Re: Removing glued SMDs

On 29 Jan 2025 12:39:08 GMT, Roger Hayter <roger@hayter.org> wrote:

On 29 Jan 2025 at 12:29:57 GMT, "legg" <legg@nospam.magma.ca> wrote:
>

On Wed, 29 Jan 2025 11:41:20 +0100, HW <none@no.no> wrote:
 

On some boards, the SMD components are glued down prior to wave
soldering.
 
What is the best method for removing these parts, preferably without
damage?

 
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.

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