Review: Navy K-631 Lock Back Knife

Hey Old4570,

Very nice knife, I like the G-10 scales better than the plain Stainless Steel on my old Spyderco.

I know that I've had this knife for over 20 years. I bought it just as Spyderco started putting the pocket clip holes on in the "point up" configuration.

I'm pretty sure that I paid over $100 for it. Great steel, it's a TANK.

Not my favorite knife though, it's slick, not hand friendly. But it will take an edge, this puppy will shave hair!

Pardon the blurry image, it's a bit of a "self portrait"

Hehe, that's the old version of the C07P - my favorite EDC knife for years and still one of my all-time favorites, even though I no longer carry it. Good memories, awesome knife.

I like the blades on the navy knives but the G10 always seems unfinished.

Yeah, I know what you mean. I always wonder if maybe they do it on purpose to appease their (Western) OEM partners or something but I don't think I've ever seen a Navy knife that had flawless G10 handles. My K602, K603 and K607 are probably the worst, while the G10 on the K608 actually looks and feels okay.

They do make some rather nice stonewashed (ie. G10-less) knives though. I have a K506 or K505 (not sure right now) and there's a stonewashed, framelock version of the K602 that I've had my eye on for a while now.

Nice pics parkerdude

Am I just a weird geek or what but I like to see Lights, knives etc. used!

Those pics of "well served" stuff from "way back" somehow make me smile... Can´t really tell why.

Maybe I´m just sick´n´tired to see those shelf-queen collections from certain forum, that have never been outside yet are worth of a small fortune.

Last picture = wow

But yeah , if they dont shave , there not sharp ...

Sharp knives,

My dad was a butcher by trade, and ALL of his knives were super sharp.

One day, he was working up on a step ladder inside a closet. He needed a knife, and asked for my Boy Scout knife, which I opened and gave him.

After trying to make the cut, he angrily looked at me and told me to NEVER give him a dull knife again. He stuck that knife into that closet's door jam and broke the blade off. Needless to say I was pretty upset.

After he finished that task he took me aside and explained how important it was to take care of my tools and that knives should be kept sharp.

Then my Dad told me to get my cap, we needed to go to the store.

We went and bought a brand new Boy Scout knife. Dad took me home and got out his sharpening stones, and taught me that day how to sharpen a knife.

I have never forgotten that day, and I have NEVER had a dull knife in my pocket since. I never abuse or dull my sharp knife. I will use appropriate knives for the job at hand.

I hope that all of you enjoy the use of a RAZOR sharp knife. I think that it is a simple joy in life we should all know.

I teach all of the youngsters around how to sharpen knives if they show interest, that they might feel those pleasures too.

p.s. recently my mother in-law gave me her father's straight razor. I'm learning how to sharpen it and I'm shaving with it 2 - 3 times a week. It's pretty cool, and a little scary.

later y'all,

I have a sharp Bowie , and I have tried to shave with it ...

I think I need shaving cream ... Its sharp enough to cut of layers of skin , but the facial hair is a little thick , and getting heavy handed could lead to a trip to the hospital to have my face sown back ... So I may stick to the machine

That's not a Police model. looks like a SS Endura.

Hey Old4570,

I'm subscribed to this thread , so I keep returning...

To quote your original post...

"I was also impressed by the factory edge on the blade , it really cuts well . This knife may have had the best factory edge of any knife I have owned , and I own a lot of knives . It seems to have micro serrations , so while it shaves hair off my arm , I have better , sharper shavers , but this one really cuts . It cuts paper like no other knife I own , even ultra sharp blades can catch and tear paper , but micro serrations stop this from happening . You can feel them when you run your fingers over the edge , and they come from the way the blade is ground / sharpened . [ Im going to hate loosing them when I re-sharpen ] ", perhaps I can help.

You sound like an interested kinda knife guy, I'd like to share a few things that I've learned about sharp things. As I said earlier, my dad was a butcher by trade, and he taught me how to sharpened a knife pretty well.

