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BehindYou
06-20-2011, 02:23 PM
just a little story and a few questions here if anyone cares to share experience/advice

ive been using j-knives and sharpening freehand on waterstones for about 6 months now, and it seems like ive kind of hit a wall.
by my standards i can get a knife pretty sharp - but with the talk on here about edge retention and wire edges etc, i feel like im definitely not up to a good standard on a broader scope.
i work in a small, busy kitchen(on poly boards) and my knife rarely makes it more than one shift before i need to go to at least 2000grit to get a decent edge back.

is it just practice practice practice until my technique reaches my needs? honestly i would rather spend money on stones or accessories than get an edgepro or other device. and at this point im definitely not going back to forschner/henckels/etc

ah, frustration

how did you all learn how to do it right?

bonus info on my setup if that helps:
tojiro dp 210mm gyuto(have a few others but this is getting the most use the past few months)
dmt xc(stone flattener, used it once to set a new bevel)
beston 500
bester 2k
arashiyama 6k
felt pad(for deburring)

thanks for reading

Benuser
06-20-2011, 02:34 PM
At which angle do you sharpen your Tojiro?

BehindYou
06-20-2011, 02:56 PM
i tried to keep it as close to the factory bevels as possible, i dont have a way to measure it accurately. i assume 12-15*?

Benuser
06-20-2011, 03:50 PM
That would be reasonable values for the VG-10 core. To calculate divide the height from stone to spine by the height of the blade from edge to spine. That is the tangens of the angle.

Eamon Burke
06-20-2011, 03:53 PM
Hmmm...sounds like a clear wire edge issue, but it is possible that the edge is too acute. What happens to your edges? Do they just stop cutting, or does the edge get tiny chips?

BehindYou
06-20-2011, 04:08 PM
i havent had any chipping issues, at least nothing thats visible to the unaided eye. it just feels duller after a few hours. for exapmple i can dice up 15 or so tomatoes just fine at the beginning of a shift, but if i take it on line for a few hours(or do some other prep - mostly veg) then go back it will hesitate to go through the tomato skin

BehindYou
06-20-2011, 04:21 PM
also i just did the paper-folding trick to approximate 11.25* and i definitely sharpen above it. im guessing based on that info that i go 15-18* normally

Eamon Burke
06-20-2011, 04:33 PM
Well, you may not want to do it this way, but I test for wire edges on kitchen knives(especially inexpensive users like that Tojiro) by abusing them. I just sharpen it up par, cut some paper, a tomato, a potato, shave some hair. Then I grab it like a framing hammer and slam the edge into a cutting board likewise. It's steel, you see, and really good quality steel at that, it should survive this kind of abuse, because that's what you are doing to it at your job anyhow.

If you notice the exact same edge degradation, it is a wire edge.

There are other ways to test an edge conclusively for a wire edge, but none that aren't fairly abusive. Ever considered removing a constant in this scenario? Yourself?

You could send it off to have someone else sharpen it, like Dave. He's not going to mail back a 1-shift edge, to be sure. If the same thing happens, then either your standards are too high(lol), or something about your work is damaging your edges. Plus you'll get a look at a fantastic sharpening job.

mikemac
06-20-2011, 05:24 PM
how about this....?
If you've been sharpening a lot over 6 months, and you're hitting a stone to touch up mid service...have you thinned the shoulder out yet? Maybe you've sharpened so much that you're forcing yourself into an ever increasing obtuse angle, and as soon as it degrades, you're left with a thick slab?

Thin the blade at your 11* mark, then add a micro bevel at 15 and see how it performs...I'm just guessing...

tim0mit
06-20-2011, 05:59 PM
I had this happen to me until i picked up a piece of balsa from a craft store and a yellow crayon (flexcut gold) from a woodworking store. Stropping will help tremendously in removing your wire edge and the setup i listed set me back all of $10

AnxiousCowboy
06-20-2011, 09:13 PM
I had this happen to me until i picked up a piece of balsa from a craft store and a yellow crayon (flexcut gold) from a woodworking store. Stropping will help tremendously in removing your wire edge and the setup i listed set me back all of $10

Can you explain what how you use this stropping setup?

tk59
06-20-2011, 09:22 PM
I would add that you should strop at a higher angle than the one you sharpen at.

Here's another method I'm going to spend some time playing with:
I'm going to use a 90 deg angle and just remove the jacked-up metal at maybe the 1k level or so and then go up in grit to 6k or so. I will then sharpen it at ~15 deg down to an edge without raising a burr. If it works, it should be the strongest edge possible, no? The toughest part will be grinding evenly across the entire edge and figuring out when to stop grinding a particular section at any given grit.

Eamon Burke
06-20-2011, 09:38 PM
tk59, if you can sharpen a knife from 90deg to push cutting without raising a single burr(as verified by high powered microscope photos from consistent areas of the edge), I'll be here.

I'll also be calling the folks at History Channel, because the Ancient Aliens people need to see what race of Star Gods gave you this power, and what it means for humanity.

Eamon Burke
06-20-2011, 09:47 PM
Can you explain what how you use this stropping setup?

Think of stropping on balsa like a making your own stone. Bare Balsa would be considered 0 microns, because it is so smooth. You pick a micron size, put that kind of compound on the balsa, now it's a "stone"(one you can't push a knife edge-first on or get wet) at the micron size of the compound.

It works brilliantly.

However, stropping on a slick surface like balsa can remove burrs, but only by abrading them down with the power of the compound. Leather/felt/etc has enough friction and "grab" to pull at the metal, it is basically more aggressive. Imagine being pulled along a sidewalk(balsa), vs being pulled along a giant concrete coated mattress(leather).

