>I have tapped into foil and repaired it a few times. Scrape off the plastic
>to expose the copper (razorblade), be careful, don't go at it too hard. Wipe
>down exposed copper with alcohol. Tin your wire "jumper(s)" and use a good
>iron. Don't dick around, if the solder doesn't flow quickly stop and clean
>area again.
>
>I have used 20-22 gauge Teflon insulated, tinned copper wire. You have to be
>careful not to let the wire pull on the foil, restrain it in some way, I've
>used a spot of RTV silicon to locate and secure the wire.

Alistair's advice is good. Clean the copper well, tin your wire before you
make the connection, and work fast to avoid overheating the traces.
A small tipped, very hot (800F) soldering iron is good.

I would be cautious about the RTV though. Regular RTV contains
acetic acid, which corrodes copper. It's not a good thing to seal
bare copper connections with. I've seen connections sealed in RTV
that were totally green and crumbly after some years.
You can buy special RTV for electronics use, but it's rather more expensive.
For sealing small connections, a couple coats of nail polish works well.
Nail polish is also great for marking parts and electrical connectors.
It's cheap, comes in a zillion colors, is pretty durable, and cleans up easily
with acetone.
I have all 10 colors of the electrical color code in my tool box. (-:
(black, brown, red, orange, yellow, green, blue, violet, gray, white)

Steve

>Alistair
>
>
>--
>'82 Westy -> diesel converted to gas in '94
>albell@uvic.ca
>http://members.shaw.ca/albell