knife trouble

D

Don Joe

Joined
Aug 12, 2016
Messages
159
i've been trying to sharpen one of my knives on my smith pull through, buts it taking forever. it always takes forever but this time its worser. i thought it had something to do with the black coating (maybe?) but i was told here it wasn't true. now I'm starting to think that maybe i heated the blade up too much sharpening it and when i went to wash it i cooled it too fast and hurt the temper and made it too hard. wonder if heating it in an oven would make less hard as i was told by a friend it would make metal softer, but I'm afraid it will melt the plastic handles.

any thoughts are appreciated. :thumbup:
 
Never use pull through sharpeners. They ruin blades and do not sharpen properly.

You cannot generate enough heat by sharpening to ruin steel tempering.

Black coating can mean a lot, but neither should impair sharpening much.

I suggest you get a sharpening system such as Spyderco Sharpmaker or Lansky Sharpening kit...you'll get any knife hair-popping sharp in minutes.
 
...with great restraint I will reply to this as though you are an honest person asking a serious question. First, the coating will not affect sharpening, but as you were told elsewhere the other day, pull through sharpeners are not a good way to sharpen. Secondly, putting a knife in an oven will truly ruin it. Also, the heat you'd have to generate with the pull through sharpener to mess with the temper would mean you'd have to use much more force and speed than any person is capable of.
 
AdamFuzzyballs said:
...with great restraint I will reply to this as though you are an honest person asking a serious question. First, the coating will not affect sharpening, but as you were told elsewhere the other day, pull through sharpeners are not a good way to sharpen. Secondly, putting a knife in an oven will truly ruin it. Also, the heat you'd have to generate with the pull through sharpener to mess with the temper would mean you'd have to use much more force and speed than any person is capable of.
Click to expand...

ok, oh boy well thats a relief. glad to hear i haven't ruined it! i probably just wore out my old pull through. had it for years, its probably just ready to retire.
 
Corwyn_bv said:
Never use pull through sharpeners. They ruin blades and do not sharpen properly.

You cannot generate enough heat by sharpening to ruin steel tempering.

Black coating can mean a lot, but neither should impair sharpening much.

I suggest you get a sharpening system such as Spyderco Sharpmaker or Lansky Sharpening kit...you'll get any knife hair-popping sharp in minutes.
Click to expand...

those sharpeners sound nice! i don't think I've ever had a knife hair popping. usually just get it to where it will cut paper. ill give those a looking. would love to get one to shave hair. thanks buddy :thumbup:
 
Don Joe said:
those sharpeners sound nice! i don't think I've ever had a knife hair popping. usually just get it to where it will cut paper. ill give those a looking. would love to get one to shave hair. thanks buddy :thumbup:
Click to expand...

If you're willing to invest the time and money, I'd recommend you replace your pull through with a Lansky sharpening kit.

This is a great little sharpening kit that can put hair-popping edges on knives with relative ease. I've gotten some extremely sharp mirror polished edges with mine (and my extra fine stone that I bought separately). You can find comprehensive tutorials on youtube for how to use this.

Many people are telling you that pull through sharpeners are bad, but as far as I've see, none have told you why it is that they're bad.
If you look at your knife under a (very very powerful )microscope, you might see little chunks of carbon 'floating' about in the rest of the steel.. Those are what make your edge hard, and allow it to keep and hold a sharp cutting edge. Now, if you look at your pull through, you'll see two little "blades" made of carbide that you pull your knife through. The problem with using this system is that when you pull your knife through the sharpener, what's essentially happening is the chunks of carbon (the hard part of the blade) in your knife blade are being ripped out, leaving behind the softer steel and creating micro-serrations, which means that if you look at the edge under a microscope it'll be jagged. Your knife may feel sharp, and it may cut well, but the softer steel will get dull much, much quicker than if you hone the blade with a stone, which sharpens the carbon chunks instead of ripping them out.
(please correct me if this isn't true, I only learned the specifics on this a few days ago).

If you have any more questions, or want to discuss and learn more about knives, feel free to ask!
 
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Stop Andy, I nearly choked on my whiskey... Good luck to you Don Joe; DMT diamond stones, a Spyderco Golden stone, Ken Onion Work Sharp... all goodies when it comes to sharpening and edge maintenance.
 
I'm guessing it has something to do with the black coating changing the molecules of the steel. I bet it made the steel melt a little because you used the pull through sharpener too fast.

I bet if you go slower, then dunk it in water after each pass, it will be ok. You'll be popping hairs with that edge in no time. :thumbup:







.
This can't possibly be for real. :rolleyes:
 
Even this little inexpensive Lansky system will get you decent results. This was what I first used when I got into knives, but I've since moved onto other methods. Good luck to you!

Lansky 4-rod Turn Box Crock Stick Sharpener (LCD5D)

Alex
 
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Don Joe said:
i've been trying to sharpen one of my knives on my smith pull through, buts it taking forever. it always takes forever but this time its worser. i thought it had something to do with the black coating (maybe?) but i was told here it wasn't true. now I'm starting to think that maybe i heated the blade up too much sharpening it and when i went to wash it i cooled it too fast and hurt the temper and made it too hard. wonder if heating it in an oven would make less hard as i was told by a friend it would make metal softer, but I'm afraid it will melt the plastic handles.

any thoughts are appreciated. :thumbup:
Click to expand...

