Thread: What are you guys paying for cutting fluid/coolant?

Originally Posted by Graziano

Thanks for the recipe Log, I wonder what the Borax does. The first bunch of bananas is in from the bush behind the backyard and ripening in the laundry as we speak.

Hi Mark,
The Borax should help with shelf life (it is used as a preserver instead or with salt in some countries) and more importantly to inhibit mold. Borax is one of those magical do all chemicals. I use it as forge welding flux, you can use it a soldering flux, and hey it even cleans your pots, pans and linen!

Just finished a batch of old school beef tallow soap which should be rich in sodium stearate emulsifier. It turns out modern soap gets distilled or something to remove the stearate for sale as another product. The earlier Lux soap test batch of cutting fluid has completely separated now. Assuming this soap works, it would be a salt free, emulsifying soap I can mix in with some free used hydraulic oil (close to straight mineral oil) to make a basic coolant.

Originally Posted by Graziano

Just finished a batch of old school beef tallow soap which should be rich in sodium stearate emulsifier.

Tallow soap made with NaOH will give a hard soap. If you want a soft soap, as in a recipe in a previous post, you should use KOH. That will give you Potassium Stearate as the active ingredient. That is also known as 'Gardeners Soap' because it is easier to dilute into a usable solution. I'm sure there is a whole area of research/application there for the right person. I have some real soft soap made up if anyone is interested in trying it.

Originally Posted by burraboy

Tallow soap made with NaOH will give a hard soap. If you want a soft soap, as in a recipe in a previous post, you should use KOH. That will give you Potassium Stearate as the active ingredient. That is also known as 'Gardeners Soap' because it is easier to dilute into a usable solution. I'm sure there is a whole area of research/application there for the right person. I have some real soft soap made up if anyone is interested in trying it.

Thanks Burraboy, that's exactly the information I'm looking for, this batch reminded me of the soap my Grandmother made in the 1970's, a single cake seemed to last for 200 years even in soft water as solubility was low. Is there an easy source of potassium hydroxide?.

I got mine from a soap making supplier in the Penrith area, Heirloom Bodycare Shop, they have a website. Bought by the Kilo, which makes a lot of soft soap. I only used a third and have a lifetime supply of the soap. Let me know if you want to try some made up soap or want some KOH. Using the cold process it is trickier to make than hard soaps.

Here's an Ebay supplier of KOH, don't know how the price compares to a soap makers supply place though.

POTASSIUM HYDROXIDE KOH HHO HYDROGEN GENERATOR ELECTROLIYTE | eBay

Just in case you wanted to chuck some extra sodium stearate in I did a bit of Googling for suppliers of sodium stearate, didn't find any in Aus but is available in USA so maybe is available in Aus.

Cheers.

The Ebay KOH seller is up you way Graziano, you might be close, he may sell larger quantity cheaper direct (bypassing Ebay)

Cheers.

Originally Posted by Log

Here's an Ebay supplier of KOH, don't know how the price compares to a soap makers supply place though.

400grams for $11.99 thru ebay vs $15 for 1kg or $25 for 2kg at the soap shop. The ebay option is happy to post, but the soap place is not. I suppose it falls into dangerous goods category but suddenly becomes non-dangerous in smaller quantities for ebay merchants. If anyone wants a small amount, let me know.

Originally Posted by burraboy

400grams for $11.99 thru ebay vs $15 for 1kg or $25 for 2kg at the soap shop. The ebay option is happy to post, but the soap place is not. I suppose it falls into dangerous goods category but suddenly becomes non-dangerous in smaller quantities for ebay merchants. If anyone wants a small amount, let me know.

I'll check a few of the local chemical places and see if they have it, it turns out that white hardwood ash from burning the wood is a rich source. The early soap makers used to add some ash to their soap mix. I think mixing the ash with water and letting the crud settle before pouring off the water will get you a solution of potassium hydroxide in the water.

I mixed some of the home made soap, oil and water together and it readily formed a milky liquid with a few suds on top, will leave it for now and see how long it takes to separate. It's a cool experiment, if it works well it would allow me to make cheap flood coolant but it remains to be seen how well it compares to a commercial product.

I just got 2 5l drums of ports cut for nics. Im not shore if its suitable yet it has a saw blade on the lable

opps its called mobilcut af and its not even cutting oil. its a anti foaming additive.
oh well