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Re: Resistance Leak from Fast Track turnouts
I am tempted to get some of this silver bearing solder to try out. I have a lifetime of experience with 60/40 Tin Lead solder and have no problem getting good joints.
Pre-tinning ties will greatly help in soldering them to your rails. The trick is keeping the thickness of the tinning down. To that end I buy pre-tinned ties. I created and contracted to have the ties made at a PCB plant in China. Pre-tinned, drilled and gaped ties make my life a whole lot easier (www.voltscooter.com).
Two things are required when soldering large things like rails and ties. First your iron most have sufficient wattage to support the flow of heat from the iron to the rail. Forty watts is sufficient IMHO. Second the iron tip needs have enough heat capacity to quickly heat up the rail before there is enough time for the heat to flow down the rail and overly melt the plastic ties. The tip of the iron should be as large in volume as you can get for the iron you are using. Lack of a large tip can be somewhat made up for by increasing the tip temperature. Increasing the tip temperature requires experience so that the solder job is completed quickly. Doing a joint quickly requires sufficient flux to clean the rail quickly. A paste can help this process but is not required if you use good technique and a good rosin core solder. The things being soldered need to both be in contact with the tip and the point of contact needs to be solid and as broad as possible to assist the flow of heat. There are lots of sites out there to provide more rudimentary soldering instruction.
Set up someplace to practice what you are doing before you tackle jobs on your layout.