I'm not a fan of butt splices for inline cable modifications. I'll admit, they are less prone to failure, but I prefer inline straight solder splices. To compensate for the strength loss, I cover each soldered wire splice with a tiny piece of shrink wrap and then cover the entire splice with larger shrink wrap. Makes for a neater looking splice with a diameter only slightly larger than the cable itself.
Making these straight solder joints on fine wire is definitely a challenge. With my big fingers, it wouldn't be possible without a good "third hand" solder board.
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