but they are twisted together and secured with some sort of mechanical fastener (not a wire nut) that I don't want to disturb. Is there some sort of small clamp that would serve the purpose of ...

Fortunately [Max Egorov] reminded us of DIY wire clamps (video after the break), an excellent alternative that is very effective, covers an infinite size range and is easy to make with a simple tool.

RONKONKOMA, N.Y.--(BUSINESS WIRE)--Qosina is pleased to stock a variety of Oetiker ® stainless steel, non-greased StepLess ® ear clamps that can be used in a wide range of applications across ...