Removing glued SMDs

Unaware of one.

Remove to replace only.

RL

Expensive or proprietory chips are regularly removed from donor boards with a mixture of hot air, flux and perhaps LMP solder, for reuse. But I agree no one is going to reuse a resistor or capacitor.

Most of the adhesives used for this soften at solder-melting temperatures, so the parts can be fairly easily removed with hot air.

For large components, or less heat-sensitive underfill materials (I'm looking at you, Apple...) some scavengers have had success using a mill to grind away the PCB (for scavenging the part from a scrap board) or the part itself (for removing a failed part to replace it). Obviously, it's important to get the PCB exactly level to the milling plane, and precise depth control is critical.

Epoxy dhesive is used on wave-solderable SMD assemblies, to prevent parts being swept away in the wave process, or in subsequent reapplication of reflow processes.

There is a body size, pinspacing limitation that prevents most complex/costly parts from this manufacturing technique. Consult your part vendor if in doubt.

The epoxy adhesive used, once cured, will not be degraded at a later time by temperatures provided by hot air and bonds stronger than most IC packaging material fracture stress limits.

RL