Broken tiny tap in aluminium

[Dr Stan]

(09-08-2016, 04:40 AM)Mike E. Wrote:

(09-07-2016, 02:58 PM)Dr Stan Wrote: ................. The best cutting compound I've ever used for tapping in aluminum is pork lard. ...........................

" Lacquer Thinner " used as a cutting fluid in tapping aluminium will produce perfect razor sharp threads; also, it evaporates quickly leaving a clean hole. I've used it with fine results on tapping holes as small as 2-56 tpi.  Learned this trick from a machinist at Lockheed aircraft back in the 1970's. Try it.

Thanks for the info.