--- In Homebrew_PCBs@y..., milwiron@t... wrote:
> At 07:44 PM 06/11/2002 EDT, you wrote:
> >Denny: I ordered one "to play with", too; thinking, for THAT
price, no
> >biggie either way. Was curious about the "Sioux" model that costs
nearly
> >twice as much in same catalog, thought. Wonder if that
is "noticeably
> >better"?????
>
> Hi Jan,
> Like most industrial tools I suspect similar die grinders by
Dotco, Sioux,
> Nu-Line or Foredom are substantially better, though they do cost a
couple
> hundred bucks more. I have tools by Sioux and Foredom/Engis in the
shop,
> you can't kill 'em with a stick. The Enco seems to be a decent
value for
> the money so I'll give it a shot for starters. Unlike my Sioux and
Foredom
> tools I don't expect to see the Enco grinder still working daily in
my shop
> in 20 years. ;-)
> It would probably be worth keeping a spare Enco on hand and/or
making a
> universal V-groove mount to accept a better quality grinder in the
future
> if it were needed.
>
> >Clippard makes some super-fine electropneumatic valves, and those
coupled
> >with their piston-actuated two-way valves might make it possible
to turn
> >on/off the air except when this thing is "going down" for a hole.
>
> Adding a solenoid valve to the mill is almost a given anyhow, I
think
> you've got a good idea shutting the grinder down whenever possible.
There's
> very little rotating mass so spool time is very short.
> Denny
Denny: Just got in the Enco 1/8" "air Die Grinder" with VERY nice
1/8" collet, precision collet-nut and nose, and cloth braided O.D.
air-hose with flexible muffler over that. Runs VERY fast, and
exhaust is out the top, but without the muffler-tube over the hose,
it is very noisy! Eats air! The average 3/4 hp compressor would
probably run more than 50% of the time, if this thing was left on,
with nothing else using the same air. I only played with it "out of
the box" a minute or two, and it gets rapidly warm in half nearer the
collet, so I guess it needs some 3-1 oil squirted down the air-hose,
first. We'll see. I have no immmediate application, as my PCB-
drill has that 400 Hz, 12,000 motor, but looks like this might work
if a cleverly-machined hardened/ground shaft-jacket were machined
over it, and it then used in a linear ball-bearing arrangement.
Else, it would have to be mounted in a kludge with linear bearings,
etc. The alum. body is 15.5 mm (0.610"), so would take some work to
use it in a linear ball-bearing mount.