While I myself do not follow the practice of using tig rod to pin turnbuckles... I know you can use the same tools and techniques as when working with cotter pins. Perhaps a pair of pliers would assist a set of dikes to complete the task. Tune the rig, hold a piece of rod up across both cotter pin holes and judge the length needed. Cut and then bend (pliers) one 90* bend leaving the short leg something like 8:1 for diameter of tig rod, I suppose. hole the thing up again, judge the position of the next bend and use those pliers stick your c in the two holes and use the dikes, or pliers or whatever, to roll the end up into the body of the turnbuckle. I suppose I could do that, but then I’d have to carry a rod box in addition to a cotter pin box, because I’d still need those. Less of them.
... but anyway that’s about as much as I'll say about something I haven't actually tried. ( IIRC
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