I have never had much luck in using Helicoil thread inserts - even
when I used a kit. Now I am trying to do so without buying a kit.

I am trying to install (1) 1/4-28 thread insert. Because of a
relatively thin wall condition, a thin wall solid thread insert is out
of the question (my prefered solution for thread inserts). About 15 -
20 years ago I aquired a strip of 1/28 thread inserts (brand unkbown).
So I figured that I would buy a 1/4-28 thrd insert tap from McMaster-
Carr and fumble thru getting the one thread installed (and have the
tap available to use in the future).

No luck in fumbling thru with it. I tried to twist the insert to
reduce the OD, I tried to deform the end of the insert to make it
undersize, I tried to install the insert backwards, I threaded the
insert on a short 1/4-28 SHCS to use as an install tool. Looking in
the McMaster catalog, I see that the installation tool for the 1/4-28
is a winder style to reduce the OD of the insert for $32+. For those
of you who use these regularily and know what you are doing - advice
please. Obviously, I am not overly interested in spending more money
to install one insert.