Diamond Abrasive Lapping Fluid

[Tom Bussey]

Diamond lapping fluid is basically water soluble coolant. It is coolant that is mixed with water and it gives the water some added features. But some of the problems with it is it get stronger as the water evaporates and it needs to be tested often. Other problems that can arise are coolant allergies that develop over time. The the major problem is a residue is left behind and that will cling to a surface in the form of a with a film. and that will need to be cleaned off before the surface can be used again.

To get to the point is can be a sticky mess that needs to be cleaned with water and a brush, and it takes time to dissolve. And the finer the grit easier the easier it is for the coolant to load up around the diamonds.

People think they need it because one of the selling points is it stops the metal from rusting. And it will do that. but the mess left over from repeated use gets harder and harder to clean off.

Just plain water is a better lapping medium. The plate can be cleaned very easily with water after use and after wiping it down with a clean paper towel, I finish it off with a hot air gun or a hair drier. Water can't cause rusting where there it no water

The coolant cost $13 for a 3.4 once bottle and will be gone shortly. My Wagner hot air gun was about $30 and I have been using it for lots of different purposes for over the last 5 years. I use it to dry my diamond lapping plate and in that frame no hint of rust.

You can run out of the lapping fluid but water should always be available.

[Tom Bussey]

An after though is your wife's hair drier will also work very well. Just don't tell her if you want to keep on living. I guarantee you she will have no since of humor.

[Derek Cohen]

Thanks Tom

I have always used the same lubricant for my waterstones - water plus a little liquid soap. I am fortunate to have running water in the workshop, and so just rinse and stack the diamond stones to drip-dry after use. Never had an issue with rust - if there is anything like this, it is the swarf that was not cleaned away at the start.

Merry Christmas all.

Regards from Perth

Derek

[James Pallas]

Thanks Tom. I’ve thought of buying that stuff at times. I’ve been using diamonds since they came out in the 70s and have used windex and water. I dry them carefully and brush with a stiff fiber brush, no plastic. I’ve been successful so far. I won’t be wasting money on that fluid.
Jim

[John Stankus]

The sds for the trend stuff looks like naphtha and hydro treated petroleum distillates

If you are worried about rust some edta in water should work (probably evaporust as a lapping fluid would work)

Probably best and easiest is water with a little soap, and dry the tool when done

[Tom M King]

I keep a button start Propane torch on the sharpening sink. It waves water right off the tool.

[Tom Bussey]

A propane torch is a great idea.

[chris carter]

I just use windex. Can't cause rust and it evaporates off all on its own.

[Tom Bussey]

Chris,

I am not disagreeing with you at all. Nickel does not rust so any rusting that goes on is the grit removed form the object being sharpened. I wrote this because there are a lot of people who hater spending maybe $100 don't want anything to happen to it and therefore fooled into thinking they need to spend another $15 for the fluid. Great marketing though, I also posted this on a different forum and it seems that Windex as ammonia in it which brakes down the Nickel bond. So according to him Windex is a no no.

[James Pallas]

I have 2 DMT stones from the mid 1970s when they first came out I think. They both still work. They are not as aggressive as they were but are still very useful. I have always used windex. The nickel is still there, discolored some. I have an extra extra fine, a extra fine and course plates that are my “new ones” at least 10 years old. Same thing windex and they look and work ok. I never leave them wet and rinse with water after use.
Jim

[John Stankus]

I just use windex. Can't cause rust and it evaporates off all on its own.

You sure about windex not causing rust?

It’s a dilute aqueous solution of ammonium hydroxide (with probably added surfactants). Not sure chemically why that would not rust the iron in the tools.

[Russell Nugent]

Hasn't caused any rust on my tools or diamond plates over the last 2 years

[Jacob Chavez]

I've watched some videos that recommend automotive window cleaner. They claim that there is no amonia in it and has some ingredients that inhibit rust. Good info or bad? I personally don't know. My diamond stone recommend "Krud Cutter" as a lubricant. Any thoughts on that product? I ordered some of the Trend stuff. Perhaps I was suckerered, but it was only $15. I thought of it a small investment to protect the investment of the diamond stones.

[Russell Nugent]

Paul sellers has been using automotive window cleaner for years. He swears by it. I use no name windex. Rob Cosman uses water and honerite mix. Some use water. Some use wd40. Some use simple green. If your diamond stones recommend krud cutter id give that a try. Up here 100ml of trend lapping fluid is 28 bucks, a gallon of krud cutter is the same. You might be surprised how quickly you run through that lapping fluid depending on how often you sharpen.

[chris carter]

You sure about windex not causing rust?

It’s a dilute aqueous solution of ammonium hydroxide (with probably added surfactants). Not sure chemically why that would not rust the iron in the tools.