Don't tell anyone, but I've used compounds and balsa to make faux stones I've used on Kata-ha knives to great effect. You just get lots of compound on your fingers and an ugly polished finish.

AnxiousCowboy
06-20-2011, 10:09 PM
So what is Flexcut Gold crayon?

Any pictures of your guys' stropping setups and videos of you in action?

Eamon Burke
06-20-2011, 10:15 PM
The Gold crayon he referred to is a buffing compound, commonly sold at hobby and hardware stores, which are pretty low grit for stropping, compared to what is available. You can get "Jeweler's Rouge" at higher grits, but the problem with these is that they are created and optimized for powered applications, where you have lots of inertia behind it. Compounds (http://www.chefknivestogo.com/choxd4oz.html) sold (http://www.straightrazordesigns.com/index.php?main_page=product_info&products_id=404) specifically (http://www.japaneseknifesharpeningstore.com/product-p/dudiasp1.htm) for knife sharpening work CRAZY fast, even when working by hand.

goodchef1
06-20-2011, 10:55 PM
Edges in a commercial kitchen takes a beating and a half. I have never went through a full shift without at least honing and I've done it with at least 12 different steels from good makers. I think think you are doing well if you can get by throughout a shift. Not to say that it should be dull.

if you are looking for the exact same edge at the end of your shift as when you started, that is not going to happen. edge retention is at this point subjective to a lot of variables, ie: length/number of cuts, what is being cut, force on cutting board, type of cutting board, lateral impact, etc. etc.

get a digital microscope or powerful magnifying glass to inspect your edges before and after shift and during sharpening as just one way to learn and get better. :D

tim0mit
06-20-2011, 11:07 PM
I like the flexcut gold precisely because it is a high grit level. It leaves a toothy edge that will last me the whole shift. I cut the balsa down so it works in a rubber steel rod stone holder and will thus fit in my knife roll.

tk59
06-21-2011, 12:06 AM
tk59, if you can sharpen a knife from 90deg to push cutting without raising a single burr(as verified by high powered microscope photos from consistent areas of the edge), I'll be here.

I'll also be calling the folks at History Channel, because the Ancient Aliens people need to see what race of Star Gods gave you this power, and what it means for humanity.

Yeah, I don't expect it to be completely burr-less the entire length of the edge, lol. I also expect it to take quite a while (totally impractical). It's more of an interesting exercise. Frankly, I'm pretty confident that I can achieve an edge that push-cuts paper, etc. this way. I doubt I'll have the patience to reach falling through tomato type sharpness. I doubt this type of edge would be much more robust that my normal edge. That's what I love about this forum. This is pretty much a useless exercise but some of us are actually interested. Thank you, Eamon.

stevenStefano
06-21-2011, 06:31 AM
This has happened to me a few times with VG10 knives. I think I simply wasn't spending enough time in the mid-range stones and was trying to rush the sharpening a little. I also thinned mine to 10 degrees then put a 15 degree microbevel and it made a massive difference in performance.

Citizen Snips
06-21-2011, 12:09 PM
i would say concentrate more on a microbevel rather than worrying about stropping but with VG-10 it sounds a lot more like a wire edge.

something similar happened to me like 8 months ago. i found that my edge was not as sharp as i wanted and it would deplete very quickly. after i found the wire edge and how to remove it, my sharpening got 10x better and i started to understand what i was really looking for with my edge quality. from there i found the tricks to be able to keep my edge for extended periods of time.

its all part of the process of learning to sharpen correctly. my first 3-4 months was just learning muscle memories for the actions needed for sharpening. after that was tweaking and learning due to the desire to get a perfect edge. the drive to get better and to get a perfect edge is what brings us all here :D

BertMor
06-21-2011, 09:28 PM
Part of the problem is the poly board. It doesn't matter what knife you have or how good the heat treat is. Cutting on poly for an entire shift will really abuse the edge. Try keeping it at 18* per side, going more acute is just asking for less edge retention. Or jettison the poly's and get a Sani-tuff or end-grain board

Salty dog
06-21-2011, 09:44 PM
especially if you're a rocker.

BehindYou
06-22-2011, 09:53 AM
thanks to all for the suggestions! im definitely still pretty new at this and i appreciate all the experienced folks here sharing info and suggestions
i think im gonna try thinning and doing a microbevel. i was considering sending it out for a pro sharpening, but the tojiro has pretty much achieved beater status through a lot of trial and eror already. my next knife purchase is gonna get sent out straight away
as far as durability, im not expecting miracles, but if im not going for the perfect edge than what is there to look forward to/work toward? :)
re: cutting boards - does anyone bring in their own to work? in my case its an issue of having nowhere to store one where it wouldnt get thrashed by everyone else in the kitchen. and itd be a pita to carry it in and out every day(especially since i walk to work).
also the only rock-chopping i do is the occasional few extra passes through minced herbs. buuuuut i know that my overall cutting technique plays a part in the life of an edge and im always trying to improve that as well

Citizen Snips
06-22-2011, 10:35 AM
i keep a large boos wooden cutting board at work. i put it away when i leave and everyone else knows not to touch it while im gone

in all seriousness though, i dont think you need to bring a cutting board to work, its just that those boards you have there are a little harder on knives. i remember using those a long time ago and they were murder on my old cutlery. its not a necessity but it might help. i dont like my knives to touch plastic ever but when doing fish i have to because sometimes my wood board is not big enough and i dont like doing proteins on the wood. in an ideal world i would use a full table butchers block :D