coolant tutorial

I just acquired a K. O. Lee S618 surface grinder that includes a coolant tank and pump. I've been trying to learn more about using coolant but I'm finding little. Is there a "coolant tutorial" (Coolant for Dummies) that you can point me to? I won't be using this machine a whole lot and I hear stories about messy and stinky coolant. Advice, please.

Thanks,
Ron

the basic principals are simple, coolant greatly improves grinding as work pieces don't "grow" and you get a better finish......the downside is you have to be really committed to it as if you just leave it sitting there it will grow bacteria. Commitment means defenses like against bacteria including an oil skimmer, bubble and UV light source....filter stuff coming in is also good. I'm building the Mk II central coolant "server" with all of the above, as well as tight fitting lid and plastic liner...but alas its yet an incomplete project.

You can get away without it on on a surface grinder, but its better with. The chuck acts as a heat sink to a degree....forget it on cylindrical grinder, you need flood for that.

there's lots more details on it out there if you google

If not using it much I would try using more open wheels to avoid using coolant. It all depends on what your doing whether you "need" it or not. My favorite wheels for general grinding were induced porosity G wheels, free cutting and much cooler. Great when grinding graphite electrodes.

Surface grinding using coolant

arjay8 said:

I just acquired a K. O. Lee S618 surface grinder that includes a coolant tank and pump. I've been trying to learn more about using coolant but I'm finding little. Is there a "coolant tutorial" (Coolant for Dummies) that you can point me to? I won't be using this machine a whole lot and I hear stories about messy and stinky coolant. Advice, please.

Thanks,
Ron

Click to expand...

For grinding with coolant the coolant needs to be thin or it will be messy and difficult to clean leaving a residue on the chuck. Only add enough coolant to prevent rust. I used Kemcool "Less is better" than what is recommended by the supplier. Before Wire EDM I spent years in front of manual surface grinders; contour grinding die sections and gages. I like the coolant for flat work, but I prefer grinding dry for the kind of work I did and selecting the right wheels for the material and requirement of the work being ground. When grinding dry an electric chuck is better for high quality results. The residual magnetism after turning off the chuck holds the part and releases the strong hold to allow the part to relax. Let it cool on the chuck and lightly make a pass over the work to make the work flat. Getting flat and true size over the entire surface is a matter of technic. If your use of the grinder is limited, I don't think adding coolant is worth the trouble of cleaning and properly maintaining the coolant system.
All the Best.
Roger 02/26/2017

The two things that differ between grinding with coolant and conventional machining with coolant is the concentration (as mentioned above), and it's a good habit to let the wheel "spin dry" for a few minutes after shutting off the coolant. This is to prevent the coolant from soaking in to the bottom of the wheel and potentially have it explode on the next startup. I learned this from old literature so mabey it's been dubunked by modern abrasive recipies, but I've yet to have one pop on me.

Otherwise its normal coolant procedure. Keep it fresh and the right mixture.

I have many grinders that I use coolant on. I use Houghton HOCUT 795‑H. Can't recommend it enough. Some machines have had it in them for 8 years. I mix it at 8 percent. I use tap water and just mix it in a bucket with a yardstick. I don't care if I mix it oil in last or first. I check the concentration and if it gets low I just poor in coolant in the tank, get out my yardstick and stir. Lots of people will disagree with me but it works for me. I think coolant company's really make it sound complicated. I use the same coolant in mills and grinders.
Let the flame begin

Man That's Sharp said:

I have many grinders that I use coolant on. I use Houghton HOCUT 795‑H. Can't recommend it enough. Some machines have had it in them for 8 years. I mix it at 8 percent. I use tap water and just mix it in a bucket with a yardstick. I don't care if I mix it oil in last or first. I check the concentration and if it gets low I just poor in coolant in the tank, get out my yardstick and stir. Lots of people will disagree with me but it works for me. I think coolant company's really make it sound complicated. I use the same coolant in mills and grinders.
Let the flame begin

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I'm by no means an expert on either grinding or coolant technology but that mix seems a bit " Oil Rich ".

Most places I worked had a coolant metering system for all the processes, turning, grinding, milling etc so it was really sort of " one size fits all ".

As a consequence of that the dispenser was set to a 5% concentration. I used to keep a check on it with the " refractometer ".

Regards Tyrone.