/datasheets/2072.pdf
4*10^-4 ohm cm

http://bondline.net/datasheets/2080.pdf
5*10^-3 ohm cm

http://bondline.net/datasheets/2111.pdf
2*10^-4 ohm cm

http://bondline.net/datasheets/2120.pdf
5*10^-3 ohm cm

Copper:
http://www.lehighton.com/AppNotes/Cu...llization.html
1.68*10^-6 ohm cm

According to these sources, copper is about 100 to 10,000 times as
conductive as silver filled epoxy.

Robert Baer wrote:

The silver conductive epoxy is extremely conductive, and even tho i
never measuresd the resistivity, i would wager that it is better than
copper if used properly.

Just another point of reference. From:
http://www.efunda.com/materials/solders/tin_lead.cfm
Eutectic tin lead solder has a conductivity of about 1.44*10^-5 ohm cm,
or 8.5 times that of copper.

I read in sci.electronics.design that wrote (in
.com) about 'epoxy
instead of solder?', on Thu, 6 Oct 2005:

Robert Baer wrote:

The silver conductive epoxy is extremely conductive, and even tho i
never measuresd the resistivity, i would wager that it is better than
copper if used properly.

Just another point of reference. From:
http://www.efunda.com/materials/solders/tin_lead.cfm
Eutectic tin lead solder has a conductivity of about 1.44*10^-5 ohm cm,
or 8.5 times that of copper.

resistivity, not conductivity.
--
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

John Woodgate wrote:
I read in sci.electronics.design that wrote:


Just another point of reference. From:
http://www.efunda.com/materials/solders/tin_lead.cfm
Eutectic tin lead solder has a conductivity of about 1.44*10^-5 ohm cm,
or 8.5 times that of copper.

resistivity, not conductivity.

Thank you.