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theGallery
08-03-2011, 03:00 PM
I have have been doing this hobby machinist thing for over 50 years but I have never used coolant. Even an old man should try something new at least once. I have a new PM45 gear head mill that came with a coolant system. I have a concern about water based coolant. Rust is not a friend of mine. I know it is probably in the head. The question. Could I us WD-40 as a coolant? The tank is small, maybe 6 quarts. I know it will be messy, but I would like to try it. Suggestions.

chipmaker4130
08-03-2011, 03:23 PM
After I started using coolant, I almost never work without it on the mill. All my cutters, including carbide, last much longer and the chips don't burn me!

I use water-soluable oil (rustlik) and water. Water absorbs heat better than most other liquids. The oil prevents rusting except where the solution gets under the vise and water vapor rises to the underside of the vise and causes a little rust after a while.

It isn't much of a mess for me either. I plumbed the wells at the ends of my mill table and run rubber hoses to a container underneath. I use a Noga coolant sprayer and I set it to a coarse, low-velocity sputter. A gallon of coolant goes a long, long way, and it doesn't fill the air with mist. I ususally don't even re-use the coolant. The setup came with a mag base, and I can easily move it to the bandsaw or lathe.

Gordon

SGW
08-03-2011, 05:00 PM
If it's a mist system, consider whether you want to breathe WD-40 for an extended period. The 95% to 98% water coolants are bad enough for me to contemplate.

Note that there should be no visible mist. According to Bijur, the cooling is supposed to come from the refrigeration effect of the mist evaporating into the air as it leaves the nozzle. The cold moisture-laden air does the actual cooling. The cooling effect is quite pronounced. You can feel it when it happens if you stick your finger in the airstream and slowly turn on the mist. Turn up the mist until you just begin to see a few small droplets condensing on a thumbnail held in the airstream.

As Gordon said, rust isn't much of a problem unless the coolant gets trapped somewhere.

If your coolant system is the flood type the rust concern would probably be the same. It's just going to be inherently a lot more messy.

tdmidget
08-03-2011, 05:14 PM
A mist of WD40 would be like napalm. Just hold a lighter under the nozzle and spray and I think you'll give up on that one.

klemchuk
08-03-2011, 05:19 PM
I switched both lathe & mill from water based coolant which caused rust and stains on the mill table to 75/25 mix of Rigid light cutting oil and kerosene.
Works like a charm, no bacterial growth in the tank, no rust, no stains.
I will not go back to water based even though it's cheaper.

chipmaker4130
08-03-2011, 05:28 PM
Works like a charm, no bacterial growth in the tank, no rust, no stains.

Kerosene supports a number of bacteria. It has a strong smell which you'll track into the house, and while difficult to ignite, once you do you'll have quite a fire.

Black_Moons
08-03-2011, 05:32 PM
I dribble some rapidtap on everything I cut. Works wonders. More of a lube then coolant really. REALLY needed for some operations like cutoff on the lathe, Anything to do with aluminum where I want a good finish.. Not so much for steel, but I bet it does help tool life a lot.

Black_Moons
08-03-2011, 05:33 PM
Kerosene supports a number of bacteria. It has a strong smell which you'll track into the house, and while difficult to ignite, once you do you'll have quite a fire.

Well, I guess its good that iv been using up all my (Several year old) kerosene that my brother left scattered all over my place (No really, 3 diffrent bottles of the stuff, all nearly full) as cleaning fluid for old rusty/greasy crap.

The Artful Bodger
08-03-2011, 06:02 PM
I would steer well clear of using any combustable liquid.

Even stuff like heavy diesel oil makes an explosive mixture when mixed with air. Just think about it, the smaller the particles the more surface area to volume and the more exposure to oxygen in the air, wood dust, flour dust, aluminium dust, all explosive when suspended in air.

chipmaker4130
08-03-2011, 08:06 PM
Well, I guess its good that iv been using up all my (Several year old) kerosene that my brother left scattered all over my place (No really, 3 diffrent bottles of the stuff, all nearly full) as cleaning fluid for old rusty/greasy crap.

