How are you managing coolant spray on your CNC knee mill?

The work on the KMB1 is progressing with most things figured out and
my largest limitation being time available to work on it.

I'll be adding a full separate Z to the side of the head for a 40K
watercooled spindle.

I also plan to machine some stuff that with mounting hardware will
exceed the size of the table.

On Mon, 12 Nov 2012 09:42:57 -0800 (PST), Bob La Londe
wrote:

How are you managing coolant spray on your CNC knee mill?

The work on the KMB1 is progressing with most things figured out and
my largest limitation being time available to work on it.

I'll be adding a full separate Z to the side of the head for a 40K
watercooled spindle.

I also plan to machine some stuff that with mounting hardware will
exceed the size of the table.



I don't use flood on my CNC because of the mess. I did make a copy of
the Henchforth fogbuster mister for a heavy coolant spray.

if you're cooling that 40 K spindle you'll need a nice set of splash
guards. I guess the size would depend on how big your parts are.

Karl

Bob La Londe wrote:

How are you managing coolant spray on your CNC knee mill?

Here's one of my shield setups :
http://pico-systems.com/shield.html

But, if the part is much larger than the table, you may have to
enclose the whole machine, not just an area on top of the table.
But, this setup I made can handle larger parts if they are spaced
above the table, because the front and back tilt outward from the
Tee slots. The sides could be made to do the same if you need
that.

Jon

"Jon Elson" wrote in message
...
Bob La Londe wrote:

How are you managing coolant spray on your CNC knee mill?

Here's one of my shield setups :
http://pico-systems.com/shield.html

That gives me some ideas. One thing I was thinking of is maybe some small
shields on slide lock rods that are mounted on the head. This should knock
down the most energetic spray at the source, and then do a box around the
table for any excess spray. Sometimes seeing other people's solutions is
just what you need to get your mind going in other directions.

But, if the part is much larger than the table, you may have to
enclose the whole machine, not just an area on top of the table.

I have been thinking about that as a possibility. To do a really good job
would be a bit involved. Not the biggest box I have ever seen, but a pretty
large box would be needed. I might have to either remove my electronics
from the machine, or be a little more proactive about air conditioning them.
The box itself would be interesting enough. Perhaps front and side
removable shower doors, but then seal the floor and cut a sump through the
concrete.


But, this setup I made can handle larger parts if they are spaced
above the table, because the front and back tilt outward from the
Tee slots. The sides could be made to do the same if you need
that.

Thanks Jon. I was leaning towards an aluminum frame that sets in but
extends out from the table on the front and sides with slide in plexi
panels. Might even give vacuum forming a shot to put an inward angled spray
lip on the plexi glass. Either that or just call Ace Acrylics and let them
do it. LOL. Pair that with moveable spray shields up close and it might be
ok.

"Karl Townsend" wrote in message
...
On Mon, 12 Nov 2012 09:42:57 -0800 (PST), Bob La Londe
wrote:

How are you managing coolant spray on your CNC knee mill?

The work on the KMB1 is progressing with most things figured out and
my largest limitation being time available to work on it.

I'll be adding a full separate Z to the side of the head for a 40K
watercooled spindle.

I also plan to machine some stuff that with mounting hardware will
exceed the size of the table.



I don't use flood on my CNC because of the mess. I did make a copy of
the Henchforth fogbuster mister for a heavy coolant spray.

if you're cooling that 40 K spindle...

Oh, yeah. without some form of coolant it would just be an exercise in
removing aluminum flavored chewing gum from the flutes.

you'll need a nice set of splash
guards.

I was thinking of maybe some form of moveable/ positionable splash and spray
guards up close to knock down and reduce the inertia of the worst of it, and
then a biger "enclosure" of some kind on the table. As mentioned in my
reply to Jon I have thought about the practicality of a full enclosure on
the machine as well, but I think that is mostly wishful thinking as a fairly
expensive and involved project in itself.

I guess the size would depend on how big your parts are.

I have two types of projects in mind for this machine. Some lower speed
stuff would be large, and the high speed stuff would mostly be sub table
size.

Bob La Londe wrote:

"Karl Townsend" wrote in message

if you're cooling that 40 K spindle...

Oh, yeah. without some form of coolant it would just be an exercise in
removing aluminum flavored chewing gum from the flutes.
Well, no, actually high speed machining is usually done dry. The
poor application of coolant to a spindle turning that fast leads to
the cutter heating up and then getting a splash of coolant, and that
causes thermal shock to the cutting edge. Better to just let it get
hot and stay hot. But, you take a lighter cut and move the cutter
past the work as fast as you possibly can to avoid heat buildup in
one area. The bulk material and the chips carry away most of the
heat. I read a book about it, the test case was at Boeing, doing
wing spars. They were running a 75 Hp Cincinnatti spindle at
80K RPM with a 1/2" solid carbide end mill! Feedrate was over
100 IPM (I forget the exact number) and they were removing 640
cubic inches of metal per minute. This was run dry.

Jon

"Jon Elson" wrote in message
...
Bob La Londe wrote:

"Karl Townsend" wrote in message

if you're cooling that 40 K spindle...

Oh, yeah. without some form of coolant it would just be an exercise in
removing aluminum flavored chewing gum from the flutes.
Well, no, actually high speed machining is usually done dry. The
poor application of coolant to a spindle turning that fast leads to
the cutter heating up and then getting a splash of coolant, and that
causes thermal shock to the cutting edge. Better to just let it get
hot and stay hot. But, you take a lighter cut and move the cutter
past the work as fast as you possibly can to avoid heat buildup in
one area. The bulk material and the chips carry away most of the
heat. I read a book about it, the test case was at Boeing, doing
wing spars. They were running a 75 Hp Cincinnatti spindle at
80K RPM with a 1/2" solid carbide end mill! Feedrate was over
100 IPM (I forget the exact number) and they were removing 640
cubic inches of metal per minute. This was run dry.

Jon

Ok, so show me an example of doing that with a .03125 cutter?