At 10.43 2013.05.23, RussellMc wrote:
>>> There are neutral cure silicones, they don't use acetic acid.
>
>> Thank You Isaac. I read between the lines that acetic acid silicone=20
>use is a no-no?
>
>Standard advice  is that acetic acid cure silicone rubbers "must not"
>be used in electronic circuitry.
>It affects not only the in-contact area but releases AA which can
>corrode other components.
>
>Cheap neutral cure SR's are alkoxy  cure which is OK for most things
>but tends to corrode bare copper. There is usually not too much bare
>copper around.
>
>Most expensive and rarer SRs use a Methyl-alcohol only release cure.
>Volume released is enough to be worth ventiallting for in a production
>situation but is probably 'not too bad' for one offs.
>
>Acetoxy cure release both MA and other components.

Thank you Russel.. not much there into Mouser or DigiKey catalogs, if
it may be useful to anyone I report here the (apparently) best match:
http://www.digikey.com/product-detail/en/135264/1000-111-ND/2486659


>_____________
>
>SMD soldering - much on web and many here are far far far more expert
>than I re hand soldering but, contrary to hat may seem obvious, a
>large broad tip is superior for small resistor soldering.
>Tin pads if needed.
>Place resistor with contacts touching pads but located on the side of
>pads away from iron.
>Place broad iron tip on both pads at once so solder melts at about the
>same time om each and wave of melt will propagate across pad to far
>side where resistor awaits.
>Resistor will now pull itself into position.
>Any technology sufficiently advanced is indistinguishable from magic.
>In this case it's surface tension doing the magic.
>
>The resistor gets a relatively gentle ride as the hot solder comes to
>it and draws it into the hotter area.

Thanks for your insights.

Cheers,
Mario


>
>
>         Russell
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