Hello 

i am upgrading my 25" quench tank to a much bigger 50" tank. I have been using veggie oil with some atf to try to keep the flames down.  I have had good results with this combo. I have broken a few blades and found a nice small crystalline structure.  But going to the new tank I was thinking about upgrading to a actual proper quench oil. But before I buy 15 gallons of the stuff (not cheep). I was wondering what most folks are using here.  I have looked at the stickies under sword, knife and heat treatment they usually just say oil.  Now being I work in a refinery I have a little knowledge about oil (very little). The research I have done so far shows a wide spread in viscosity for quenchent oil.  I will list below. All will be normalized at 40 deg c /104 deg f.  And shown in kinamatic viscosity for reference

10% brine - .85

isodur 160 - 10

isomax 166 - 12.5

chevron 70 - 16.5

isodur 220 - 19

isorapid 227 - 24

hydrolic oil - 30

vegetable oil- 34

trans (atf) - 35.5

isorapid 459 - 49

sae 30 - 88 

so I found a great spread on quench fluid viscosity and added some of the other things people seem to quench with.  I know quench oil is made from a base oil with a anti- oxidation addictive. I am tempted to stay with the veggie oil as I know it well. The real question is how many folks around here are using quenching oil verses something else.  Hopefully I have done enough research on my own so I don't get yelled at for asking questions

Regards

otto

McMaster 11 second quench oil here.

Thanks

that seems to be 22  cenastokes @40 deg. C.  I will see if I can covert to kinamatic for reference 

And sorry I put it in the sword section because that is what I am working on. Figured go to the source for info. 

Centistokes and kinamatic is basically same. 

Parks 50 as I have some 19th century steel that was not hardening as much as I would like in warm veggie oil and shattered in brine....

There are differences in speed amongst the different kinds of veggie oils, too.  I'm not sure how exactly they play out, but canola seems to be the fastest of the veggie oils, faster than the 11 second oil but slower than Parks 50.  It's what I use on 5160, 1084, and my current go-to alloy, 80CrV2.  Gets plenty hard without stressing the steel.  Never seen a blade crack in the quench from pre-warmed canola.

The only disadvantage I see is it degrades over time and with usage, but for even sword length blade quenches, the price is low enough that occasionally swapping it out for fresh oil isn't bad.

Thanks stormcrow I do like the canola oil for the lack of hydrocarbons 

Yes the 6 oxygens that keep it from being a hydrocarbon are impressive compared to the 108 hydrogens and 71 carbons if I counted correctly

Excuse me,   where did you get the idea that there are no Hydrocarbons in Canola Oil? its all hydrocarbon

 All vegetable oils are organic hydrocarbons...

D

Yes. Any plant-sourced oil such as olive, corn, soybean and flax can be used industrially to make lubricants, oils, fuel, soaps, paints, plastics, cosmetics or inks. In fact, any organic hydrocarbon (including ALL vegetable oils) can be processed and denatured to make industrial chemicals. Proteins in milk can be used to make glue. Wheat and canola can be used to make ethanol, and canola seed can be used to produce biodiesel.

And hemlock is all-natural. Just ask Socrates.

Of course I may have a divergent view on things as recombinant DNA (GMO) is currently keeping me alive (Humalog insulin)  and if you think about it---where does petroleum come from?   Now both vegetable oils and petroleum based oils can be modified; often making them more dangerous to humans; but lets try to remember that everything is chemicals!  I would rate unmodified vegetable oils as being much less toxic than used motor oil.  However I haven't researched the engineered quench oils in depth yet.

The fact that industry is making non petroleum based quenching fluids for improved worker safety makes me think that oil based quenching fluids can effect you in a bad way. One msds I checked states " may cause respiratory or other pulmonary effects following repeated inhalation". Now that being said I work in a refinery and huff a lot of oil fumes and mist on a daily basis.  I don't like adding to it at home.  But judging from some of the responses I sound like a know nothing crackpot. 

Spent years of my life analyzing the whole suite of petroleum based products that are commonly in gas or liquid form.   Long story short, every variety is potentially hazardous. Some are worse than others.  Breathing any liquid oil vapor is potentially dangerous.   Most of the plant based oils are less dangerous than mineral oils because of their more complicated structure. On the other hand the stuff that come to live in them can, in some varieties, be actively poisonous on skin contact. 

Take away.  Treat is all with caution and avoid as much  skin contact and respiration as possible. Keep tightly covered when not in use.  Plant base materials should be disposed of when ever they become cloudy or smelly.

4 hours ago, otto said:

The fact that industry is making non petroleum based quenching fluids for improved worker safety    .... judging from some of the responses I sound like a know nothing crackpot. 

At first you said no Hydrocarbons, which is not the same as non pertol that you just referred too

A quick question. Has anybody tried silicon transformer oil? This would be a non petroleum quenchant.

And a quick comment - many a chemistry text book define hydrocarbon as a molecule consisting of just hydrogen and carbon.

Silicon?, or do you mean silicone?

Pesky e. Runs off if I don't keep a leash on it. Yep - silicone based. It does have a slew of methyl groups attached to it, but I think it is considered non petroleum based, synthetic....

Silicone modified  oils would probably not be really suitable for  quench.   Transformer oils are selected for their stability and their ability to conduct heat and not absorb moisture.  Their ability to transfer heat in contact would be limited by their general in ability to wet out hot surfaces.  ( These statements are based only on personal experience with silicone modified oils not technical investigation)

 

6 hours ago, Steve Sells said:

At first you said no Hydrocarbons, which is not the same as non pertol that you just referred too

Yes I misspoke I meant petroleum based hydrocarbons 

Charlotte You are the first person that I have known to have tried these types of oils. Don't all oils, brine, and water have some difficulty wetting the surface of the metal due to a vapor jacket at 1500 - 600 F temperatures? This is the first time I have thought about part of quenching.

Leidenfrost effect.

I've read enough of Kevin Cashen's comments on quench oils to know that there is a *lot* of engineering that goes into them.  It's all way over my head.

 

But I know canola does well for the steels I use, is cheap, and is less toxic.  So it's what I choose.  That's pretty much the extent of it for me. 

1 hour ago, Bo T said:

Charlotte You are the first person that I have known to have tried these types of oils. Don't all oils, brine, and water have some difficulty wetting the surface of the metal due to a vapor jacket at 1500 - 600 F temperatures? This is the first time I have thought about part of quenching.

Speaking only from personal experience,  The break down temp of silicone oils seems higher but they don't wet seem as effective as similar viscosity veg oils. My experience was limited to specific types of vacuum pump oils designed for pumping oxygen  and oxygen compressors,  I was told by a manufacture rep that they were similar to some of the oils used in transformers.  BTW  don't mess with used transformer oils.   Some transformers still contain materials that produce really nasty cancer causing effects. PCB's  for one.

Do a check on Gloc quench, I've used it for the last 5+ years and love it! Warmed to 125 degrees it works flawlessly, extremely consistent. I use primarily 52100 but also the more common simple high carbon steels. After 29 years of this I'm only just now making my first Japanese sword using Aldo's 1074/low magnesium so I'm anxious to see how it treats this steel. As a side note, I probably only harden about 50 blades a year (never figured out how to do this any faster),and I've only needed to do and oil change once in that time.  

Why would anyone put any magnesium in steel? it does not mix well. Viking you may wish to double check.... Mn and Mg are two very different  elements.