Nihonto Oil - A Study

[Derek]

I have been using Choji oil from a Japanese sword dealer on all my swords.  I clean them with a microfiber cloth, and a bit of denatured alcohol.  All of my swords are in polish.  I started using Breakfree collector on one of my swords, and although it seems to work well at preventing rust, it is very thick and seems to attract dust.  I wasn’t sure if it was the oil or my perception.  Since I am thinking of trying other oil, I started researching alternatives.

I have been looking at oil tests available online, but found that they are geared towards guns.  The usual tests show someone treating a piece of metal with oil, spraying it with salt water, then leaving it out in the element for weeks.  This seems like a good test for a gun which may be out in the elements for a week of hunting.  My issue with these tests are that the conditions tested aren’t really what I’m concerned about.  My main worry is someone touching my treated blade (either customs, a guest, sword show, or my own negligence) then being left unnoticed and then developing rust.  I am also concerned about the oil attracting dust with sticky residue.  My other minor concerns are oil staining the shirasaya and unpleasant smell.

I developed a test based on these ideas, but focused more on nihonto.  I used the same piece of mild steel.  36” long by 2” wide.  I separated the steel into 11 equal sections, using 1” duct tape.  I thoroughly sanded and cleaned the steel, then treated each section with a different type of oil.  I left one middle section unoiled as a control.

 

 

 

I used 10 different oils in my test:

1. Choji oil from a well-known nihonto dealer in Japan.
2. 3-in-1 multi-purpose oil.
3. Breakfree CLP.
4. Hoppe’s elite gun oil.
5. Rem Oil.
6. Eezox.
7. Breakfree Collector.
8. Marine Tuf-glide.
9. Singer All-purpose Machine Oil.
10. M-pro 7 gun oil.

 

After liberally applying the oil, I wiped off any excess with a new cloth.  I then set aside the steel for 10 minutes.

I created a saline solution of 1%, which is similar to sweat, blood, and spit, any of which may end up on our swords.  I applied saline solution to each section, then wiped it with my bare thumb.  All of this was to simulate a situation where someone touches the bare blade.

I then left the steel inside on a table to measure rust.

I also put a sample of each oil into a zip-lock bag to judge color and smell.

Finally, I treated separate knives with oil, let them dry, then touched each one to judge stickiness. 

Results to come!

[Moley]

 

Results to come!

 

Aaaaaaaaaaaarghhhhhhhhhhhh

[Derek]

[Derek]

Clarity:

Some oils were completely clear. Choji oil, 3in1, Rem Oil, and Singer Machine Oil.

Eezox, and Hoppe’s are a very light yellow, almost clear.

Both Breakfree products are darker, definitely yellow.

M-pro 7 is a butter color, and cloudy.

Marine tuf-glide is brown like Soy sauce.

Once applied, all these products were not visible.

[Derek]

[Derek]

Smell:

Choji oil had a pleasant, very light clove smell.

Hoppe’s, Rem Oil, Singer Machine oil, and m-pro 7 all had little or no smell.

CLP and Collector both smell like oil, but not overpowering.

3in1 oil smells like a strong motor oil. 

Marine tuf-glide smells like plastic and light oil.

Eezox has a distinct smell.  Maybe a mixture of oil, alcohol, and soap?

[Derek]

Stickiness:

This one was very difficult to judge.  I wouold put them into three groups:

Choji oil, Rem Oil, Eexoz, Marine Tuf-glide and Singer Machine oil as no stick.

Hoppe’s and 3in1 oil as very little, but definitely noticeable. 

CLP, collector, and M-pro 7 as sticky.

[Derek]

After 8 hours, I checked the steel for signs of rust.  The untreated control had obvious rust already.  The Singer machine oil section, and the Hoppe’s section both had a large spot of discoloration.  All other sections had no visible rust.  Photos to follow....

[Derek]

[Derek]

I will update with 24 hour results soon.  I will mention that I am not affiliated with any of these products.  I am not a vendor, just a nihonto collector looking for the best product.

[Derek]

At 16 hours, the 3in1 machine oil had a small rust spot.  The sections with previous discoloration had light rust.  All other sections had no visible rust.

At 24 hours, the control was very rusted.  The singer machine oil, 3in1 oil, and Hoppe’s had more rusting.  The Choji oil, and M-pro 7 had discolored areas.  Tuf-glide had very slight discoloration.  Rem oil, Eezox, and both Breakfree products had no visible issues.

