Bad smelling coolant fluid

One or two month ago I finish my new coolant system on my old Stanko lathe - tried it, OK is works fine and I think I get more shining finish on my items
than without coolant !
Yesterday when I use the lathe again for a while there was a very bad rotten smell - why ?
I use ROCOL (1 part) and water (20 parts) for the coolant fluid.
How long can such a fluid be used in a normal heated workshop (now in summer time there is no heat at all) ? Can I add more water (and ROCOL) when the fluid is used little by little ? Is there a better (and cheaper) way - with some other stuff then the expensive ROCOL ?
Best regards KS, Denmark
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
KS wrote:

Infected. But when you write you finished it, then your coolant system was new and clean, right?

There are several Rocol types.

Believe it or not. I had one sitting in an open can (5l) for several (about 5) years without stinking, but seldomly used. Now, with more usage, it lasts a year or more until it's time to clean it completely. Coolant needs fresh air. Don't keep it in a closed compartment. Skim the oil off. You could even use a bubbler to get fresh air into.
The one I'm using now is from EUROLube (can look up what type), the one before was CIMCool (no further information available). But my mixture is 1:10.
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
KS wrote:

Bacteria at work!
That is one of the major downfalls of soluble oil coolants.
Some of the things that help a great deal, are to skim the oil off the top of the coolant tank, and to ensure that it is used frequently or aerated, such as with a fish tank bubbler. Both these are to reduce the anerobic bacteria's preffered environment, by keeping a level of oxygen in the solution.
There are chemicals available for adding into the solution as well, usually available from tool suppliers.
I use my soluble coolant at a slightly higher concentration, as I find that I have fewer issues with rust forming, in the event that some kind soul tops up the tank with a bit of water, thinning the mix too far to provide the rust protection that it is supposed to be able to provide.
Keep the oil off the surface of the tank
Use the coolant often, or aerate it with a bubbler.
There are cutting oils/coolants that are used straight, with no dilution. These may be worth looking for, if you do not wish to deal with the soluble oil coolants, which really do need to be in steady use. Unfortunately, many of the cutting oils also offer an objectionable smell and smoke as a trade-off.
Cheers Trevor Jones
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I drop the odd H&S inspector in there. Serves two purposes [1], No self respecting bacteria will grow on a H&S inspector
and [2 ] all the frothing and thrashing about they do trying to get out aerates the coolant
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 26 Aug 2007 16:16:21 GMT, John Stevenson

But what do you do about the smell? :-)
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 26 Aug 2007 17:28:14 +0100, Mark Rand

He just has to put up with it ....................
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 26 Aug 2007 17:28:14 +0100, Mark Rand

Presumably the bacteria help mask it......

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

No one will notice in that neck of the woods. The town's slaughterhouse was just opposite... :-)
I dump my H&S guys in Forbes Hole.
Regards,
David P.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Doesn't Peter object?
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

the bacteria will just have to get used to it...
--
BigEgg
Hack to size. Hammer to fit. Weld to join. Grind to shape. Paint to cover.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Shit !

That's why the smell disappears after a while when I start to use it again I think !

My kind of ROCOL can "take water up to 30 times" 1:30 - so the "manual" says!

I think the coolant keeps the lathe very clean and leaves a thin layer of oil to prevent rust - even in my 1:20 "resolution" BUT ...
I have experienced that when I'm cutting thread I need to "oil" a little more - maybe that will NOT be necessary if I use a solution of - say 1:10 - what did you experience ?

I will try to do that !

I can just start the pump to aerate it !

... and I think much more expencive - right ?

KS, Denmark
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
KS wrote:

Not so bad. There are things that can be done to adapt.

Very likely.

I'll take your word for that. I am unfamiliar with the particular product you are using.

The coolants I use at work are mixed at 6 percent oil to water. Our shop environment is very dry, so evaporation is a problem. Our coolant mixer gives us a 3 percent oil mix for doing top-ups. Our solutions tend to migrate towards the higher concentrations, with some measuring into 20 percent, by the time they are in dire need of refreshing or replacement. With the high concentrations, there have been no issues with rust. Our coolant performs well for us, though it may cause issues in a production environment. Our shop does very little production, mostly maintenance and repair work, so coolant cost is not a factor in the process.

Yes.
One thing I do with one of our mills, is to run the coolant for a while to get it well churned up, then dispense as much of it as will pump out, into a bucket. I allow this to sit for a few hours, to allow the oil to float up, and drain off the coolant from the bottom. Not as elegant as a oil skimmer, and nowhere near as efficient as a coolant filter, but cheap and easy enough to do.

Sometimes.
All coolants have their good and bad points. You have to get to know what is available to you, and what each has in cost and benefit.

Cheers Trevor Jones
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for your advices and time !
KS, Denmark

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The brand I use has an anti bacterial chemical in it. Just as well, as I buy it in 20 litre buckets! That's the secret, get the stuff with an anti bacterial agent, and buy a big container of it, like 5 gallons/20-22 litres. Mine cost much less that way, than a gallon at an industrial supply firm. Contact some of your local oil company agents. Sometimes you can buy it directly from them, and save a bundle of cash! I only buy coolants and metal from a retail source, when the wholesalers and manufacturers will not sell directly (rare).
Steve R.
--
Reply address munged to bugger up spammers



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.