New to Mist Cooling

[gheumann]

I've been using compressed air only for a job I do repeatedly. I'd like to try mist cooling. I bought some KoolMist and the "OriGlam Mist Coolant Lubrication Spray System" from Amazon - all hooked up and working. If it matters - I cut .075 thick 6061 with an 1/8" bit turning 5000 RPM (my mill's max) - the shape of the work (and my skill level with MACH3) are such that I can't do it in multiple depth passes so I cut all the way through in 1 pass. I cut at F2 (inches).

Any advice? How much mist is needed? How do you clean up the mess afterward? I know this is water-soluble oil but if any is left around am I going to end up with any rust on my machine?

Thanks

 

[Bob Korves]

For high speed work on aluminum I would either use it dry, or use a small amount of coolant mixed with a lot of air to blow the chips out. Use the Kool Mist at the recommended concentration, not weaker or stronger. It should not be too messy if you are using it correctly. On aluminum, it will help to stop metal build up on the cutting edges. Get the mist nozzle right in close to the work where it can do some good, and you should not have too much trouble cleaning it up. WAY better than flood coolant in a home hobby shop...

 

[gheumann]

For high speed work on aluminum I would either use it dry, or use a small amount of coolant mixed with a lot of air to blow the chips out. Use the Kool Mist at the recommended concentration, not weaker or stronger. It should not be too messy if you are using it correctly. On aluminum, it will help to stop metal build up on the cutting edges. Get the mist nozzle right in close to the work where it can do some good, and you should not have too much trouble cleaning it up. WAY better than flood coolant in a home hobby shop...

Thank you! I will try it soon. I know it is hard to quantify but would you say the "right" amount of coolant is where you can see the mist but barely?

 

[Bob Korves]

Thank you! I will try it soon. I know it is hard to quantify but would you say the "right" amount of coolant is where you can see the mist but barely?

Yes, it is difficult to quantify. It might be difficult to see coming out of the nozzle, but you should see that the surface is getting wet, with very little runoff. If you see metal welding to the tool cutting edges, then you may need more coolant, more air, and/or better placement. Make sure that you are not making a fine mist, that is bad for your health, and it migrates away from the cutting area where you need it. Very little coolant is needed for most jobs on a mill.

On my surface grinder, I use quite a bit more coolant, to help cool the work even more, and also to help keep dust down from the grinding.

Feel free to practice and try different ideas for different jobs. It is difficult to do anything too far wrong...

 

[ttabbal]

I try to get enough to see the drops on the work, but small enough amounts that it doesn't puddle up. I like the heat from working the metal to almost evaporate all of it. Wipe everything down with some way oil after use and I haven't seen any rust. It's very scientific, as you can see.