Mark Lloyd wrote:

What if you have a copper feeder, and TWO stranded wires?
..
Doesn't sound like that much problem. I use wire nuts with a 'live
spring'. The spring doesn't have plastic right behind it and deforms
over the wires making a more secure connection (IMHO). If you take a
wire nut off that has been tightened you can see the deformation. (Far
as I know these don't exist in a size smaller than yellow.)

Use wire combinations the manufacturer indicates are in the capability
of the wire nut. As suggested elsewhere I extend stranded wires slightly
past solid.

IMHO 2 #12 solids and a stranded #18 is a bigger problem - the #18 can
sit in the 'valley' between the solids. I twist the solids and keep the
smaller wire straight.

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