CHAPTER 23 ■ THE MOTHERBOARD
I prefer clear silicone adhesive for gluing components to circuit boards (see Figure 23-8). Many
adhesives simply don’t stick well to the resin circuit board substrate. Silicone adhesive is a tacky gel, so it’s
easy to apply exactly where you want it, it stays put, and keeps the part from sliding around too much before
it is dry. Actually, because silicone adhesive doesn’t dry instantly, you can still shift or nudge the part if your
initial placement wasn’t accurate.
Figure 23-8. DAP clear silicone adhesive with a toothpick for applying
Additionally, silicone adhesive can stand high temperatures, which is a good idea for anything that
holds a part to be soldered. Silicone adhesive dries to a rubbery consistency, so you can peel it off if the
component needs to be desoldered.
- Reinsert the headers into the desired location on the board.
- Let the adhesive dry for five minutes (or whatever time period is instructed on
the package). Don’t solder around adhesives that may still be expelling fumes or
that are listed as flammable!
Bending Component Leads
Fortunately, most component leads are much more pliable than the rigid metal pins of connectors. Leads
can be bent to hold the component in place so you don’t need to glue them.
- Carefully bend the component leads toward the back of the board so that the
components won’t fall out during soldering (see Figure 23-9). Bend the leads
only as much as necessary to keep the components in place during soldering;
don’t bend the leads completely flat against the board. Solder tends to wick
under the flattened leads and contact other pads or components. Also, it’s more
difficult to trim off excess length of flattened leads.