[HELP] Coolant for the home hobbiest

[arvidj]

I am getting a lathe and have a mill that have coolant systems. In John's videos I often see him using coolant on his lathe and it looks like a good thing. While looking thru the Enco pages for a suitable coolant I was overwhelmed so an education is in order.

Anyone have any links or suggestions that would provide guidance or an education related to coolant, soluble cutting oils, cutting oils, etc. ... i.e. things I might put in the coolant system?

Something that does not take a lot of care and maintenance would be best as adding a skimmer or other items to control the growth of small organisms is not viable for a home system.

Thanks,
Arvid

[Dr Stan]

I worked as a machinist & tool maker for several years and consequently had multiple experiences with rancid water soluble coolant. Consequently I'm using a 50/50 mix of cutting oil and diesel fuel in both my lathe & mill. Its a compromise but works fairly well in ferrous and non-ferrous materials. Some will complain about the smell, but its one I like as it takes me back to my early days in the trade.

BTW, I've had contact dermatitis from water soluble coolant, but have never had it from oil based.

[PixMan]

I'm using Trico's Tri-Cool TC-1, a full synthetic coolant in my lathe. It's been in there for 6 YEARS and there's just two things I do to keep it fresh. One, I check the level and concentration (refractometer reading) about once a month because I do get evaporation of the water and concentration rises. The second thing I do about twice a year is use a hydrophilic pad to suck tramp way oil off the top of the mix. That keeps the oil from sealing off oxygen to the supply. When that happens, bacteria can fester and cause the rancid smell.

I had gotten two quarts of the TC-1 off eBay for short money years ago, but have since bought a 1 gallon jug from KBC Tools and that lasts a LONG time. Great stuff, I'll probably charge my bandsaw with a more concentrated mix when I ever get a Roundtuit.

BTW, there are a number of features you look at when choosing a coolant. Tramp oil rejection is a big part of successful use of full synthetic and especially, semi-synthetic coolants. Another is lubricity. A full synthetic is never quite and good in that respect as a semi-synthetic (which uses oils and emulsifiers to keep it homogenized with water.) In my applications, because I primarily use carbide insert turning tools and HSS drills I don't need lubricity as much as I need actual cooling, chip flow and low maintenance so full synthetic makes more sense.

A straight oil can be far more expensive overall and messy, not to mention more volatile at the cutting speeds I tend to run. My full synthetic can also be thinned to use in my mist coolant on the mill, though I've yet to bother charging the tank and try it. Thinning it out is something not so easy with semi-synthetic or straight oils.

[arvidj]

Dr Stan,

Thanks for the information. I would not mind the aroma but it is in the basement and I think Bev will object to "what have you done to stink up the house!!!".

Ken,

If it will be primarily HSS tools and drills and steel and aluminum would you recommend a full synthetic or semi-synthetic? I am assuming that my needs are more in the lubricity end rather than the cooling end of the spectrum, but that is an uneducated guess.

[PixMan]

Arvid,

I'd suggest the full synthetic, mixed at a higher concentration level for lubricity because of it's keeping qualities and the fact that you're in a basement shop. The Tri-Cool TC-1 I use has virtually no smell whatsoever, so it may be a good choice. It's mixing chart shows it can be mixed to (I think) as low as a 10:1 ratio.

I also have ValCool VP-910 full synthetic in my surface grinder, but had to give up my 5 gallon pail to bail out a friend. It's very similar to the TC-1 and cheaper in the 5 gallon pail. I should just bite the bullet and get a fresh pail of it. I get the same evaporation rates with that though it's got a more perfumey smell to it.

[arvidj]

Any thoughts on this ... http://www.use-enco.com/CGI/INSRIT?PARTP...A=404-3031 ... for $120 for 5 gallons?

Enco does not offer any ValCool products. ValCool VP910 is available thru Fastenall for $170.

The Tri-Cool is $190 for 5 gallons. Of course the $120 is a value only if it actually works and does not smell up the house.

[PixMan]

I used to work in a shop that ran the Trim Micro-Sol semi-synthetic products and they went rancid FAST. They've probably improved their stuff since then (15-20 years ago), but it left me with such a "bad taste in my mouth" that I'd never go back.

I would hesitate to get 5 gallons of anything unless you have big coolant tanks and plan to refresh them with clean coolant several times a year. I say this because coolants, especially semi-synthetic ones, have a finite shelf life and could start to separate their components in just over a year. Full synthetics have twice the shelf life, if not more.

My 2 cents.

[wrustle]

Not to disagree with anything Ken has suggested, but from my experience I would suggest the following:


For a small shop I would strongly recommend the Fogbuster coolant sprayer.

It is VERY easy to maintain.  With the unit I was using on my Yam Cnc lathe in my garage, it was mixed up one quart at a time, and lasted quite awhile.

See the unit hanging at the right end of the lathe with the blue coolant in it?  That's all it is, with a magnetic base and nozzle I could point right at the work where needed and a toggle switch within reach on the outside of the lathe.



You have very little waste, and though not as effective as a fully contained flood coolant system, it can prove very effective for the hobbyist in a home environment.

Yes......the sound of a "misting unit" sounds as though it would fill your house with mist.  NO.....it will not, unless you have the nozzle wide open with the air pressure set VERY high, then Yes.....it most likely will.  

But with your air pressure set low enough and your water volume set low enough, you get what equates to a mostly heavy watery spray where you need it.  Not a fine mist.

http://www.fogbuster.com/

I actually still have mine tucked away somewhere.  Haven't used it in years.  

Best Regards,
Russ

[EdK]

Hey Russ, how much air pressure is required for that setup?

Ed

[wrustle]

(11-12-2014, 07:40 PM)EdK Wrote: Hey Russ, how much air pressure is required for that setup?

Ed

According to their website Ed, 10-20 PSI is all that's needed.