It does not react with iron or steel. So no, it will not cause rust.

[Tony Wilkins]

It does not react with iron or steel. So no, it will not cause rust.
I’m confused. Why won’t the water in windex (which is the majority of the solution) not cause rust?

eta: if there’s a chemical in it that does, I’d be curious which and how it works.

[chris carter]

I’m confused. Why won’t the water in windex (which is the majority of the solution) not cause rust?

eta: if there’s a chemical in it that does, I’d be curious which and how it works.

NH4 has a +1 charge; OH has a -1 charge. It forms an ionic bond. As opposed to some ammonia over here doing its own thing and water over there doing its own thing (like causing rust).

[Tom Bussey]

You can't run through if you do not use it

[John K Jordan]

The sds for the trend stuff looks like naphtha and hydro treated petroleum distillates
...

Several years ago someone here researched and found that the Trend fluid was kerosene and naptha. And pretty blue dye.
He didn't say the percentages but it probably doesn't matter much.

JKJ

[John Stankus]

NH4 has a +1 charge; OH has a -1 charge. It forms an ionic bond. As opposed to some ammonia over here doing its own thing and water over there doing its own thing (like causing rust).

Ammonia is a weak base, so that only a small proportion of the ammonia is in the form of ammonium. Kb=1.77x10-5 It's all about the equilibrium.

Based on the MSDS's value for the pH of Windex of 10.7 that would mean the hydroxide [OH-] concentration would be about 0.0005 M meaning the ratio of NH4+ to NH3 concentration in solution would be about 0.035 to 1. (ignoring any other equilibria that may be going on at the same time)

Iron can corrode in basic environments. It will create an Iron Hydroxide which can convert to Iron oxide. I'll have to dig around for some of the corrosion and electrochemistry texts when I get back to the office.

I am not completely up on corrosion chemistry, but this should be reasonably close on what can go on. (I'm a Physical Chemist (laser spectroscopist by training), not an electrochemist).

Then again chemistry is an experimental science...best would be to do a head to head comparison.

John


p.s. Probably the kinetics for most of these corrosion reactions is slow enough, that as long as you wipe off and dry the tool you are sharpening it probably doesn't matter what you use as a lubricant.

[James Pallas]

I learned glass cleaner (ammonia) use from an old now gone machinist friend. When he made parts for me his final clean was with glass cleaner (ammonia.) His comment to me was if you are going to paint don’t touch it, take it home and paint it today. If you are not painting take it home and oil it because “the air will rust it.” I just do it and it has worked for me for many years. I think they use ammonia based cleaners in those heavy duty parts cleaning cabinets for steel. Don’t know anything more about the chemistry. Glass cleaner has worked for me for cleaning steel for a long time.
Jim

[Rafael Herrera]

I did a bit of math and the Trend honing fluid came down to $411 per gallon at today's prices on Amazon. This has been beaten down to death on many threads here and in other fora. The SDS of that product lists its main ingredient as mineral oil. Food grade mineral oils is about $15 a gallon. Granted, they may be using some super duper refined mineral oil or some magical ingredient that makes all the difference when honing, but I doubt it. I've been using run of the mill food grade mineral oil for several years on diamond stones and oilstones. I don't have to worry about it corrosion after honing. I expect my gallon to last about 4 years, I'm not skimpy with it, YMMV.

[Charles Guest]

Lighter fluid. The can it comes in can't be beat.

[Rafael Herrera]

Lighter fluid. The can it comes in can't be beat.

$96 a gallon.

[Jim Koepke]

For lapping fluid on Arkansas stones mineral oil has been my first choice. It can be purchased in most drug stores or in the pharmacy section of grocery stores. It is often labeled as a laxative - household lubricant.

Recently A bottle of baby oil was purchased. This is a lower viscosity than the food grade mineral oil. It has very little other adulterants. It is "gentle on baby's skin" so it is probably okay on us grownups' skin.

470841 (Fred Meyer ad, a Kroger affiliate)


This product with aloe vera & vitamin E is a lightly scented & gentle baby oil that helps moisturize & soften baby's skin. This product is dermatologist and allergy tested.

At less than $17 a gallon that isn't to bad for something that isn't highly flammable and might actually feel good on rough hands.

Just ask any squeaky baby about rust prevention. :D

jtk

[Rob Luter]

I use a grinder coolant I got from the tool room at work. It has a water soluble corrosion inhibitor like HoneRite. It’s blue like Windex. A quart should last me forever.

[Luke Dupont]

I just use windex. Can't cause rust and it evaporates off all on its own.


I did that, and then found that I have an allergy to something in windex and similar window cleaners.
I have a reaction consistently, every single time I touch the stuff now.

I'm not allergic to things in general, but I'm guessing whatever harsh chemicals are in there triggered some reaction...