I've been winding a guitar pickup and occasionally there will be knots in the thread of enameled wire from my spool. Some of them are loose enough that I can untie them, but there are some really tight ones that if I were to try and pull the ends apart, the thread would break and I would have to start my process over.
My assumption is that, given that a pickup is usually a couple thousand feet of wire, that one or two few-inch knots in the loop are negligible - that they would add some unwanted resistance and/or leakage current(?) but wouldn't be enough to impede current from driving through the loop when the guitar strings are plucked. But I'm not actually sure.
What are the effects of having knots in a solenoid or wire loop?