Need Help!- What coolant for me?

[jevs]

I need to decide on a coolant for my Pratt & Whitney CNC milling machine (see picture with sides off and starting to retro new electronics). It will be a flood coolant setup. This machine is 32 years old and has virtually no rust on the table or ways etc, and I want to keep it that way. I don't think it ever had coolant used on it and it was just used at a university to teach programming. Anyway, this thing looks better than most machines a year old, so I don't want to destroy it with coolant that will cause rust.

The problem is that it will be used very little and could sit for months at a time with no attention paid to it. I have used kool mist in my bandsaw and all the raw surfaces are now covered in rust. I can't let that happen to my mill.

I need the coolant to be compatible with all types of metal and all types of cutting and tapping etc. I have a 7 tool tool changer that I plan to use for who knows what, but I do have tapping heads that I plan to use. I never know what I will be doing, since this will get used for general purpose and hobby stuff here and there. I don't really know what I am going to make yet, but I do have thoughts of a scratch built CNC router....

I am really scared of using anything with water in it, since I see what happened to my bandsaw. I can't say the coolant caused it as it is humid here in the midwest, but my dry mill and my dry lathe have no rust on them. I do keep them coated with oil as well as I can though. I never did anything with the bandsaw but cut and leave it and fill the coolant when it stopped spitting any out. I always mixed it rich too, but it may have sat for 6 months without use or care.

I can't rely on myself to go out there and check the coolant constantly and add to it and adjust the mix etc. during the long periods of time I may not use it.

Is there any coolant that I can use that won't cause rust from lack of use or not constantly having to monitor the mix that will allow me to do all operations? I would think the water would evaporate leaving behind the non-rusting solution, but my bandsaw is rusty now.

Maybe I just need to spray it down with something after every use to prevent rust? With my bandsaw, I just use it and walk away, so it just relies on evaporation to dry off. There is no way I can dry my milling machine table off after every use to get rid of all coolant. It would just take too long. I could spray it with something though after each use.

Anyway, I need to order some coolant ASAP, as I am out in my bandsaw and want to use the same stuff that I will put in the mill. I need to use the bandsaw to cut some parts I am fabricating for the mill

Any advice would be appreciated as I am really worried about what to use. I am currently retrofitting the mill with AC servos, VFD, all new electrical components and wiring etc. so it will be nice and I will have some money in it. I want to keep it in excellent shape.

Thanks

[DareBee]

I had to play with coolants for a long time to get one that would handle sitting without turning into algae pudding.
I am happy with Nocosol EP Super.
No rusting issues like I have seen with other full synthetics.
3 - 4% mix on the refractometer.
It is recommended to spray down the bare metal with a light rust inhibitor before leaving sit.

[jevs]

Any recommendation for a rust inhibitor spray?

Also, will this protect the machine if it is sprayed right over a table and T slots that are still damp with coolant?

[DareBee]

Your guess (product research) is as good as mine.

I hit mine once a week with WD-40. WD stands for water displacer so it works through the water (after use). This is only a marginal method, I am sure you can find better.
If you are not diligent you may have to do some stoning (with WD).

If you are really fussy, you better towel it down.
Whatever suits your fancy

[Perfect Circle]

Trim Sol for the coolant & put a fish tank air pump in the coolant tank and run it when not in use or all the time..Also a good lube would be LPS #1 for short down times a couple of weeks...and LPS #2 for long downtime Months up to a year...Even longer would be you guessed it LPS #3 up to 5 years...this is what I use and have never had any problems. With the coolant the air pump keeps oxygen "Air" in the mixture to inhibit Anaerobic Bacteria growth that is what will grow and eat your coolant and the waste product from the bact. is what sours it..
Oh and keep the oil off the surface of the coolant as much as possible.

[underthetire]

I don't care what coolant you pick, all of it will rust or stain. I have tried in the past many different coolants, we used them in the showroom machines, only way was to remove all tooling and wipe everything down then use a light oil. WD40 on machine tools can be death. LPS is fine. If you really want to keep rust off, and paint on, the best i've seen is Hangstefers (sp) missle lube. It's a high flash point oil, and will keep everything nice. Downside-it's oil

[jevs]

Are there any good flood coolants that don't have water in them at all? Some sort of full synthetic or something.

If there are, can they be used without creating a horrible mess?

[doorknob]

Originally Posted by underthetire WD40 on machine tools can be death.

Can you elaborate on that part?

[jevs]

I have started contacting manufacturers and asking them their advice, but unfortunalty I don't have any free time during the day.

So far I sent Hangsterfers an e-mail and they are going to get back to me.

I talked to a couple guys at Master Chemical and they recommend Trim 685. Due to the sporadic infrequent use I will likely have, it still sounded like I could run into issues. Messing with coolants seems to be non friendly so far for the occasional user, unless you don't mind rust or have lots of time free time to spend babysitting coolant when your not even using the machine. It just seems like playing with fire. They also told me that I should not coat the machine with something else when I am not using it because it will just contaminate the coolant and cause issues. So, that is not very reassuring either

Some other coolants I saw with positive remarks on here are:
Rustlick WS5050
POWR-CUT HD
Houghton Hocut 795-B
Greencut
Apex 9100
Tricool
Qcut 251C
Valcool

Haven't had a chance to find any more out on these.

I have concluded that if I want to "play with fire" I probobly need a refractometer though.

I hope I find something that won't rust or promote rust on my machine......

[DareBee]

I have been through this process for many years with my machining center.
Have skimmers and aeration system.
Any of the "milk" coolant (Blasers, etc) turns to **** while not used.
I have no rust issues with the EP Super and the WD, some discoloration though.
LPS2 and 3 are great products but need wiped out before use again.

Thats it, do what you will.

[underthetire]

Originally Posted by doorknob Can you elaborate on that part?

Basically, the castings will age, the coolants and what not will start a rust process, but it will cure, and not really rust any further. WD40 takes this away, and will allow the castings to continually age, continually rust. It's also bad for way cover seals, it will dry them out. A mineral oil is still the best to put down for this reason.

[SmoggyTurnip]

Originally Posted by underthetire Basically, the castings will age,.

I don't understand what you mean by this. By "age" do you mean rust? If so are you saying that WD40 causes rust?

I don't know what you mean by "Cure" either. I never heard of rust curing.