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PRE-SOLDER
ADHESIVE ATTACHMENT OF COMPONENTS - STOP CHASING PARTS AROUND
THE BOARD !
STREAMLINE HAND SOLDERING: When hand soldering a common
difficulty is trying to keep the part in place while you get at
least one solder joint started. While it is possible to build
circuits without using adhesives, Many users have found that attaching
the parts first and then performing all the soldering operations
"two handed" is easier and yields good results. A great
many adhesives for this purpose are on the market, and many come
with small blunt needle applicators that permit precision placement
of glue dots. In other cases adhesives or epoxies may be applied
by the pin transfer process.
PIN TRANSFER OF ADHESIVE: When the adhesive is supplied
as a bulk liquid a means to apply a small dot is needed. The pin
transfer method is simple and easy. Straighten a paper clip or
use a piece of rigid wire as the pin. Place a small puddle of
adhesive on a flat surface a dip the pin and then simply transfer
the adhesive to the board surface. In this case factors such as
depth of supply puddle and viscosity of the adhesive, as well
as surface tension will determine the results. Practice is essential!
WHAT IF
I DON'T HAVE SPECIAL ADHESIVE: A number of users have achieved
acceptable results with common two part epoxies found in hardware
stores, as well as thick gel type cyanoacrylate adhesives. It
is important to understand that commercial products made for Surface
Mount attachment are usually formulated to provide for enhanced
matching of temperature coefficients, thermal conductivity, contrast
enhancement, reworkability, etc. As a practical matter, from a
technical purists perspective if would be best to have the special
SMD adhesives, however, other adhesives could be used on a limited
basis for prototype work within the limitations that may exist.
Obviously a material must be selected that is non-conductive and
will be of sufficient strength to withstand the effects of careful
soldering.
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