This brings up the question, what's the best material for probe tips? Assuming cost is no object, you want them to stay sharp for a long while and not oxidize. Ideally they'd have low thermal emf to copper, but that might be a lot to ask. I'm thinking one of the hardenable stainless steels like 420, 430 or such. Tungsten? Pure tungsten welding electrodes are easily available. Other ideas?
Fluke probes I have have tips made from stainless that is just slightly ferromagnetic. That means some sort of austenitic stainless ( that would be 300 series in US ).
I have had them for 20+ years, and i did touch up tips once. Only once. That makes them tough enough.
I guess for maximum hardness, you could make tips from tungsten carbide... Sharpening and reshaping PCB drills and routing bits should be easy enough with diamond wheel grinder.
But they would be prone to chipping and breaking if dropped on hard surface....
For modular probes, with no cable attached, you just put them in a drill, and pull across sharpening stone or a abrasive paper on a glass at angle while rotating them.
That takes care of tip if it was a bit deformed.. If it is a lot, you will need to reshape it.. All the same, more time...