Cleaning an extremely dirty knife

G

guitar1580

Joined
Nov 5, 2012
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I was wondering if anyone has any suggestions for cleaning a pocket knife when you wish you could take it apart, but can't. I was cleaning my Buck 315 Yachtsman over the weekend. It hadn't been used for a while, and had alot of dried out oil and dirt in the mechanism, and the pivoting spring bar seemed to have the beginnings of rust.

I cleaned it as good as I could with some Kroil, and by cleaning it in hot water and dish liquid. There was still the gritty feeling in the joint, although it seemed to be more along the sides of the spring bar, then the actual pivot point.

I soaked it good with Kroil and left it overnight. I cleaned as best as I could down inside with a small piece of scotchbrite and a toothpick, and napkins. The oil kept running out black for a long time. I put some more Kroil down inside, and dribbled a little acetone in, for the Ed's Red gun cleaning effect. If I could just have the dang thing apart for 2 minutes, I could do what I need to do, but...... can't do that. Finally after the acetone and flushing with Rem Oil, it seemed to be clean and grit free.

Any other suggestions for cleaning a very dirty gritty knife could be helpful to many. Thx.

JT
 
Sounds to me you did all you could to clean it with one exception. Don't use dishwashing liquid on your knife. I know others do, some swear by it, others will probably declare they have been doing it since childhood, and in the end it may not matter.

Dishwashing liquids can leave an additional film on your knife (ever hear the term "soap scum" or see an dish you forgot to rinse and dry?) that will attract dirt and grime. If used first, the residual leavings will probably dissolve out and be washed away, but what about the stuff you might miss? And why add water to the equation? Besides, other solutions exist that are better suited for metal cleaning.

Penetrating oils and cleaners (my weapon of choice is auto brake cleaner to blast stuff out) along with toothpicks, Q tips, etc., and a lot of patience seem to be the only choices for traditionally built knives for cleaning purposes.

I have blasted mine out, cleaned them with brass brushes and toothpicks for a couple of hours and they still cough up black/brown oil after lubricating. I keep flooding them with a light oil until it stops. After I get it to the point where I feel it is acceptably clean and working well I stop with the formal cleaning and let actual use work out the rest of the debris in the joints.

Robert
 
The only consistent method I've ever found, is to just keep working the pivots while washing (hot water + dish liquid), or while flushing with something like WD-40. Or, better yet, using the WD-40 followed by the hot water/dish soap wash & rinse (and never stop working the pivot). Rinse thoroughly in HOT water (whatever your hands will tolerate; for me, that's around ~120°F). Personally, I'd avoid using acetone, if only because it'll immediately dry up/flush out any other lube/oil in there. So long as there's some grit in there, letting the oil work for you is usually a good thing in helping to dislodge the grit particles. When it goes completely 'dry' following the acetone, then you're grinding bare steel on bare steel (with additional dirt/grit in between), and may just exacerbate the problem, creating more metal 'grit'.

I've never seen any issues with using dishwashing liquid detergent (ivory/dawn/etc), especially as it relates to soap scum left behind. There's a reason the stuff was made for washing dishes (because it leaves nothing behind, assuming it gets adequately rinsed). The 'soap scum' is an issue with actual 'soap', which contains fats/oils that make up the 'scum' (combined with minerals in hard water). Dishwashing liquid 'detergents' don't contain any such ingredients.
 
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Thx guys. I did use the acetone after the dish soap, so I'm sure that would eat any soap film. I didn't leave the acetone to dry out. I agree that may not be good. I forgot to mention above that I used WD40 to flush out the acetone and water. It actually seemed that the acetone helped to clear out the black gunk & grit that was trapped along the sides of the pivoting spring bar. The Rem oil is very light and helped to flush as well. I may try the Nano Oil soon, for lubrication needs.
JT
 
Dishwashing liquid is not soap, it's detergent-and it doesn't leave a film if properly rinsed.
Any time you use water on a knife, it should be liberally flushed with WD 40 to flush the water.
 
