Its enamel so probably something like Xylene so long as you only dip the leads.
But its often easier to just use a razor blade or sandpaper to scrape/remove it.
Thanks! sand paper sounds right. I'll try that. A little searching reveals that the copper is laminated some with clear and other like we get in the kit with red. Solvent may or may not completely get rid of the coating and sand paper with give good adhesion for the solder.
The coils came with quit a bit of length beyond the coil it self 6 inches or so on some of them and some are tinned with solder and some not. I will likely trim them a bit to minimize the size of the board.
I'm wondering, I assume it best to tin before twisting as that's the way the coils came or should I, once stripped just tightly twist connection then solder. The confusion comes when I hear in the videos, "solder is not the connection the twist is".
One final question, for the moment, will I affect the resistance by trimming a bit off the leads of the coil?
sorry for all the noob questions.