What's tips/tricks you have found to keep ultra low arcs stable (and/or even start)?

I was messing around with some box cutter blades today, welding them edge to edge and found it difficult to maintain a ~5amp arc. After rubbing the tungsten on some 320grit sand paper to really make the tip shiny, it helped a lot, but the arc would still wander, and was difficult to start without burning through - unless - filler rod was left past the joint, then allowed to melt/ball up to the joint, then the excess material would absorb the heat and allow the weld to continue.

Here's utility blades I welded about 4yr ago, and box cutter blades I tried today. Both times I used a #17 TIG torch with 3/32" tungsten, and shined the tip up a bit with fine sand paper after sharpening. The box cutter blades were far more difficult, and I found my hand isn't as steady as it was just 4yr ago Not that it's really a usable/practical talent, but after practicing this, going to .065" butt welds stainless is a breeze!