DocsMachine
Titanium
- Joined
- Jan 8, 2005
- Location
- Southcentral, AK
Simple question with, I'm sure, a not-so-simple answer: What sort of issues might I face using cutting oil, rather than water-based coolant, in a small VMC with a 10K RPM spindle?
Parts are small, aluminum, relatively low complexity, and only moderate accuracy.
Part of the reason for using the oil is the machine will only be used a limited number of hours per month. I'm not a high-volume shop (yet) and I figure the thing will only see 10-20 total hours of use a month.
Oil eliminates evaporation issues, smell/rancidity, rust, and the need to frequently adjust concentrations.
On the other hand, I know it's nowhere near as good as a coolant, and heat issues may be a problem.
Is there anything else of significance I should know about? Reduced tool life? Reduced surface finish?
And, now, for the real heresy.
I've been using Mobilmet 426 cutting oil in my other machines (including a CNC lathe) and it appears to be working fine. But, being in Alaska, a single bucket costs me $260 including shipping.
I can get hydraulic oil locally for less than $70 a bucket. I know that's probably false economy, but just for the sake of the argument, what would be different about it as a cutting oil? I read about guys being able to tell when their soluble coolants get off-spec for concentration, and can tell the difference between brands.
One would presume the cheap hydraulic oil wouldn't have the proper additives to make a good cutting oil, but I guess the question is, how bad would it be? Chip welding? Insert breakage? Endmills lasting less than ten minutes?
Doc.
Parts are small, aluminum, relatively low complexity, and only moderate accuracy.
Part of the reason for using the oil is the machine will only be used a limited number of hours per month. I'm not a high-volume shop (yet) and I figure the thing will only see 10-20 total hours of use a month.
Oil eliminates evaporation issues, smell/rancidity, rust, and the need to frequently adjust concentrations.
On the other hand, I know it's nowhere near as good as a coolant, and heat issues may be a problem.
Is there anything else of significance I should know about? Reduced tool life? Reduced surface finish?
And, now, for the real heresy.
I've been using Mobilmet 426 cutting oil in my other machines (including a CNC lathe) and it appears to be working fine. But, being in Alaska, a single bucket costs me $260 including shipping.
I can get hydraulic oil locally for less than $70 a bucket. I know that's probably false economy, but just for the sake of the argument, what would be different about it as a cutting oil? I read about guys being able to tell when their soluble coolants get off-spec for concentration, and can tell the difference between brands.
One would presume the cheap hydraulic oil wouldn't have the proper additives to make a good cutting oil, but I guess the question is, how bad would it be? Chip welding? Insert breakage? Endmills lasting less than ten minutes?
Doc.