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Ray L. Volts
 
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Default Need Advice How to Repair Plastic Power Switch on Dell 19" Monitor


"spippy71" wrote in message
...
Hi,

Recently purchased a monitor from eBay. It's a Dell 19" Monitor model
P991 - Sony Trinitron. The monitor was dropped by the courier, and did
some damage to the power button. I've opened the monitor to have a look
and. Exterior button and spring are fine. It's the internal switch that
is damaged. The plastic arm broke away from the switch shaft. The switch
is is soldered onto the "D" board. The Exterior button pushes the arm,
which turns the switch on/off.

Anyone know the best way to reattach the shaft to the switch? Which glue
or cement would work best on these two plastic parts to make a solid bond?
I can post pictures if necessary.

Thanks,
Steve.


If it's a feather-touch control, then a cyanoacrylate will do. The best
1-part cyanoacrylate for plastic, IMHO, is called Plastic Surgery. This is
made, as the name suggests, especially for plastics -- it has a bit of
solvent in it which bites into the material, unlike garden-variety Super
Glues. I used to only find this at Walgreens, but it's been a while, so I
dunno who might stock it now.
There are some good 2-part cyanoacrylates (1 part is an accelerator). These
set up very fast, but Plastic Surgery performs as well as most 2-parters.

If, otoh, the plastic is under more stress, as with a high-current power
switch (cuz ya use more force to push it), you need a less brittle adhesive
for a lasting repair.

A really great product, albeit somewhat esoteric, is called Plas-T-Pair by
Rawn. This is a two-part, resin-based system -- you mix plastic powder with
a solvent and form up the compound. This stuff is perfect for damage where
there's missing bits of plastic, as you can make it as thick or thin as you
like and mold it into whatever shape you want while it's curing, after which
it can be drilled, filed and sanded to match the original part's shape. I
use the liquid solvent by itself for quick welds where the parts meet up
perfectly and there will be little stress on the piece. Where greater
strength is needed, I mix it up and leave a sheath of Plas-T-Pair around the
part in question.

Another specialty solvent I use is called Pro-Weld by Ambroid. It's a 2oz.
bottle of liquid with brush built into the cap. It bonds Styrene, Butyrate,
ABS, Acrylics, etc. This solvent creates solid joints and it sets up super
quick.

For future reference, just in case you dig into a piece of equipment where
you might need to repair a nylon part, forget it! I have yet to discover a
solvent that will work on nylon gears and the like. You might as well try
to weld teflon together. About the only thing available for these is tape.
I know there are some surgical-grade products that claim they work on Teflon
and Nylon, but I'll believe that when I see it.