Gritty pivot?

[solphilos]

Hey fellas, I've had a problem with a number of slipjoints and I wanted to get your input.
With new knives I often do a deep cleaning with soapy water followed by oiling. After this and opening and closing a few times some knives develop a bit of grittiness which only gets worse with repeated opening and closing. Once this develops I try flushing the pivots well with more soapy water, wd-40, compressed air but nothing helps. I've had 3 knives meet their end this way and I don't know what's going on.

One in particular I dismantled to discover that the tang has eaten into the back spring also the pivot pin.
What is the cause of this and can it be prevented?

 

[Kbrasmodeler]

Tough to say without seeing the knives. My first thought is WD40 is not a great lubricant. I personally use mineral oil, because I do a lot of food prep. It sounds like there is some kind of grit/dirt in the pivot, so an oil flush is probably a good idea. Then again, if the surfaces in the joint aren't smooth, it might not help much.

 

[willard0341]

I use non aerosol rem oil. Drip it into the blade well wrap a paper towel around the blade (holding the knife where the oil congregates at the pivot) and open and close the knife repeatively (as much as the paper towel will allow me). Add more oil as needed and then add a little more.
Everyone has a different process, this be mine. Hope you find something that suits your needs. Obligatory knife pic. Idk if I answered your question, this is my way of exhuming buffing compound, metal shavings etc.

 

[Anothername]

My knife always gets full of bondo and paint dust at work. When it gets annoyingly gritty I’ll spray the pivot and inside of the knife really good with rem oil then I’ll fill the sink with luke warm water put the knife in it and open and close it a few times.(be careful) then I’ll blow dry or use compressed air to get all the water out. Then I’ll add a drop of mineral oil to the pivot and put at the coat of oil on the blade and rest of the knife. After doing this it’s silky smooth again. This also works for new knives to get the buffing/Metal shavings out. Ive never had a knife have such a gritty action were it would actually be damaged internally. Hope this helped

 

[Misplaced Hillbilly]

Galling is a form of wear caused by adhesion between sliding surfaces. When a material galls, some of it is pulled with the contacting surface, especially if there is a large amount of force compressing the surfaces together. Wikipedia
Galling is most commonly found in metal surfaces that are in sliding contact with each other.
I would say the soap is removing the lubricants from the wear areas, and the oil your using isn't relubricating enough. Especially if wd-40 is all you use, as its fairly thin, low viscosity with high shear rate. Mineral oil is good for knives used in food prep. Regular 3-n-1 oil is good if your not going to use it in food. That's what I use on my Klein and Imperial electrician knives. If you Google "food safe knife oil" there are allot of options, but regular mineral oil is fine.

 

[brownshoe]

Maybe your initial washing is too much or your soap too harsh. Try just using a new knife and oil when needed.

 

[lambertiana]

Use plenty of a good lubricating oil and then open/close it repeatedly while wiping the tang off regularly. You will see a lot of dark crud come out with the oil.

 

[Railsplitter]

The one brand that I frequently have a similar issue with is Queen Cutlery. The majority of the Queen knives that I've bought over the years won't lose that gritty action no matter what I do.

I've concluded that in those cases, it's a poorly finished tang that's causing the grittiness.

They are gritty out of the box though. Not something that happened after cleaning/oiling.

 

[meako]

Don't forget to open it halfway a d wipe the exposed part of the spring either side with a tissue and toothpick. I find that helps.

 

[AShearer]

WD40 is a water displacement formula. Forget the soapy water and use something like Break Free CLP or BALLISTOL. Works for me to solve exactly what you describe. Actually Balistol is so clean you can really flush a joint with a lot of oil.

 

[Misplaced Hillbilly]

Also I've had good luck with Dollar General brand spray lubricant. Unlike wd40 it is made to be a lubricant. But use caution as it comes out of the can pretty hard. I usually stick the straw down in the knife near the pivot wrap a rag loosely around it while holding it and give it a real short burst. The DG brand foams up and bubbles crud out. I used it on an imperial electrician I picked up recently. The screwdriver blade was so full of crud and was rusty in the pivot, I had to spray it closed let it soak then used the screwdriver blade on my Klein to open it. First few times I sprayed the DG stuff in it it bubbled up orange. Worked the blade and all kinda crud came out. Now its a favorite carry for me. Took only a few minutes working it open and closed and spraying it and wiping with a rag a few times. Its still a stiff 7-8 pull, but that's just a stout spring, its smooth from closed to 1/2 stop then smooth and snaps good into open.