Don Joe-

Please don't cook your knife, very bad idea.

I use a Sharp Maker sharpener with success. It is relatively inexpensive, small and portable, easy to use, and effective in sharpening all kinds of blades, hooks, bits, screwdrivers, scissors, etc.. It might cost a little more than some but because of the versatility I think it is well worth it.

Here is the first of a four-part video by the maker of the Sharp Maker, his first knife product, where he discusses the history of cutting edges, and how to sharpen them. I think you will enjoy it and learn a great deal about sharpening a knife blade. I wish someone had shown me this video when I started getting serious about knife sharpening.

https://www.youtube.com/watch?v=GB0r6GvESGg

I wish you the best of success.
 
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I would suggest you get a Norton India Stone (the 1" x 2" x 8" version) and begin to learn how to sharpen freehand. It will have coarse and fine sides. I know you don't buy high end knives (aka super steel), so this bench stone should work really well. They run under $20. The V type ceramic sharpeners work okay for touch ups, but not so good if you need to sharpen a lot. They are very simple to use. I generally sharpen my Vic SAKs on the Norton. A few passes and I'm ready to go on the fine side.

Freehand sharpening is not hard, but you need to pay attention to the approximate angle you sharpen at and be consistent between the two sides. I use WD-40 as my lubricant with the Norton India Stone.

For "hair popping" sharpness, you probably need diamond bench stones or perhaps a ceramic to use after the Norton. I use DMT ones. Many get their edge pretty sharp and then strop for the final "hair popping" sharpness.

Dump the pull through sharpener. The only time I would use such a sharpener is for cheap kitchen knives where I am using a knife and need a real quick tune up. They typically are very soft steel.

I figure you don't want to spend a lot of money at this point, so that is why I suggested the Norton. The DMT bench stones are fairly expensive. The 8" duosharp run around $130 each these days.
 
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Smith's makes a decent, 2-stone guided sharpening system that can be had for about $20 at. It's really easy, and while I've never pulled off a shaving sharp edge with it, it makes very useable working edges in a couple of minutes.
 
I can't be sure, but what the OP started with has been true to my experience with a S&W knife. I carried a CH0030 every day for 5 to 6 years until very recently. I had a pull through as well and I noticed that over time the edge it would take had seriously degraded. I was thinking that the heat treat was off in my particular blade as I took it to the Rockwell tester and it clocked in at 56- 57 HRC. I may try to salvage it on proper stones but I've been EDC'ing a sweet Boker+ Urban Trapper that puts the old S&W to shame in every way!
TLDR - I also noticed that repeated carbide sharpening lowers the top level sharpness.
 
Pull through sharpeners are not very effective. If you hang out here and read more you would learn this. Also, the search function would have told you this as well.
 
Throw the pull through sharpener in the trash can and those of you new to the forums pointing folks in the direction of non-BF dealers with names and links is a big no-no that one of the mods will come along and gig you for I would suggest you edit your posts. Not being a jerk just trying to save you some grief.
 
Don Joe said:
i've been trying to sharpen one of my knives on my smith pull through, buts it taking forever. it always takes forever but this time its worser. i thought it had something to do with the black coating (maybe?) but i was told here it wasn't true. now I'm starting to think that maybe i heated the blade up too much sharpening it and when i went to wash it i cooled it too fast and hurt the temper and made it too hard. wonder if heating it in an oven would make less hard as i was told by a friend it would make metal softer, but I'm afraid it will melt the plastic handles.

any thoughts are appreciated. :thumbup:
Click to expand...

Hi,
What knife is it?
Does it have "vanadium" carbides? vanadium carbide is harder than tungsten carbide and will cut it (dull it)

do you clean the sharpener? which model is it?
If it has a screw there is a chance you could flip/rotate the carbide and keep on sharpening.

Try sharpening a paring knife from your kitchen to see if the pull through still works.

If you've been sharpening this knife for years,
it might be that you need to thin the knife behind the edge,
thin down the shoulders,
so the pull through sharpener doesn't take so long.


If its a simpler steel (not high carbides), a $1 stone from dollar tree is a pretty good deal :) or similar stone from lowes/ace hardware preferably siliconcarbide/crystolon (harder abrasive)


If you're shopping on ebay, there have been crazy prices on sharpening stuff lately, generic versions of edgepro... even lansky/kme with diamond stones ... benchstones, all for under $8, but shipping time is a couple of weeks



More info on tungsten carbide pull through sharpeners below
You can see some magnified pictures here
Long term carbide scraper use
This guy flattens his carbide scraper to improve results, that is hardcore :D
The 6 dollar carbide scraper and you! (with micrographs)

Steve Bottorff gives a short review of a few, the rest of his free book also makes good reading eventually Knife sharpening with slot devices

This review and video explain how to make the best use of pull through sharpeners
Sharpener Review : Everyday Essentials Two Stage Sharpener
:) video on how to get the good results
[video=youtube;lgQKgqQEj6g]https://www.youtube.com/watch?v=lgQKgqQEj6g[/video]
the discussion thread is Tungsten Carbide Sharpener it links other videos, like, this next one,
How to get the bad results (press harder), starts of with very sharp knife, pulls through a few times, its still very sharp, then presses harder, and its snag city
[video=youtube;U9XIO4gVMeQ]https://www.youtube.com/watch?v=U9XIO4gVMeQ[/video]
 
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