Some of my personal observations from my wrench twisting days. They make a tapping/cutting oil for aluminum but you can also use wax, you do not want to use regular tapping oil, it will cause more problems then going with no lube. Walmart and Dollar stores sell cheap tea candles in the little foil cups, I found some of those are a very soft wax that you can press a thumb into and those work best, for me....

I also found with small taps, make no more then a turn and a half, back out, blow chips out of the hole and off the tap, rub wax on the tap again and repeat until you get the depth you need. Slow, easy, keep the chips clear and keeping the tap lubed has better chance of success, but every now and then it happens, SNAP.....

Oh yeah, old, worn & dull taps are temping to use but your better off throwing them away and getting a new one before Ole Mr. Murphy comes calling, again....