IME, for a meter hole, the cut doesn't have to be all that 'clean' anyway,
just reasonably round. The meter face will cover up most imperfections. Of
course, there's the personal satisfaction of making a nice, clean hole
(which you may be the only one to ever see).

jak

"Roger Halstead" wrote in message
...
On Tue, 28 Oct 2003 20:55:41 -0600, Biz WDØHCO wrote:

in article , Michael A. Terrell at
wrote on 10/28/03 7:38 PM:

Biz WDØHCO wrote:

After 31 years and a bunch of parts in the garage, I am finally
building my
dream CW receiver from scratch.

Just wondering if I converted the 6.3 VAC filament voltage to a DC
voltage
if doing so would be worth the effort to reduce hum.

Opinions ?

Also I would like to cut a round 4" diameter hole in the 1/8" aluminum
front
panel for the speaker grill. Is there a way to do this without a
Greenlee
Pneumatic punch? I have a jig saw which I can cut square holes but
round
holes are another matter. Is there a better way? I can drill round
holes up
to 7/8" with a unibit but I think 7/8" is as big as they get.

Thanks

Biz - WDØHCO

Do you have a good drill press? You can buy either a 4" hole saw, or
an adjustable cutter that drills a pilot hole, then uses a lathe tool
to
cut a clean hole in the metal. They cut a fairly clean hole, but the
metal has to be clamped down, and the tool has to run at a low speed.

Why yes I do and I can change speeds on it.
But I thought those hole saws where for wood only.
BTW Aluminum panel is pretty soft so this might actually work.
Do they make hole saws for metal?

As Michael has said they do make hole saws for metal as well. It does
take a "rugged" drill press though to keep the saw cutting a nice
clean hole.

Saw a gizmo called a "fly cutter" used on a drill press to cut holes.
It looked pretty dangerous.

The "Fly Cutter" is a great tool for cutting clean holes. I'd much
rather use it on a milling machine though. And...yes, it does take
some precautions and it needs to run pretty slow. Course when cutting
metal the number of teeth per inch depends on what you are cutting as
does the speed. Most drill presses run a bit fast even at their
slowest speed for cutting metal, but mine seems to do OK, although it
grabs like crazy when breaking through

And use the proper cutting oil to help keep the teeth from clogging
and the saw from binding. Use some good, flat clamps so the piece is
held rigidly. It shouldn't flex, no move in any axis. I've had the
pleasure...and embarrassment of having a big drill bit take a pretty
hefty chunk of aluminum away from me and then start slapping the
column with it. This was in a machine shop. I hit the power switch
and dove...There wasn't one person standing up until it got
quiet...very quiet...then all you could see were eyes peaking up over
the benches. Each one afraid of what they might see.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)


I think that's what you are talking about.

Looks like a trip to Sears is in order!

:^) Biz WDØHCO