Homemade motor oil/cutting water

anti corrosion oil, simply put is oil that has sulfur in it, the sulfur reacts with the oxygen in the air and prevents your steel from reacting instead with the air
its done super simple by just heating up basic oil with sulfur, since regular oil does contain some acid groups you may wanna use mineral (paraffin) oil, i believe this can be bought as "baby oil"
once its done you will notice the oil having turned a slight bit yellow, and as a bonus you may get some neat sulfur crystals

i dont know any particular measures for how much or how little sulfur you add to it

now you have basic engine oil, i wouldnt advise anyone to dump this in their car since theres probably some specifications for the oil they manufacture that makes it run extra well- it may work for hydraulic oil- and our next step
making saw "water"

you mix up the oil with water and add soap and blend it up until it doesnt seperate anymore, shaking it up in a plastic bottle will do really.

edit: totally forgot photo of the nice flaky sulfur crystals that remained once the oil cooled back down
https://gyazo.com/cf3ac7a64d62dfa7c40b04e4b8974645.jpg
https://gyazo.com/cf3ac7a64d62dfa7c40b04e4b8974645

I'm not a chemist, so I'm confused!

Sulphur plus water will give H2SO4, which is sulphuric acid, and is good for rusting away iron!

Long time ago I lived in Rabaul, Papua New Guinea. Rabaul town is in the caldera of an old volcano, well about 1900 years old. In fact a lot of the entire Gazelle Peninsula appeared from the same event. Many of the subsequent volcanos that appeared around the original volcano are still active, with lots of sulphuric fumes being in the air.

Cars tended to rust away there. It was explained to me by the senior volcanologist that the soil and the air contained lots of sulphur, which, when wet, formed sulphuric acid. Hence my confusion.

Comments from any chemist knowledgeable members would no doubt clarify.

Quote:

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Originally Posted by A J in WA

I'm not a chemist, so I'm confused!

Sulphur plus water will give H2SO4, which is sulphuric acid, and is good for rusting away iron!

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I was too but I looked it up and found elemental Sulphur (S8 - its molecule with 8 sulphur atoms)) is basically insoluble in water ~5µg/kg (5 parts per billion) so it won't form much sulphuric acid. To make sulphuric acid the sulphur has to be converted (burned in air) to SO2 which easily dissolves in water to make sulphuric acid. SO2 is produced by volcanoes, internal combustion engines, and coal fired plant exhaust and when it combines with water in the air is what makes acid rain

Sulphur is added to oils as part of what are called extreme pressure additives. It reacts with metals (esp iron) to form thin pressure resistive coatings that aids sliding and reduces wear and galling in gears and cutting tools. Sometimes the Sulphur is added as a compound like MoS. In Guy Lautards home brew for way oil he recommends adding a small amount of MoS to the brew.

Trefolex cutting paste is loaded with sulphur, which is probably why it stinks.

And isn't it good stuff!

This is what the MSDS says for Trefolex paste

PETROLEUM HYDROCARBON(S) 30-60%
SULPHUR 10-30%
TALC 10-30%
VEGETABLE OIL 10-30%
TALLOW <10%

Interestingly the most dangerous thing in there (under normal use) is the Talc (exposure limit is 2.5 mg/m^3)
The Hydrocarbons and Veggie oils exposure limits are 5 and 10 mg/m^3 respectively.

However, if it gets hot and catches fire the sulphur turns to SO2 which is toxic - this is why it should not be used with cutting tools that get really hot.
Interestingly SO2 has an exposure limit of between (depending on whose exposure limits you read) of between 0.2 and 10 mg/m^3.
The 0.2 mg/m^3 is the same for H2SO4 vapour.

I believe soil with fools gold in it (iron sulfide) when exposed to air/rain will react to form iron oxide and sulphuric acid.

Country around here has lots of granite loaded with flakes of fools gold. After rain there is a heavy black mineral on top of the washed ground. And pieces of steel resting on the granite rust much more then if they were on other types of ground.