Coolant for surface grinding

[skipd1]

I have a small 6x12 Harig that I use to grind and finish my projects. I grind dry with active dust collection but sometimes I would like to use either brush on or spray coolant for some projects, like surfacing some toolroom grinding stones. What type of coolant would work best for this use and what would be the best method for its application?

Thanks

skipd1

[dalee100]

Hi,

When it comes to grinding, flood or nothing. You need to apply enough to wash the surfaces to keep swarf from sticking to the surface of the work and face of the wheel and getting recut. It will cause excess heating and bad surface finish and loss of accuracy.

Edit to add: I always chose a synthetic water based coolant. But I've used soluble oils at times and even straight oil. I wouldn't bother with grinding a bench type stone. Just get a cheap alox stone and rub them together, But if you must, I would work it dry and then wash later with soapy warm water and a stiff natural bristle brush to clean the pores.

[Mcgyver]

When it comes to grinding, flood or nothing. .

+1, and flood if its at all possible

[MrFluffy]

Hi,

When it comes to grinding, flood or nothing. You need to apply enough to wash the surfaces to keep swarf from sticking to the surface of the work and face of the wheel and getting recut. It will cause excess heating and bad surface finish and loss of accuracy.

Edit to add: I always chose a synthetic water based coolant. But I've used soluble oils at times and even straight oil. I wouldn't bother with grinding a bench type stone. Just get a cheap alox stone and rub them together, But if you must, I would work it dry and then wash later with soapy warm water and a stiff natural bristle brush to clean the pores.

While I agree with the main bulk, possibly the op is trying to grind in some precision ground tool-room stones, I've been thinking of doing the same. Rob Renz posted a video about it if that's your sort of thing :-
https://www.youtube.com/watch?v=DVLXsq7pi9Y

[engineerd3d]

One thing that I do not like about industrial coolants. Most people say that they develop allergies or problems after some time even though the coolant is supposedly safe. IMHO I think plain water would be best as far as health. With that said, when I ground my stone, coolant was not an issue, I did what Stefan did, I soaked the stones in water overnight. The dust was controllable and very easily cleaned up.

[skipd1]

While I agree with the main bulk, possibly the op is trying to grind in some precision ground tool-room stones, I've been thinking of doing the same. Rob Renz posted a video about it if that's your sort of thing :-
https://www.youtube.com/watch?v=DVLXsq7pi9Y

Exactly, that is my goal. Flood coolant is not a realistic option in my small shop. I do have excellent high volume dust collection on the grinder tho.

[dalee100]

Hi,

It's about keeping the surface of the work and face of the wheel clean. Spritzing the surface will not do that, nor will soaking. A wet surface is a sticky surface, holding the swarf in place. The swarf needs to be removed as best as you can and as fast as you can. Hence either flood it or work completely dry. If you wish for a "dull" stone, then the last thing you want is for any swarf to remain on the surface. Because that will tear up the surface and defeat your purpose.

Modern good synthetic coolants are hypo-allergenic when mixed at the correct concentration. If you get a case of the itches these days, it's because of poor sump maintenance and personal hygiene. There are all kinds of nasty anaerobic bacteria that can grow in the sumps. I've seen sumps I wouldn't approach without a heavy caliber gun. And it's hard to kill once it gets a foothold.

[skipd1]

Thanks everyone for the great info

skipd1

[JoeLee]

I sometimes use a cold air gun when grinding. It keeps the work cool and blows the dust into the intake chute.
I don't use my grinder enough to have a flood coolant set up. But that is the best way to go.

JL................

[3 Phase Lightbulb]

I have a super 6x12 Harig surface grinder too and was thinking about adding coolant to it. I was thinking of using a Kool Mist sprayer but just use regular or distilled water. I'm thinking of using the same on my BP which already has a Kool Mist sprayer and use water instead of the actual Koolmist coolant. I haven't used it yet but assume cleanup would be minimal and shouldn't have any of the concerns that misting the Koolmist has with breathing it in/etc. Anyone use use a Kool Mist air system with completely non-toxic coolant like water?

[Seastar]

I have a super 6x12 Harig surface grinder too and was thinking about adding coolant to it. I was thinking of using a Kool Mist sprayer but just use regular or distilled water. I'm thinking of using the same on my BP which already has a Kool Mist sprayer and use water instead of the actual Koolmist coolant. I haven't used it yet but assume cleanup would be minimal and shouldn't have any of the concerns that misting the Koolmist has with breathing it in/etc. Anyone use use a Kool Mist air system with completely non-toxic coolant like water?

What about the rust you will generate inside all the nooks and crannies on your tools?
May as well use a garden hose. LOL!
Bill
,
Bill

[JoeLee]

I have a small mister like that too. The problem with using plain water is if it starts, I should say when it starts to creep behind the vise jaws, under the vise and where ever else your going to have rust forming, unless you want to take everything apart and clean it when your done. With the anti corrosive additive you don't have to worry as much.
I've gone as far as packing paper towels around the part I'm machining to try and absorb or contain the runoff. It's a pain either way. I have a set up for the cold air gun on the mill also.

JL.............

[3 Phase Lightbulb]

What about the rust you will generate inside all the nooks and crannies on your tools?
May as well use a garden hose. LOL!
Bill
,
Bill

That's what I'm wondering. It's not flood coolant, it's basically a fog/mist and it's going on the part/vice/table. If just wiping the vise and table down or blasting them with some air removes the water then it might be ideal. Maybe at the end of the day, spray some WD40 on the vice/table to displace what ever moisture remains. I certainty don't care about cosmetic rust so what would really be negatively affected by misting water? The ways/ball screws are coated with oil so I think it's just the vice/table which can easily be wiped down afterwards. No? As for misting water on the surface grinder, I think there is even less to worry about.