On Mon, 11 Apr 2016 19:15:33 +0700, John B.
wrote:

On Sun, 10 Apr 2016 09:02:01 -0400, Ed Huntress
wrote:

On Sun, 10 Apr 2016 05:41:08 -0700 (PDT), "
wrote:

On Saturday, April 9, 2016 at 8:17:32 PM UTC-4, John Doe wrote:
whit3rd wrote:

If you have a well-lit bench

I have the best possible lighting, always and everywhere

http://ecx.images-amazon.com/images/...L._SL1080_.jpg

I assume " no tools " really means no expensive tools. But even there I run into trouble. If I were doing it I would use a drill press to remove most of the material. And then would use some small files along with a machinists square to " file to fit ".

Dan

Do you have a machinist's square that will get inside of a 1/2" hole?
g

I think he's stuck with Tom's suggestion of using a jeweler's saw and
finishing with a regular fine-tooth triangular file, unless he has
chisels and coarse-tooth files made for aluminum.

One of the first suggestions the bloke got was "drill a half inch hole
and file it square".

Maybe 15 minutes of work.... if you have to look for the drill bit :-)

Rolls-Royce had an employment test for budding machinists. They gave
him a steel plate with a square hole and a round brass bar. The test
was to file the bar square on the end so it fit into the hole, with no
light visible when it was held up to a bright light. This was in the
early 1920s.

--
Ed Huntress