Great coolant except its toxic

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So I invested in a coolant sprayer for the lathe that hooks up to the shop air and draws coolant from a container with a flexible plastic hose. Vacuum in the spray head pulls the coolant up to the nozzle. You can adjust the amount of spray with the valve on the unit. I picked up a bottle of water based coolant that is supposed to be good for everything. It was all smiles and chuckles until I read the label on the coolant jug. It is toxic! You are instructed to avoid all contact with skin and eyes. If it touches you a flush with water and trip to the emergency room is recommended.

Sheesh. Who are these jokers? This stuff is being sprayed on a rapidly rotating workpiece. It will splash everywhere. I will be coated head to foot in it and breath it to boot. Are they kidding?

Is there a better option for a water based coolant? What do people use in these spray systems? Or should I order a HazMat suit and hang biohazard signs on the door of the shop?
 
What is the coolant you have bought ? You may be the victim of an over the top warning label . If any skin contact results in a need to go to hospital the coolant would be regarded as extremely hazardous and its sale would be restricted .
 
It’s a generic coolant of no particular brand. I suspect the lawyers have got involved in the warning label but the warning about skin and eye contact has given me pause about using it in a misting system.
 
Hi,

Concentrated coolants are very often hazardous to you. But when you dilute it, it's perfectly fine.

This is why on a commercial floor refractometers are used to check mix strength. But as a hobbyist, as long as you are close to the proper ratio, you should be good to go.

Some people do experience rashes and skin irritation no matter what.

So don't worry to much. As long as you don't eat or drink the stuff in large quantities, you should be fine
 
Was this packaged or sold in California? EVERYTHING in California will kill you, even food...
 
Further research has revealed specific types of coolant for misting, which is what I want to do. What is the difference? Hopefully a misting coolant is less toxic since you will be breathing it all day sitting at the lathe.
 
I don't know about that difference - I do remember that after many years as a production turner my Dad developed an allergy to coolant - but just had to kind of deal with it. Contact dermatitis seems to be like that - it can not come on at all, or come on all of a sudden, seemingly at random. I got work to buy me a great new pair of toecap rigger boots, lined and everything, because I thought I could also use them for winter motorcycling, but when I went out and got soaked through it seemed my feet had other ideas and I developed some kind of spontaneous allergy to something in the tanning of the leather - all red, pimply and itchy as hell. If you do suddenly go allergic, it's only a couple of weeks with cheap hydrocortisone cream from the chemist counter and you're back to normal - so I think it's a suck-it-and-see thing.
 
Just water is the safest coolant, but can rust things though. Some vege cooking oils also work well. Like Rice bran oil for example. The secret is to use very little of the coolant, and relies on the surface contact and evaporation to do the work and make it disappear in the surrounding air. So after like 20 seconds, it should just show an area on a paper towel just getting damp. Using some form of vacuum to draw the air sprayed on also helps, but a lot of setups can't have the vacuum channel around it. Keep away from Chlorinated coolants at least.
 
Kind of like my Harbor Freight roll a round tool cabinet. The instructions say that before moving the cabinet, it should be completely unloaded, moved and then the tools replaced!
 
Actually there is significant evidence that these misting systems are bad for you in general. You end up with air heavily polluted with the mist leading towards all sorts of health problems.
 
Just an observation......

A lot of the guys I watch on YouTube don't use misting systems all the time. Quite a few videos show turning or milling dry or with only a brushed-on cutting fluid once in a while. Some may also set up coolant only when needed.

I once was going to build a mister, but have not done so yet.

I tried using a compressed air stream to keep chips out of deep pockets I was milling and add a little cooling and that seemed to work well: It was not a definitive test as I also used premium end mills chosen for the task. (And yes, I had a major cleanup to do after that procedure.)

--ShopShoe
 
I understand that you want very little coolant in the air stream, just barely enough to get the work damp as opposed to clouds of mist. I just want this for steel. I use WD 40 on aluminum and cut brass dry. Can’t find a local source for misting coolant in less than 20 litre pails. KBC will sell a gallon but shipping is more than the purchase price. There must be a home brew recipe for a suitable coolant somewhere out on the web.
 
Ethanol can be used as a non ferrous misting coolant, plus it is soluble in water. Used neat, it won't cause rusting.
 
I don't know anything about misting systems but I'd be cautious about the amount of ethanol vapor you're creating at once. One spark with the right stoichiometric ratio and you've got a nice explosion on your hands (lots of moonshiners had this issue). Of course if it's only a tiny bit then you're not going to get much of a reaction.
 
A different solution I’ve read about is to use regular cutting oil in the mister. Place the reservoir fairly high so it almost siphons out. Use only enough air to get it to spit out drops rather than a mist. This mimics the brush/hand applied method.
 
Ethanol can be used as a non ferrous misting coolant, plus it is soluble in water. Used neat, it won't cause rusting.





phil
Are you sure about the Ethanol. Ethanol is a simple alcohol with the chemical formula C₂H₆O
It has a flash point of 170°, I don't think I want to spray a mist of Ethanol on metal that comes off and turns dark blue is seconds which means it could very be a good recipe for a fire?
 
Then again sitting in a spray of ethanol all day would make you forget all your problems. Don't think your parts would be to spec in the afternoon. The home brew recipes on the web vary from mixtures of vegetable oil and RV antifreeze to straight mineral oil with some water and dish soap. The antifreeze suggestions include ethylene glycol ( automotive antifreeze, very bad stuff ) and propylene glycol. PG comes in industrial, pharmaceutical, and food grades. The better grades are used in asthma puffers and e-cigarettes, so not too toxic unless you drink it. I dug into the info on a typical commercial product, in this case Kool Mist. It has two grades, 77 for heavy duty, and 78 for light duty. The 78 is specifically for misting and seems the best choice for a home shop so I checked the SDS sheet on the KBC web site. The "Hazard-determining Components" are listed as "Poly(ethylene glycol-ran-propylene glycol) monobutyl ether". The common wisdom is that Kool Mist is based on propylene glycol, which is good depending on grade. The SDS description seems to include ethylene glycol as well, which is disturbing. Anybody know what that label actually means?
 
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I generally use the cool-mist 77, BUT, be aware, it isn't recommended unless you have good cross ventilation and breathing the overspray isn't good for your lungs. Esp if you have breathing problems due to old age or general decrepitude, (LOL).
 

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