In a message dated 5/14/02 12:15:11 AM, j_rodgers@CHARTER.NET writes:

<< The ease-out had a left-hand thread, sharp edges on the thread, and it't
pitch was extremely course, like maybe 1:3 -- one turn of thread in three
inches of length . Anyway, if the stud was drilled out sufficiently it was
usually not much more than a shell, and
the thread of the Ease-out would catch, and get a deeper bite as you turned
the ease-out counter clockwise. I don't recall ever seeing a failure when the
stud was drilled right. >>

John,

Spot on advice.  The thread, if it can be called that, of an easy-out, if IT
can be called that, has multiple starts so its course pitch (high helix, slow
twist) sometimes goes unnoticed.  Easy-outs can fail in the worst way (snap
off) if the pilot hole is not sized correctly or is drilled off-center.  As
you mentioned, a drilling jig is needed to do the job with any certainty of
outcome.  Otherwise, there is a risk of compounding the problem by ending up
with a piece of the rock hard easy-out embedded in the broken fastener.

Rich (aka Rico El Luchador por la Libertad)