During tool change sequence, the machines obviously give an air-blast to ensure a clean taper, but is there an M-code to have it on as a coolant?
i.e. using a TSC tool and holder?

Im using this on a MIKRON to great effect, and wondered if i could transfer the success on HAAS machines.

Ginger, that would be cool, literally, but as far as I know there is no M-Code to trigger this on the Haas. I wouldn't mind seeing it as an option!!!!

Is this reasoning correct?

You would need air for using an air blast to clear chips.

This is not applicable to aluminum because with aluminum you really need lubrication and much more cooling than air can provide.

So you are probably using it for steel.

Which means you are not likely using really, really high spindle speeds.

Also with air you are not using multi-hundred pounds per square inch pressure.

So why not use a tool spindle nose mounted/holder mounted air inducer similar to what is available for through the tool coolant. As I understand it this is possible but is limited in pressure and rpm for coolant because it is difficult to get rotating seals that can handle high pressure at high rpm.

As always your reasoning is correct for me atleast. The thing with good quality coolant induced holders is $$ by the time you've paid for a few, you might as well have bought the option on the machine. The place I'm full time at found this out the hard way!!! I have seen some articles on then mikron machines have M code activated air through the spindle. Think of the benefits for High speed machining when finishing molds and such! and pocketing and on and on. You may never recut a chip again!!!!!!

....Think of the benefits ..... You may never recut a chip again!!!!!!

This is true; it makes a big difference. I have a somewhat hokey setup on my SuperMiniMill in my prototype shop. I connected an air line with a non-return valve into a tee in the coolant lines at the spindle and I have a coolant nozzle with a plastic tip that goes down as close to the tool as possible. This way I can have air or coolant and can switch between the two just by having a stop in the program so I can close a ball valve in the coolant supply and turn on the air. By carefully positioning the air nozzle I can get most of the chips out of an interpolated hole and only occasionally do I forget that if the nozzle is too close the toolchange eats it. Which is why I use plastic because the way it gets eaten is sometimes to get jammed in the taper.

In the main shop I have great plans to setup a similar air blast on some of the production machines running leaded steel. I even have a hulking great compressor to supply about 45 cfm separate to the regular clean and dry machine air but have not managed to squeeze out the time to get all the lines run.

Hi Geof,

Thanks for your input on this subject.

An M code would be nice but in my case I was just looking for a manually operated system to blow the chips away from time to time. I have a manual system that I used on my bridgeport that has worked pretty well and thought I would mount a air nozzle(s) in the area of the coolant nozzle(s) and have it actuated by either a hand or foot valve like the one made for Heinrich air vises. That way you wouldn't have to open the door to just give it a quick blast of air. Maybe you could even hook up some type of a relay to the chip auger and call for that in the program and run it for a programmed amount of time??? I wouldn't think that the chip auger on for a moment of two would be a big deal. I am new at this so that may not be possible.

Just something I was thinking about. Probably not much use in a high production environment but in my operation it may be of some use.

John

..... Maybe you could even hook up some type of a relay to the chip auger and call for that in the program and run it for a programmed amount of time??? ...... Probably not much use in a high production environment but in my operation it may be of some use.

John

Look in your manual on the topic of M Function Relays. It is in the Index, I checked.

And look at this thread, particular post #6. You can easily control a relay with an M code; we do it on several machines. You could have a push button mounted somewhere to give manual control also.

http://www.cnczone.com/forums/showthread.php?t=50357

hi all,

many of my tool holders have side inlet for coolant, have somebody try to deliver coolant thru this holes on machines that doesn`t have TSC ?

Hi Geof,

Thanks for the link.

John

the job im doing is in P20 tool steel.
Bore-milling dia'70mm x 81mm deep holes.
1000 rpm, and 3000mm/min.
at these rates with air Thro' the spindle, the chips really fly! and on first run, milled over 30 bores without changing/turning inserts.

in all honesty, i cant see our VF8's coping with that feed and speed, like our mikrons are.
but it may be of use in the future.

the majority of our tooling is heat-shrink that is all TSC.
have never had much success with collar fed TSC tools, so assume air fed the same way wouldnt be great either.

You could probably find the solenoid valve that controls the tool change air blast and tap into the line downstream of it with a solenoid valve controlled from a user M function.

But this might not be a good idea, even turning on the normal air purge might not be a good idea, because you do not know is the seal is designed to be pressurized while the spindle is running. I have had machines that fed air into the spindle when it was stationary and the seals were designed to retract when the air was off; they only extended and formed a seal when air was present under pressure. One time I accidently turned the air on with the spindle turning and the seals acted as a very efficient brake; and never did seal correctly after that.

Pit,

Those holes are fro machines that deliever coolant to the holders this way. If the machine doesn't have the option, it's pretty useless I believe as there is nothing that I'd want to put between the flange of the tool holder, and the spindle face!!!

Hmmm...

Have anybody tried this yet?

i have TSC, but the sealings for TSC might need coolant for lubrication, i don't know...

air throgh spindle would be very useful to remove chips from holes while helical milling.

In the latest issue of CNC Machining magazine from Haas they have an article about an outfit making oil field equipment and it mentions they use air through the spindle so it must be okay at least at low speeds.

The okuma I have is equipped with tsc and it also has through spindle air, so it must be useful to some shops. It also came with an air blast standard :p

I've not seen the Haas TSC seal arrangement, but for through air, you really don't need the seal to seal, because if some air escapes up above, its not going to mess with anything. I wonder if there is a way to 'engage the seal' only when coolant is being used?

...for through air, you really don't need the seal to seal, because if some air escapes up above, its not going to mess with anything....

This is true but if you have a contact seal made for liquid and you run it with air you can finish up melting things, as I discovered to my chagrin. :)

If they use a labyrinth seal there should be no problem.