Reprofiling/Sharpening CPM 3V?

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Geno
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Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 1:02 pm

I own a Spyderco Tuff and I am a bit worried about how much abrasion resistance the CPM 3V steel possesses and that it will be very hard to sharpen or reprofile. From what I have learned about the steel is that it has superior strength and abrasion resistance compared to my other VG-10 knives like my Endura 4. I am hoping to reprofile my Tuff to a 30 degree back bevel and a 40 degree microbevel, and I am planning to do this on my Sharpmaker. I have just bought the Diamond and Ultra Fine stones off of amazon and they should be here by the 6th. Will the Diamond stones have a coarse enough grit to reprofile the blade? The angle on the Tuff is a couple degrees over 40 and I am hoping to take it down all the way to a 30 and I am just nervous that the CPM 3V steel is going to be a pain in the *** to do this with.

In conclusion, has anybody had problems reprofiling or sharpening CPM 3V and if so, what am I going to be up against with trying to reprofile a 40+ degree edge down to a 30 degree with only Diamond stones on a sharpmaker?

Thanks in advance for any and all replies I appreciate it greatly :).

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Ankerson
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Re: Reprofiling/Sharpening CPM 3V?

Postby Ankerson » Sun Mar 01, 2015 1:14 pm

You are going to have a long hard road ahead of you if you think you are going to use a Sharpmaker to reprofile a Tuff.

Would be best to send it off to someone who can do the reprofiling for you setting the bevel so it would be easier for you to deal with later.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 1:16 pm

Do you think the diamond stones would at least make it bearable?

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Ankerson
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Re: Reprofiling/Sharpening CPM 3V?

Postby Ankerson » Sun Mar 01, 2015 1:19 pm

Geno wrote:Do you think the diamond stones would at least make it bearable?
No, the geometry is just too thick, would take you FOREVER.

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paladin
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Re: Reprofiling/Sharpening CPM 3V?

Postby paladin » Sun Mar 01, 2015 1:26 pm

Jim's advice is priceless...

I will go one step further...

DO NOT TRY IT!!! :eek:

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 1:27 pm

I actually just found a video of a guy doing just about the EXACT same thing as me, he is taking a Bark River CPM 3V blade and reprofiling the wide edge down using 240 grit sandpaper and a little bit of elbow grease.

yRmMCrWRiXY
sal wrote:Both our diamonds and CBN are 400 mesh.

sal
Sal himself says 400 mesh, but isnt 400 mesh like EXTREMELY coarse? I can't even find a conversion chart that reaches 400 mesh.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 1:30 pm

Maybe he meant to say grit. But other people across multiple knife forums say its about the equivalent of 220 grit on the diamond stones.

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Re: Reprofiling/Sharpening CPM 3V?

Postby bearfacedkiller » Sun Mar 01, 2015 1:39 pm

I reprofiled S110v on the sharpmaker and it didn't take too long and 3V is nothing like S110V.

Have you sharpened much S30V? They both have about 3% vanadium but the 3V has half the chromium.

I do not own a Tuff so I do not know how thick the grind is which is another factor. The more metal you remove the longer it takes. Simple as that.

I find the diamond rods (or diamond stones in general) do not discriminate much between steels so you should be fine. Progress can be slow with some of the high wear steels with the ceramic stones, especially the white ones but the diamonds and browns do well enough for me.
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sal wrote:Knife afi's are pretty far out, steel junky's more so, but "edge junky's" are just nuts. :p
SpyderEdgeForever wrote: Also, do you think a kangaroo would eat a bowl of spagetti with sauce if someone offered it to them?

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Re: Reprofiling/Sharpening CPM 3V?

Postby Surfingringo » Sun Mar 01, 2015 1:47 pm

Geno wrote:Do you think the diamond stones would at least make it bearable?
Yes, you can do it. Just turn on some music and get comfortable because you will be there a little while.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 2:03 pm

Thanks for the replies guys, has anybody here done sharpening or reprofiling with CPM 3V themselves?

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paladin
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Re: Reprofiling/Sharpening CPM 3V?

Postby paladin » Sun Mar 01, 2015 2:13 pm

good guy who's handle is razorsharp...

ask and ye shall receive...

http://www.spyderco.com/forumII/viewtop ... nd#p921096" onclick="window.open(this.href);return false;

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Ankerson
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Re: Reprofiling/Sharpening CPM 3V?

Postby Ankerson » Sun Mar 01, 2015 2:15 pm

Geno wrote:Thanks for the replies guys, has anybody here done sharpening or reprofiling with CPM 3V themselves?

Yeah, I wouldn't go near a Sharpmaker with a Tuff. ;)

Now another knife that was thinner, yeah.
Last edited by Ankerson on Sun Mar 01, 2015 3:54 pm, edited 1 time in total.

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Surfingringo
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Re: Reprofiling/Sharpening CPM 3V?

