I don't drill holes in my Atlas track. I first clean it with a Dremel wire brush. I then apply flux to the wire and the track. I melt some solder on both the track and wire. Then I solder them together. It takes a little time to heat up the track which I do before applying the wire which will have its solder liquefy faster. I clip heat sinks near the solder point so as to not melt the ties.
Alan