The reason WD-40 works so well at cleaning is the Stoddard Solvent that's mixed with the mineral oil in it, the stuff that carries the oil into all the tiny little crevices then evaporates leaving just the oil. Stoddard Solvent is the same stuff dry cleaners use in their process. It has other, more common names, such as mineral spirits, white gas, naptha, lighter fluid, and Coleman fuel. (Some of these contain things besides the Stoddard Solvent.) The stuff can clean the stripes off a zebra!


Stitchawl
 
Stich you bring up a good point about naptha. I keep it around for removing stubborn glue residue, grease etc. We use it for things like removing residual glue from expensive acoustic guitars after removing a bridge, because it will not melt the lacquer finish. Strong, but mild, I suppose. Useful for lots of things. I didn't think to pour some down in that dirty knife mechanism, but I did use the WD40. Ronsonol lighter fluid is pure naptha, but Zippo has other additives. Try a bottle. Works great for removing price tag glue, or greasy stains from finished wood items.
JT
 
My cleaning recipe for folders:

1) Brush with old toothbrush and a mixture of hot water & some dishwashing liquid.
2) Rinse under hot running tap while constantly working the pivot
3) Shake out excess water and let dry a few minutes
4) Spray the whole knife with WD-40 and put in ziplock bag for at least 30 minutes.
5) Then place the knife in an ultrasonic cleaner filled with a mixture of hot water & some dishwashing liquid.
6) Turn the cleaner on and watch the knife "explode" in grey clouds of gunk & debris, loosened by the WD-40.
7) Rinse under hot tap while working the pivot
8) If necessary repeat steps 6 and 7
9) Shake out excess water and let dry completely
10) Oil pivot pin with Nano-Oil
 
Bill DeShivs said:
Dishwashing liquid is not soap, it's detergent-and it doesn't leave a film if properly rinsed.
Any time you use water on a knife, it should be liberally flushed with WD 40 to flush the water.
Click to expand...

The brand of dishwashing/carwashing/clotheswashing and all other manner of cleaners of that type determine their actual makeup. Detergents can have soap, and almost all soaps have detergents. One cleans and breaks down particulates and the other allows the particulates to be washed away. While they don't necessarily mix, detergents and soaps often do.

Cite: The Compendium of Chemical Terminology - http://goldbook.iupac.org/D01643.html

The advent of more powerful surfactants has changed the mixtures as people can now expect a less contaminated surface after their use since the newer cleaning solutions have significantly less soap in them, which generally speaking, means less residue.

Part of my company service list is the application of commercial coatings. Almost as important as the application is the surface prep. Removal of grease, dirt and grime, oils, etc., are always a concern for metal surfaces. The classes I have taken from ZEP (industrial cleaning specialists) and Sherwin Williams Commercial Coatings division specify the recommended cleaning agents for specific types of dirt and contaminants. This is where I learned that I was incorrect in thinking that detergent and soap as purchased are two distinctly different solutions. As purchased at the local grocery, they are most likely a combination of both, with the higher soap solution being called soap and the higher surfactant solutions being called detergent.

From the ZEP class, I learned that true (non solution) commercial surfactant should not leave behind any or very little residue. I also learned how expensive they are...

With that all being said, the most readily available and tremendously affordable high surfactant solution is DAWN diswashing liquid. While most others seem to have soap or the solution itself isn't as strong, we use DAWN to remove light greasy grime and buildup to clean surfaces before we coat. We follow up with a wash of acetone for metal surfaces (regardless of the cleaner) in case the surfactants didn't finish their work of removal.

I forget how exacting folks can be here, and my original post was simply to keep him from using a detergent that actually contained a lot of soap. Most guys just buy the cheapest detergent/soap on the shelf and they will be a mix of the two and therein lies the problem.

Robert
 
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midnight flyer said:
I forget how exacting folks can be here, and my original post was simply to keep him from using a detergent that actually contained a lot of soap. Most guys just buy the cheapest detergent/soap on the shelf and they will be a mix of the two and therein lies the problem.