Oh yeah, I use a fair amount of kerosene, just haven't used it as coolant. In fact, I often mix ATF and kerosene to make light quenching oil. In that case, I expect flame and often get it. That's fine with me, I just close the lid on the quench tank and that's that.

macona
08-03-2011, 08:10 PM
I use Koolmist 87 or Tricool TC1 for my spray mist unit. Works great for just about everything. And it washes off with running water and does not stink to high heaven. Have not had any rust issues either.

theGallery
08-03-2011, 09:10 PM
Thanks for all the input. I had some concerns about using WD-40. Based on all the comments I'm not sure what to do. I refuse to use a water based coolant. Bottom line is there a non water based coolant that can be used with a flood coolant system? If so what is it and where can I get it or should I just forget trying coolant. It seem a waste to have a flood coolant system and not a least try it. Thanks Guys. Information is knowledge.

whitis
08-03-2011, 10:21 PM
Cutting fluid Management in Small machine Shop Operations
http://members.multimania.co.uk/gerardryder/mp10/enviro/cuttingfluidman.pdf

Thread on PM about health hazards of cutting fluids:
http://www.practicalmachinist.com/vb/cnc-machining/anyone-here-get-sick-coolant-ingestion-187817/

macona
08-03-2011, 10:38 PM
It seem a waste to have a flood coolant system and not a least try it. Thanks Guys. Information is knowledge.

Thats what I thought till I tried it. What a mistake. That is unless your machine is enclosed.

JoeFin
08-03-2011, 10:44 PM
I refuse to use a water based coolant. Bottom line is there a non water based coolant that can be used with a flood coolant system? If so what is it and where can I get it or should I just forget trying coolant.

Well since your running a manual mill and "High speed Milling" and or "Chip Control / Deep Slot Milling" are not much of a concern for you. There are those who feel exactly like you, and don't feel the risk of rusting out the base of their mill are worth the benefits of coolant - among those would be Forrest Addy so consider yourself in good company.

Enco sells a self contained "Coolant Pump-Sump" set up for about $100. A 5 gal of Rustlics is another $100 and at 15:1 will produce a lifetime supply of 75 gals of coolant.

Mist Cooling is a very good option for controlling heat and prolonging tool life on a manual mill and IMO will produce a better finish. Except for the hot sticky chip that gets stuck on every thing.

That and a little grease on the bottom side of your vise during set up

flylo
08-03-2011, 11:08 PM
There's a place on ebay that sell a simple system for $29. They're in Grand Rapids Mi. I plan on picking up 4 systems. Auction # 140359593896.

theGallery
08-04-2011, 05:24 PM
I already have the flood coolant system. It came as part of a package when I bought the mill. My professional back ground with degrees in science tells me where there is water and steel there eventually WILL BE rust. That is why I am I was looking for a product without water. I understand water coolant is a good heat conductor with a major negative, rust. I am begining to believe the best solution is never try the system and continue the mill dry as I have for the past 40 years. It has been an interesting topic and discussion and I appreciate all the input.

macona
08-04-2011, 06:16 PM
Hangsterfers makes a light oil called hard cut. I have been thinking about getting a bucket for my lathe.

http://www.hangsterfers.com/cutting_oils.asp

Mcgyver
08-04-2011, 08:05 PM
I use soluble oil flood on most machines, love it. if from some reason you don't want to go that route, you could use a cutting oil flood. The Rustlick has worked so far, I found the tricool went rancid very quickly.

The Artful Bodger
08-04-2011, 08:15 PM
I already have the flood coolant system. It came as part of a package when I bought the mill. My professional back ground with degrees in science tells me where there is water and steel there eventually WILL BE rust. That is why I am I was looking for a product without water. I understand water coolant is a good heat conductor with a major negative, rust. I am begining to believe the best solution is never try the system and continue the mill dry as I have for the past 40 years. It has been an interesting topic and discussion and I appreciate all the input.


We cant live without water and we cant remove it from our environment, I suggest use the most effective coolant that fits the budget and take whatever protective measures are required. For example if you are concerned about rust under the vise just take it off and spray the underside with one of the under-car protection waxes.

lenord
08-05-2011, 02:30 AM
I use kool mist, about twice the listed strength, in a flood cooling system. It's in a gallon jug from Enco, blue colored. It works like a charm, no rust, no excessive vapor to breathe in either. It is suppose to be "green" too.

Kero and WD-40 smell too bad, makes me sick in a shop that is closed to ventilation. ( nearly closed anyway )

There is a white colored water soluble oil that I use to use. It grew smelly bacteria in it. Might have been something else, but I think it was bacteria. That made me sick too.

flutedchamber
08-06-2011, 09:39 PM
I've used Mobilmet 760 by Mobil. Works well, extremely little smoke and an almost unnoticeable scent.