smokeless cutting oil

[Chris12Participant @chris12]

Hello,

 

I have been using Rockoil cutting and tapping fluids the past couple of months, and noticed it is smoking quite a lot, with an unpleasant smell. I dont have much ventilation in the garage, except opening the main door. As i use the machines in the evenings, it might annoy the neighbours pretty quickly.

 

I had a look at some potential replacement, namely Anchor Lube, Mollyslip MWF and Mollyslip MCC (this one seems to be the paste version of MWF). These seem to be mostly for drilling and tapping, though they are also indicated for cutting. And they are advertised as smokeless.

Does anyone has some experience with these products ? Or any other product to recommend ?

 

Thanks,

Chris

[David George 1Participant @davidgeorge1]

Try solubul oil coolant which you mix with water. It also helps to keep your job cooler. I use a squirt or two from a used washing up liquid bottle. The only problem is you need a tray to catch the run off  to prevent it going on to the floor. I made a three mm plate tray with a welded edge.

David

[Nigel Graham 2Participant @nigelgraham2]

Smoke or vapour?

Either, if copious, are from overheating.

Unpleasant smoke in the volumes you imply tell me it is overheating to the point of decomposition. It should not do that.

I suggest either over-ambitious machining or a good product incorrectly selected for the task.

Are the products really for general machining, or rather for fairly light duty such as low-speed, shallow-cut  screw-cutting, and hand work with saws, taps and dies?

Try a neat or soluble cutting-oil made for turning and milling – but remember the soluble ones especially are meant as coolant as well as lubricants, ideally by flowing over the work rather than brushing or spraying.

Also examine the cutting conditions to ensure you are not pushing things too hard.

[DiogenesParticipant @diogenes]

If you mean for milling and turning, I mostly use carbide dry for steel, CI, and Cu.alloys, and a bit of paraffin or WD40  for ali. just to stop it sticking to the tool edge.

The reason for this is that dribs and drabs of fluid can seem to hold chips and debris in the cut, and full flood coolant makes too much mess.

I use CT90 for drilling (because I have a bottle) and Temaxol for reaming or tapping.

[Charles LamontParticipant @charleslamont71117]

It sounds as though this product is unsuitable for turning, as is the Rocol RTD that I use only as it says on the bottle for reaming, tapping and drilling (and, in combination with a slow speed, for getting a good surface finish on gummy aluminium castings.)

I use HSS tools for the most part, and don’t like soluble oil. For cutting steel I use neat cutting oil instead. I use Morris’s Cora B, but I dilute it 50/50 with paraffin. This mixture is brilliant for getting a good finish with light cuts, but as I have no pump (yet), only a washing-up liquid bottle, I can’t flood a heavy roughing out job and admittedly it does get a bit smelly with paraffin vapour.

[JasonBModerator @jasonb]

If it is this one then that is not really for turning. Primerily for tapping/threading but can be used for drilling and reaming where it is unlikely to get hot.

[Chris12Participant @chris12]

I’d rather avoid coolant, considering the mess it is making. Might change my mind at some point.

[JasonB]

On JasonB Said:

If it is this one then that is not really for turning. Primerily for tapping/threading but can be used for drilling and reaming where it is unlikely to get hot.

Do you have another product to recommend?

[JasonBModerator @jasonb]

As others have said the soluable oils don’t smoke but if used in small amounts can boil off the water content which may condense on cold shiny bright metal, really they need to be used in larger quantities so the heat of cutting does not drive the temperature up.

I mostyly cut dry sometimes adding a little soluable oil just for final finishing cuts on steel where you are unlikely to be generating much heat. The 5lts of Gulf soluable oil that I bought probably 40yrs ago is still half full you can see it does not get use dmuch and when it doe sI mix it 10 to 1 rather than the suggested 20 to 1. I would imagine the soluable one ARC do from Rockoil would be similar to the Gulf.

[Neil LickfoldParticipant @neillickfold44316]

All cutting oils smoke, including the water based ones, the oil will still smoke, although in the water based ones, the smoke is disguised  with the water vapour.

Volume is the only way to reduce smoke, be it oil or water based soluble cutting oils.  Breathing any of them is never any good for your lungs long term.

Some form of ventilation that draws the smoky steamy air away from you and out the building somewhere is always a good thing.

[Chris12Participant @chris12]

Thanks all for your inputs. I think I will need to think about some sort of extraction or ventilation..

[bernard towersParticipant @bernardtowers37738]

Im getting to the last of a big batch of Texaco neatcut and that doesnt smoke very much so I will be interested to see whats recommended.

[Chris GunnParticipant @chrisgunn36534]

Chris, i would go for soluble cutting coolant. This is also much cheaper than cutting oil. You will need a good drip tray and a tank and pump, and flood the work. A good chuck guard should collect any spray from the chuck. You will get longer tool life as well.

I would not use cutting oil anywhere you have tooling or anything that runs fast enough to throw it around, impossible to clean it up, unlike soluble overspill. Cutting oil is used in industry in low speed situations or totally enclosed automatic machinery, where the oil can be properly contained and dealt with.

A soluble coolant system could be less expensive than ventilation.

