cutting fluid/collant

[icman]

hi guys the fluid I use looks cream in colour and it is mixed 25-1 with water.Trouble is after a few months the fluid seams to separate and it goes almost clear is it because its cheap!!!!!! will it help if I mix it say 10/1 . Any suggestions please.regards mike

[Stuart]

I bet you mixed it the wrong way round .

In the deep recesses of the brain I recolect that it mattered or it will not mix

Read the label . I think it's oil first then water but I may be wrong

*******I was wrong please disregard*******
see below for a more enlightened response 

Stuart

[Jo]

Yes it will separate if you are not pumping it round the coolant system on the machine all the time. If it is in a container give it a shake to mix it up again.


As for the mix: the water provides the cooling, the oil the lubrication of the cutting edge, 20:1 sounds about right for the stuff I have. I don't know how much of it you have got but it lasts a long time.

Jo

[Steam Haulage]

I did a major exercise on water miscible metalworking fluids on dozens of machines using 500 litres to 25,000 litres of fluid in their tanks. These were machining a multiplicity of metals. I can offer a few comments on some of my findings.

I know there are as many opinions about metalworking fluids as there are
(concentrate manufacturers + water suppliers + metalworking companies + machine types + foremen + operators + laboratories) = a very big number, even in the UK.

1. The major problem with water mix types is bacterial growth, most of the bacteria are in the air around us.
2. Concentration needs to be, as Jo said, around 5% fluid. i.e. 5 parts fluid to 95 parts water.
3. Concentrate needs to be added to water (alphabetical order as in 'acid to water').
4. Most fluids today form emulsions. The separation seen above is the result of inadequate shear at the mixing stage. Industrially mixing is by an injector powered by the flow of water drawing the concentrate into the mixing head, somewhat similar to the injector used on steam locos. This ensures that the fluid forms microscopically small droplets in the water which do not have sufficient mass to re-agglomerate.
5.Bacterial growth must be carefully monitored. Humans have one of the most sensitive detectors of this fitted, in most cases, to the front of the face.
6. Most water mix fluid concentrates have a system of control by bactericide built in. This is consumed by the bacteria growing in the mix and when exhausted any new bacteria encountered can have a jolly time.
7. Scum and detritus accumulates on the surface of the fluid and this can form a constant supply of bacteria

So in my view I think that water mix fluid are not the best for the amateur machinist, the straight oil types are far more suitable as no water is involved.

I already know that many of you reading this will vehemently disagree: my response can only be each to her/his own.

Offered just as a contribution to what can become a very heated debate in some circles.
Jerry

[Jo]

Thanks Jerry 

I have just started experimenting with a straight cutting oil "Silk cut 100". So far I am pleased with it. I am using the traditional dab it on with a paint brush approach.

If I needed flood cooling I would probably look to fill  the suds tank and go back to the smelly (bacteria) water based stuff.

Jo

[Stuart]

To the OP

here is some info on how to mix the coolant
http://www.cimcool.ca/uploads/downloads/TechRpt_ProperMixPrac_EN_Nov05.pdf


Stuart

[Steam Haulage]

I wouldn't argue with anything in that leaflet except the review of type, these have moved on a lot since those days. There has been a tendency to develop fluids that do not contain ant bactericides as these tend to be skin sensitisers. Ask any operator! The risk is that once sensitised you will always be susceptible. Gloves around rotating machinery are a hazard in themselves.

Current work is aimed at fluids which act selectively to defeat 'bad' bacteria and feed the good ones. Tricky but it has been achieved. But usage is subject to the usual caveats, many companies are reluctant to change and many have not heard of them. Price is of course an issue. If you talk to the UK HSE inspectors in the Nottingham - Derby - Birmingham triangle or read the HSE's review of metalworking fluids available on their website you will get a better picture.

As Jo has mentioned oils I would just say that for myself I decided I did not need the almost constant maintenance that water mix fluids need, either changing frequently, at least one per month, or doing dip-slide bacteria counts to avoid the hazards. So on my machines I have the tanks filled with Castrol Ilocut 486. I think JS put me on to this and it has performed well, no water involved, surfaces always coated etc. etc..

Jerry

[sco]

Jo,

Have you a link to this silk cut 100 as a search just turns up ciggies or is it a windup?

Simon.

[Jo]

Simon: I had the same problem when I looked it up  My supplier provided me with a 2.5 ltrs hand filled container of the stuff out of his rather larger full sized oil drum full 

Jo

[Jim Nic]

Simon/Jo
Silkolene oil products are now made and distributed by Fuchs on an industrial scale, including a cutting fluid called Ecocut  (www.fuchs.com/fuchs_industrial_cutting_grinding_fluids.php)  This may be the up to date and/or correct name for Silkcut.
Jim

[sco]

Thanks Jim but I think we are going to need an expert to guide us through that minefield! Plus it's likely you would have to buy many gallons - I guess we could organise a group buy maybe if there was enough interest to divide into sensible smaller quantities.

Simon

[Jim Nic]

Or make friends with Jo's supplier 

[rodw]

Personally, and I am a self taught machinist, I think there is a lot of dated info on the net about cutting fluid  which predates the modern fluids. When I bought the coolant system for my lathe, the guys I bought it from (Hare & Forbes) sold me 5 litres of  HOCUT 797 BU. I don't use coolant a lot but its been in the tank for over 24 months and I topped it up once. No smell, no problems. If its just evaporation, I just add a bit more water. The 5  litre drum will last nearly forever.

[Steam Haulage]

Hi rodw,

I'm pleased you are pleased with the Houghton's product, although a US company they also have a lab. etc in Trafford Park, UK. One of the best.

Anyone interested you can find their Info. on Houghton's website.

Jerry

[///]

Anyone used Rocol Ultracut Premium?
We use it at work for our bandsaw and I've never noticed a smell, though I don't know how often it gets replaced, I've only ever seen it get topped up.

I've been given the go-ahead to take some to use at home but my machines are in the spare room of the house, so if there are bad smells I'll be shot.
I need to sort out a drip tray for the lathe before I can be the guinea-pig, so if anyone else has tried it I'd be happy to hear of their impressions.