At this point, I would like to make a general observation.  It appears that a similar pattern is developing.  First, a slight discoloration begins, almost like a foggy patch.  This then escalates to a very distinct contrasting discoloration, then actual signs of orange rust. 

[Derek]

[Derek]

[cabowen]

Excellent!

[paul griff]

Thanks for sharing a very interesting and useful study.

Regards,

Paul..

[Jamie]

 

Cool idea.

I've been wondering about the break free collector.

It's hard for me however to switch from a light coat of choji or camelia oil. I don't use uchiko which is as time honored tradition as choji, but I just know it works(choji). I know the collector probably would last a long long time with no need for cleaning really but even so I'm hesitant.

Wiping the oil from the blade and reoiling has become almost ritual.

[Brian]

Excellent study, well done!

Looking forward to more observations.

 

Brian

[Darcy]

Great job. I would suggest one round of repeats side by side to make sure you can replicate the effects (i.e. that any individual good or bad result was not due to some side effect during the application of the test on that item). 

[Stephen]

one variable left off, steel not in polish, polished steel will have a finish to it thats tighter...for lack of a better word as i just woke up..;}..wheres the coffee?

[seattle1]

Hello:

Very nice research and interesting reports, though I do wonder if the rationale might be a bit off. I do not believe that the purpose of an oil or oil-like application to a blade is protection against sweat, spit or blood, but rather it is protection from the ambient contents of air, particularly moisture which can promote oxidation. It is important to keep oil, and I mean only choji oil, on a newly polished blade for some fairly short span, and then depending on the humidity characteristics of where you live, not necessarily again. As for "choji oil" the British Token Society had a short report published years ago showing that our commonly used sword choji oil had a chemical composition profile very much like automatic transmission fluid, and I suspect the difference from exactly like may have been from the addition of some aromatic.

Arnold F.

[SAS]

Excellent test, looking forward to more results!

[Derek]

Big changes at 48 hours….

Control untreated surface shows advanced stage of rust.

3in1 machine oil, Hoppe’s, Tuf-glide, Singer machine oil, and M-pro 7 all have about the same level.  I will call it medium rust.

CLP has a very light rust started. 

Choji oil is next.  No rust yet, but definitely discolored.

Rem Oil has a very light discoloration.

Breakfree collector has barely any discoloration.

Eezox has no change visible. 

[w.y.chan]

Interesting test. My observation regarding oil for nihonto is that it prevent rust, it dries quickly so it does not ruin the saya and when dried can easily be removed.

Lately I've been trying Break Free Collector with both positive and some negative result. Like some gun oil it slightly patinate the steel and depending on the condition of the polish it can have a welcome effect if the nugui became light after many years of wiping and reoiling then Break Free Collector may restore back some of the original nugui appearance and brink back some of the grains. However it may patinate the hadori which depending on the finish may not be something you want. I would recommend BF Collector on polish that is at least more than a few years old and use it once then go back to mineral oil.

 

Wah

[Derek]

[Derek]

Final update coming, which I just completed.  (36 hour)

Darcy- I will take your advice, and redo experiment, and post results here.

Stephen - I know that this is not a perfect experiment, but lend me a polished nihonto, and I will gladly try my rust experiment! 

Arnold - I appreciate your comments.  I know most of us will never have conditions like this, but I wanted to test worse-case scenario.  I always worry about my swords going through customs...

[Derek]

This will be my last check, completed at 36 hours.

Control was very rusted.

3in1 and Tuf-glide next with medium rust.

M-pro7, Machine oil, Hoppe’s, and Choji next with light rust.

CLP and Rem-oil next with heavy discoloration

Collector with some discoloration.

Eezox showing no visible change.

 

Photos to come later tonight....

[cabowen]

I picked up some Eesox the other day. It is said to dry after application. I wonder about buildup over time and how easy it is to remove. Any chance you could look at these issues at the conclusion of the corrosion test with your test samples?

[cabowen]

I picked up some Eesox the other day. It is said to dry after application. I wonder about buildup over time and how easy it is to remove. Any chance you could look at these issues at the conclusion of the corrosion test with your test samples?

[Derek]

Photos at 36 hours.  This is last in series.  I will grind down steel, move sample sites, and try to replicate.

[seattle1]

Hello Derek:

I agree. My remarks were only with reference to storage and perhaps in showing swords to friends when any occlusive coverage wouldn't be good, and probably at shows too. As for those not in the loop of proper handling it is a very different thing. I wasn't sure of the context of your experiments.

Arnold F.