The first step in
board assembly is to
populate the PCB.
should be installed from
smallest (shortest) to
largest (tallest). For
components, I find that the foam
compression works best for low-profile parts
such as resistors, diodes, and DIP ICs. In this
case, position the jig with knobs down and
install the PCB with the component side
facing up as in Figure 7. For maximum
strength, the long side of the board should
be oriented parallel to the support rails. After
placing the components, clamp the foam
plate in place and turn the jig over for
soldering (see Figure 8).
I was initially concerned that heat from
the soldering iron would melt the
polyurethane foam, but so far this has not
been a problem. For larger components, I
tend to either use a non-conductive
superglue or bend the leads slightly to keep
the parts in place while upside down. Glue is
also helpful with SMT components, even
though placement and soldering is
done from the same side.
Some components just don’t
work well with any of the
techniques. This was recently the
case with a certain terminal block
that I was using. It was too large to
be clamped with foam, had leads
that were too short to bend, and
didn’t respond well to superglue.
As shown back in Figure 1, the
rotating side supports help with
these situations. A small amount of
solder is first applied to one of the
component’s holes in the board.
Then, with the component in one
hand and the soldering iron in the
other, the solder plug is melted as
the part is inserted. The other pins can then be soldered
C'SINK FOR 1/4" FHCS
FIGURE 5. Side
■ FIGURE 6. Foam compression plate detail.
■ FIGURE 7. Circuit boards in position for component placement.
WHERE TO GO
I spent about $80 on the parts for this jig. To me, it
was a very worthwhile expense considering the number of
boards I assemble and the quicker workflow that it
provides. A hobbyist might find the cost excessive, but it
could be built for significantly less depending on your