Chris Gunn

[Chris12Participant @chris12]

I may have a look at this option then. Artisan Makes had a video about making a cooling system with an aquarium pump. Might give that a try.

[Howard LewisParticipant @howardlewis46836]

Fir general machining, if not cutting dry, I use soluble oil.

Rocol RTD is for tapping, i.e. very low cutting speeds. It is intended for tapping, not as a high cutting speed lubricant.

No wonder that it smokes, it is being overheated, and probably does not function as intended.

But even neat cutting oil will smoke slightly when used for milling.

Flood cooling with soluble oil not only lubricates the cut, but helps to flush away swarf, improving surface finish, and probably extending tool life.

If you use the right product, your problems may well reduce!

Howard

[Graham MeekParticipant @grahammeek88282]

For over a year now I have been using Smith & Allan Neatcut 32 cutting oil. It is a good all rounder which can be used on various metals. When used on brass with the correct insert tooling it produces a near mirror finish. I know the books say brass does not need any lubricant, but it is mentioned in the Smith & Allan write up so I thought I would try it. Using it also stops the swarf from brass flying everywhere.

It is good for tapping and reaming so there is only a need to have one product.

The usual disclaimer, just one very satisfied customer.

Regards

Gray,

 

[peter1972Participant @peter1972]

I recently tried using some neat CT-90 when turning 42mm diameter mild steel (with TiN coated carbide insert). I can’t say I noticed any improvement whatsoever. Does cutting oil really help when turning? Surely it can’t reach any of the cutting faces of a lathe tool near the cutting edge.

[Julie AnnParticipant @julieann]

As discussed above CT-90 acts a lubricant when tapping/reaming, often by hand. It is not intended for turning, which is why you didn’t see any difference. Cutting oils intended for machining are primarily used for lubrication where high cutting forces are involved; gear shaping for instance.

Soluble oils, which are intended primarily for cooling when machining, may make a difference to surface finish. But it is heavily dependent upon the material and speeds/feeds. Soluble oils really need to be used as a flood. The odd dab or squirt has little, if any, effect and may even be detrimental due to short term shock cooling.

For manual machining I use flood coolant mainly with HSS tooling. Carbide is run dry. On the CNC mill I use flood coolant irrespective, but that is mainly to wash away swarf rather than specifically for cooling.

Julie

[FulmenParticipant @fulmen]

As Julie says there is nothing wrong with running carbide dry. Unlike HSS it actually prefers to run a little hot, the coatings aren’t really effective when cold. Most of us amateurs run the inserts far, far below their maximum capacity.

I still run coolant with carbide when running heavy cuts, but more to keep the part cool and chip control. Hot parts can throw off measurements, and getting sprayed with red hot chips is just as fun as it sounds.

[Chris12Participant @chris12]

I just bought some soluble oil to give it a try, thinking to just use a brush to see the result. Based on the latest replies, it looks like it’s at best ineffective. Does anyone apply soluble oil with a brush ?

 

I have some carbide tools that work fairly well, though I would like to switch back to HSS.

[Neil LickfoldParticipant @neillickfold44316]

I have found that soluble oil when mixed at 10% to 12% gives the best tool life and surface finish and rust protection. When mixed at the lower end, I found things go rusty and their is a measurable reduction in tool life on a cnc lathe.

So at home for my bottle of cutting fluid, I mix it at 12% or 1/8 oil and fill the bottle with deionized bottled water. It has no chlorine or fluoride or minerals in it. It does not seem to go off either .

The other oil I now use is the Blaser CFS 35 . I use it for tapping and a very light coating on a surface with a brush. Yes it smokes.  The other I use is the covid hand cleaner.  It is an IPA gel with a small amount of castor oil in it. works well for finish cuts. Yes it too smokes as well or fumes.

I have set up a ceiling fan that draws air out of the shop towards the upper corner. It draws air in from the side doors, so when on the S7 for example, the smoke rises and goes towards the corner of the room behind the spindle.

I do my best to avoid the traditional carbide turning tools that have a small radius on the cutting edge, as they take too much cutting power to use. I use where possible the ground carbide inserts that have a sharp edge, be either coated or uncoated.  There are now a whole new range of sharp edge coated carbide insert grades that work really well on the home hobby lathe and will give a very good finish on mild steel.

The IPA or hand sanitiser on mild steel works really well to give a good surface finish as well.

Neil

[Chris12]

On Chris12 Said:

I just bought some soluble oil to give it a try, thinking to just use a brush to see the result. Based on the latest replies, it looks like it’s at best ineffective. Does anyone apply soluble oil with a brush ?

 

I have some carbide tools that work fairly well, though I would like to switch back to HSS.

Where did you buy it, I’m running a bit low on SCO.

[Chris12Participant @chris12]

I bought it directly from westway oils. They have 1L bottles, which should last me quite a bit once diluted.

[VicParticipant @vic]

Thanks.

[Julie AnnParticipant @julieann]

I use Castrol Hysol XF, a general purpose soluble oil for turning, milling and grinding. Concentration is 5/6%, checked regularly with a refractometer, as per the instructions. I never have a problem with rust on my machine tools. The soluble oil seems to be happy sitting in the coolant tanks for years without suffering from degredation or causing smells.

Julie

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