Robert
Click to expand...

That's a good point, Robert. There is some value in using only the more reputable brands. I've liked using Ivory liquid best (family habits via my parents, for 40+ years), and I have heard DAWN is good too. I can see how some cheaper 'dish liquids' might not be as stringent in use of detergent only. And your post made me think of another possibility, in some of the 'dishwashing liquids' that might have moisturizers or similar added ingredients, for the sake of protecting one's skin. Those might leave stuff behind too.

I have a plastic tumbler that I use on a daily basis, as my water glass. It's made of a certain very durable & unbreakable material that reminds me of nylon/teflon. It has an opaque, frosted finish that looks good and is easy to grip. The downside is, when washing it, I really have to pay close attention to rinsing it thoroughly, and also not to let the dish liquid & water sit in it for too long. The plastic and/or the finish really holds onto any scent left behind by the dish liquid, and I'll taste it too, if I don't rinse it well enough. That tumbler has become a pretty good 'test case' for evaluating how 'clean' some dish liquids are, if/when I occasionally try a different brand. :)


David
 
Thanks Robert. Yes, I did use Dawn. I've used it for years for many cleaning purposes because of it's ability to break down grease and oils. Either way, I think that using acetone, naptha, WD40, etc., after the soap and water cleaning would surely clean off any soap residue. Another thing I did while washing with the Dawn and hot water was to hold my finger over the the water faucet to blast some higher pressure jets of hot water into the mechanism, but it really seemed that flushing with the acetone and WD40 sped up the process of getting light oil to flow through and come out clean & clear.
JT
 
Obsessed with Edges said:
. I can see how some cheaper 'dish liquids' might not be as stringent in use of detergent only. And your post made me think of another possibility, in some of the 'dishwashing liquids' that might have moisturizers or similar added ingredients, for the sake of protecting one's skin. Those might leave stuff behind too.
Click to expand...

Absolutely. If they will moisturize your hands (residue!) then they have other additives that keep the moisturizing material, most likely lanolin, in solution. I didn't know until I took my classes several years ago that almost all lanolin is derived from sheared sheep wool. It is a naturally occurring oil that is quite nasty and gummy in its original state and sticks to everything. Hence, its value as a moisturizer. It is used in everything from hand lotion to leather treatments and cosmetics as it can be thinned to the point of being (for lack of a better word) moisturizing "residue". The things you learn by accident...

Obsessed with Edges said:
I have a plastic tumbler that I use on a daily basis, as my water glass. It's made of a certain very durable & unbreakable material that reminds me of nylon/teflon. It has an opaque, frosted finish that looks good and is easy to grip. The downside is, when washing it, I really have to pay close attention to rinsing it thoroughly, and also not to let the dish liquid & water sit in it for too long. The plastic and/or the finish really holds onto any scent left behind by the dish liquid, and I'll taste it too, if I don't rinse it well enough. That tumbler has become a pretty good 'test case' for evaluating how 'clean' some dish liquids are, if/when I occasionally try a different brand. :)
David
Click to expand...

I would have to say that the water glass test you have devised is a really good test. You know there has to be something left behind for you to smell it. And if it is fragrance, then that means the fragrance has a carrier as well, which is probably some kind of synthesized fat. Certainly the amount left behind is almost so small it is immeasurable, but it is there nonetheless, and designed to be left behind so your dishes will smell clean.

Since buying the ZEP cleaners I need come in amounts so large I can't use it all, I buy the unscented, uncolored, no conditioners DAWN at a local cleaning supply company that sells to commercial entities. It doesn't clean as well as the commercial products, but it is close and really leaves very little behind. I was paying about $25 a gallon, but in a real find for me, I got it at Big L@ts for $4 a quart just recently.

I always enjoy the intelligent interchange, David.

Robert
 
Getting the dirt out of a knife that cannot be taken apart is not a easy task. I've tried many methods myself and have recently started using ultrasonic cleaning which gets the dirt out of the smallest areas. Very soon I will be offering ultrasonic cleaning to all BF members.
 
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