Postby Surfingringo » Sun Mar 01, 2015 2:15 pm

Geno wrote:Thanks for the replies guys, has anybody here done sharpening or reprofiling with CPM 3V themselves?
Ankerson certainly has, which is probably not encouraging since he's one of the ones telling you to not even try! :p

Edit: haha...he beat me to it.
Last edited by Surfingringo on Sun Mar 01, 2015 2:17 pm, edited 2 times in total.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Surfingringo » Sun Mar 01, 2015 2:16 pm

Double post

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Re: Reprofiling/Sharpening CPM 3V?

Postby bearfacedkiller » Sun Mar 01, 2015 2:37 pm

I wrap 220 sandpaper around my rods when I need to progress a little quicker. I use binder clips to hold it on. Just go slow when you are using a grit like that and make sure you have the paper pulled tight around the rods to avoid scratches above the bevel.
-Darby
sal wrote:Knife afi's are pretty far out, steel junky's more so, but "edge junky's" are just nuts. :p
SpyderEdgeForever wrote: Also, do you think a kangaroo would eat a bowl of spagetti with sauce if someone offered it to them?

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Sun Mar 01, 2015 5:38 pm

The reason I want to reprofile the edge is because I want to actually use my sharpmaker on it. Having a knife that I can't resharpen is a waste in my eyes.

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Ankerson
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Re: Reprofiling/Sharpening CPM 3V?

Postby Ankerson » Sun Mar 01, 2015 10:03 pm

Geno wrote:The reason I want to reprofile the edge is because I want to actually use my sharpmaker on it. Having a knife that I can't resharpen is a waste in my eyes.

The easiest thing to do is have someone set the bevel for you nice and even then you would be able to use the Sharpmaker after that.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Cliff Stamp » Sun Mar 01, 2015 11:16 pm

Geno wrote:I own a Spyderco Tuff and I am a bit worried about how much abrasion resistance the CPM 3V steel possesses and that it will be very hard to sharpen or reprofile.
The diamond /CBN rods are very coarse similar to a ~400-500 grit stone and they will cut any steel at the same speed, it doesn't matter if it is 3V, VG-10, or 1095, all of them (carbides and all) are buttery soft compared to diamond and CBN. This means that the steel doesn't make any difference, you would grind the Tuff with those rods no different if it was 3V or VG-10.

However, how you grind is critical as it has a many-to-one difference on the speed of the grinding and the wear on the stones. Here is how you do it effectively :

-use a lubricant on the rods, water will do, ideally add a small amount of detergent, really ideally use an actual cutting oil

-mark the edge in black

-grind on the 20 dps setting until the marker it almost removed right to the edge

-use only enough force to make it cut, this isn't very much at all

-go as fast as you are comfortable, this is likely faster than anyone you have seen grinding

-don't go right to the edge, the knife doesn't blow up if you do, it just wastes the steel

-don't take the knife off the stone, cut up and down

-rinse/flush the stones off once the marker is removed

-mark in the edge again

-put a coin under one side of the sharpmaker, this will decrease the edge angle by ~1/2 degree on the rod nearest the coin

-grind on the 20 dps setting (now about 19.5) until the marker is almost removed right to the edge

-this is only a tiny angle change, it will happen very fast

-flip the coin, remark the edge and repeat on the other side

-continue this adding coins (or something similar) until completed

There are many reasons why this is much faster than doing one slogging session. It is precisely because people ignore basing grinding techniques that a lot of people think this is way harder/more difficult than it needs to be.

Plus people tend to grind really, really, really slow. It is very easy to make two passes (up/down) per second, I normally do between 4-6 per second and that is cutting both up/down, however you might want to work up to that, but 2 passes per second is easy to get.

If you employ a little technique then resetting the edge on the Tuff from 20+ dps to 15 dps won't take you half an hour. If you practice that technique a little and use a coarse benchstone vs the rods, you could flatten / zero the primary grind in similar time.

Note at very high grinding speeds, 4-6 passes per second, there will likely be a little rocking of the bevel, it will end up slightly convex and you run a high risk of scratches on the main blade grind. Again, you might want to work up to that.

--

In short, the steel doesn't matter, grinding techniques are critical. And yes I have done it on many knives including 3V, 10V, 121REX, Maxamet and not only changed the edge angle but flattened entire blade bevels on knives which had thicker cross sections.

It isn't difficult, it doesn't require much skill or effort, just a little knowledge and it can be done far quicker for example than you could change a flat tire or other similar basic activity.

In fact if you actually read this post, then it is likely you could have had the first marker session completed by now.

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Re: Reprofiling/Sharpening CPM 3V?

Postby 78lilred » Sun Mar 01, 2015 11:39 pm

I have reprofiled my Tuff on Diamonds and Congress Mold Masters(I do not own a Sharpmaker) it acts the same as any other steel. Don't be afraid.

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Re: Reprofiling/Sharpening CPM 3V?

Postby Geno » Mon Mar 02, 2015 12:45 am

Isn't the coin trick flawed in the fact that the stones arent centered on the base so if I place lets say a penny under one side it will make something lets say .5 degrees less but on the other side because it is much farther away it would only make the stone .25 degrees less


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