From your comment about "micro serration's", I revisited my diamond sharpener. I remembered that when using the "fine" side, I got a fine serration, like you said, on the blade. (As an aside, I have noticed scalpel blades are ground with those "micro serration's", no doubt for a reason.


What I wanted to share was that my dad had a sharpening "steel", like the one's you can get with some kitchen knife sets, except dad would take the sharpening stone and polish the "steel" end to end until ALL of the grooves are gone. It's a real PITA, but you only do it once in your life.



From that point onward, I use the steel almost every time I use the kitchen knives. I only actually sharpen the knives with abrasives 2 - 3 times a year.

"Steeling" a knife reforms the "V" shaped edge without removing any metal, GREATLY extending the life of my knives. You older knife guys might remember the "old school" butchers using them.

I'm telling you, if you add this step to your knife sharpening method, you will be rewarded with sharper and easier to keep sharp knives the rest of your life.

I liked this one enough to buy its smaller brother , but I dont expect to get it till after Christmas ..

Damn so much stuff stuck in the Christmas crunch ...

Was kinda wishing the knife was here already , some batteries , some flashlights , whole bunch of stuff ...

Just glad the Press y I ordered for my Brother arrived before Christmas and not after

I use a diamond hone , and then use a steel rod to finish the edge ...

I would like to find a really mild 1inch steel rod [ one day - I will go to one of the steel warehouses-suppliers and buy a foot long 1inch mild steel bar = really soft steel ]

Steel on steel = Fantastic I have even used Chromed [ finish ] screw drivers to work the edge ..

I just get the feeling softer is better [ could be wrong ] maybe have the rod chromed , ???? [ Well , I want to try mild steel , the piece I have seems to work ]

What is the smaller brother? I've been waiting for a FFG knife similar to a Delica.

There are smooth Steel’s Ive even seen glass rods … but those are rather fragile

Nice knife, quite smooth to open, but the handle is a bit too long for my taste and hand.
And as I said in an other thread, mine came really “dirty inside”.

Ok , thats dirty !

RP7 WD40 , should clean them out !

Hot water and soap did it pretty well.
I don’t like the smell of WD40 but it is probably a good suggestion for those who do not mind its smell.

I have not dismantled my recent Navy K-502 yet. I don’t know why but my torx tools are always loose on every knives torx screws. I don’t like this and don’t want to risk to destroy the screws print (head ?).
Torx sizes are supposed to be international sizes or is there a metric sizes and another in inches sizes ?

Not sure how good the Chinese are at international standards ?

Metric or imperial …. Torx - Wikipedia looks like both …

I bought two of these when I realized that the clip can be swapped from side to side. One for each hand. :slight_smile:

Haven’t actually taken them anywhere though. EDC is a Leatherman Kick (and Micra) and a G704.

It doesn’t look like dirt…

The “black stuff” on the pivots looks to me like Moly Grease - that is a high-pressure lubricant that just happens to be black. Pure Moly, or Molybdenum Disulphide, is a very fine, black powder that penetrates and sticks like hell to any surface. It is a common additive to grease to improve it. Removing it and not replacing the grease will make the action of the pivot sticky.

Of course, I do recommend cleaning and re-lubricating folders as a part of regular maintenance, but the pivots need grease or high viscosity oil. WD-40 is not really a lubricant, it is a solvent, and doesn’t provide lubrication or corrosion protection once it dries.

Using Moly Lube on the pivots is a good choice as it’s very good lube. It doesn’t take much, the pictures show about 2x what is necessary from the factory, so you can get enough to maintain 1000 knives for 10 lifetimes at the auto parts store for a few $$$.

The only issue is that it’s black, so just be careful when carrying in your white Chinos.

It’s no problem for me as I wear black jeans, but all the gasoline keeps the grease build-up down anyway…:slight_smile: