One of the machining magazines I get had a picture of a mill using the
LN2 fed through the center of the tool with a special attachment
something like what you use when you don't have through the spindle
coolant option. I forget which one.
On 03/21/2011 12:08 PM, Bob La Londe wrote:
The machine is mostly made of aluminum with some steel parts.
Why? I use flood coolant on a mill that is steel and cast iron, and
have had no rusting or other problems with it. I use Encool from
Engineered Lubricants, it is totally amazing stuff, and I highly
recommend it. No relation other than a satisfied user.
Because the manufacturer of the Metal Nibbler One says, "ABSOLUTELY DO
NOT USE WATER BASED COOLANT ON THIS MILL." Aluminum is a very reactive
metal and the majority of this machine is aluminum. (Metal Nibbler Two
is about 95% aluminum.)
The short answer. "Cuz I ain't gonna."
I am not going to wash either of my little mostly aluminum mills down
Did I mention that there is a cult following for water coolant guys
almost as strong as the "WD-40 should never have been invented" cult.
I will most probably use a water soluble coolant on the Hurco when I get
it going, but its 100% cast iron and steel. Not an issue amazingly
enough for an iron and steel machine.
The following rant is not directed at any one individual:
Water is a no go for Metal Nibbler One or Two. So, given that I
absolutely will not use a water based or water soluble regardless of how
stupid I am and how smart you are and how superior water based coolants
are and I'm to dumb to know any better I still ain't gonna, do you have
good experience and recommendations with/for other options for milling
That would indicate an ignorance on their part of what's available in
water-based coolants today.
I know some little bit about the reactivity of aluminum (being in the
pyrotechnics business). Its reactions with water are a matter of
constant attention in my line.
Simply by adjusting the pH of an otherwise non-corrosive water solution
with a suitable buffer, one can reduce the reaction potential to nil.
Most modern coolants contain such buffers, and are specifically designed
for certain metals. Many are designed not only to not injure, but
specifically to benefit the life and surfaces of aluminum parts.
I'd add that if a mill is designed to suck water up into the motor during
use, it's badly (no, I'll say stupidly and negligently) designed.
I will research this "Metal Nibbler" thing. I want to know what to
On 3/21/2011 11:55 AM, Lloyd E. Sponenburgh wrote:
LOL. I never typed a single word about it sucking water up into the
motor. I did type that it moves a lot of air in a previous post. Its
not the original piddly little 10K spindle either. This is a 30K
spindle. I did express a negative about putting any flammable mist into
the air in the presence of a brush motor. (one mfg uses ethanol as
referenced in my original post) That comment has absolutely nothing to
do with any type of flood coolant water based or otherwise, but
interesting that you picked that out for some reason and misapplied it.
If it moves air out one end, then by default air must move in the
other end. Bad news for a flammable coolant mist.
Metal Nibbler and Metal Nibbler Two both bare little resemblance to
their original forms at this point.
As to water based coolant. Again, I'm just not going to use it on my
aluminum body machines. Maybe someday I may change my mind, but not in
the forseeable future.
So purely as an intellectual exercise... assume that water is 100% not
available in any form. What would you use as a cutting
coolant/lubricant for milling aluminum.
As to seeking out this "Metal Nibbler" good luck. For a hint you might
bear in mind that I call the Hurco mill Metal Nibbler Three.
I did reread my post. A mist drawn in might cause an explosion if a
flammable coolant was used, because a brush motor "will" have sparking.
I guess I needed to spell it out more thoroughly. Figured most people
would get that.
I can see though were it did look confusing.
Here's what you wrote, after saying water-based was not satisfactory:
"There is a lot of air moving just from the spindle motor, and
there is a potential for sparks if a mist gets drawn into the motor."
The premise was stated that mist being drawn in would cause sparks.
The fact was that sparks are always there, and flammable mists are not
good. That ain't what you wrote. It isn't even close. You implied that
the mist would _cause_ the sparks.
"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote:
Just a techie nitpick - commutator brushes produce "arcs" - "sparks" are
the things that a grinder makes. (although if the arcs melt or vaporize
the commutator or brush material, the flying glowing things would be
(possibly interesting to note - my automatic spell checker doesn't like
"commutator" or "vaporize.")
I suppose your car has "arc plugs" then? How about spark-gap transmitters
and switches, are they misnamed? What about the Merriam-Webster dictionary?
"2 a : a luminous disruptive electrical discharge of very short duration
between two conductors separated by a gas (as air) b : the discharge in a
spark plug c : the mechanism controlling the discharge in a spark plug "
If there is any difference, "spark" usually refers to a transient discharge
and an arc is sustained.
Why do you insist on posting so much crap in such an authoritarian manner
when in fact you have no idea?
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