Those crimp-on terminals are very inexpensive when purchased in bulk.
As for lead/tin solder suitability .. solder well .. then coat the
terminal with silicone seal [RTV if you can find it] and you won't have
to worry about contact with typical earth or weather.
I am also looking for ring terminals suitable for ground radials,
something less expensive than insulated crimp-on terminals, for 1/4'
studs and multiple #13 wires. I also wish information about using
various solders outdoors. Is it correct that lead-tin solder is not
suitable if in contact with typical earth? How about near earth,
exposed to weather? Is ph of the earth a factor? What is recommended?
73 de WOØW