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Proper Maintenance of a Knifes Edge

Started by John_B, April 22, 2019, 11:41:57 PM

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John_B

Having joined the ranks of the FVB converts I must say I think the edges of the knives I have sharpened following the process outlined in Vadim's book are definitely sharper than my free hand honing efforts. I need to visit the drug store and buy some paper for the final test. I only have receipts on hand and by feel I think the knife slides through easier than before. My wife has asked me to wear long sleeved shirts when we go out as there is a lot of hair missing on my arms and it looks like I have a condition.

To my questions; assuming I can now deliver knives that are razor sharp what instructions do I provide my customers to help them maintain the edge for as long as possible?

  • Up until today I thought the ubiquitous plastic boards and bamboo were good to use. How is maple? I always thought that if your knife could easily slice the edge of a board it was soft enough. The soft Japanese boards are very expensive and the only ones i know that have them are the two local sushi places.
  • Never use the dishwasher and hand wash and dry individually after each use.
  • Store your knives in a block with the edge up or use a magnetic strip. Do not throw them in a drawer unprotected
  • If you must cut bone identify one cheap knife for that purpose. We have a lot of people that cut the knuckle off of chicken thighs to make lollipops for BBQ.
  • Do not use the knife's sharp edge to scrape food off the board. Most people always scrape in one direction which can't be good for maintaining the edge.
  • Last use a steel before each use
Should we try and use the steel at the +1.5° to 2° increased angle used when honing? I have a steel that consists of two smooth steel rods connected at one end by an adjustable screw. I can set the angle for each side of the knife very precisely and maintain it by drawing the knife towards me while holding it vertically. Most people have the lightly serrated steels while a few have smooth steel. I do not know anyone with a ceramic rod. Which is best? I give a quick lesson on using the steel but I am guessing most are lucky if the come close half of 45° or 22.5° ± 5° or so.


Is there anything else we should be doing to extend the time between sharpening?




Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

wootz

#1
I tested an acacia cutting board, the cheapest sold in supermarkets, and it is edge-friendly. We have lots of acacia in Australia, but no maple; I can only suppose acacia is as soft a wood as maple.

The common belief is that end-grain boards are better, because the knife edge slices mainly between the ends of the wood fibers, rather than across fibers; but I haven't had a chance to test that with the sharpness tester. The end-grain boards are typically made of hardwood. I will get a thick one when we go shopping, and test on its face (end-grain) and side to compare.

Have you read Larrin's experiments https://knifesteelnerds.com/2019/01/21/does-acidic-food-affect-edge-retention/

RichColvin

Acacia (AKA, Australian Blackwood — https://www.wood-database.com/australian-blackwood/) has a Janka Hardness of 5,180 N.

Maple has a wide range of types (https://www.wood-database.com/wood-articles/differences-between-hard-maple-and-soft-maple/#hardness), and the Janka Hardness ranges from 3,110 N to 6,450 N.

These Janka numbers seem high, but compared to Lignum Vitae (19,510 N) and Gidgee (18,990 N), they are quite soft. (Of course, Balsa is the softest at 390 N.)

I use the Wood Database (https://www.wood-database.com/) for all my reference information.  It is quite good.

Kind regards,
Rich
---------------------------
Rich Colvin
www.SharpeningHandbook.info - a reference guide for sharpening

You are born weak & frail, and you die weak & frail.  What you do between those is up to you.

Ken S

John,

You bring up an excellent topic. In the ten years that I have used the Tormek and, more importantly, been active on this forum, I have seen many advances in many aspects of sharpening. Tormek has led the way in some areas. The new SVD-186 gouge jig and DBS-22 drill bit jig have reset the state of the art. The TT-50, especially the 2019 version, has raised our truing expectations. I feel that the present diamond and CBN wheels are positive steps forward in the evolution of sharpening. I hope the knife jigs and stone grader will eventually catch up.

We are also seeing major advances from other sources. Originating with Dutchman's tables, we have seen advances in bevel setting on this forum from all parts of the planet. Wootz' research is bearing fruit, a trend I expect to continue growing.

The area where we have the least control is the time between when the customer picks up the newly sharpened knife and returns for resharpening. We must educate our customers (and ourselves) to develop good habits.The early cooking TV host and writer, James Beard, summed this up very well. He stated that kitchen knives deserve the same care that the best silver receives; they are at least as valuable. I think that comment is a good lead when educating our customers.

Over the years, I have practiced several of your suggestions. They have become habits. I have two veteran wooden cutting boards. One is 12" x 18". It is a delight to use. The second, by John Boos, is 18" x 24". It is luxurious to use. I use the smaller board for the very small amount of meat that I cut. I put a quality large cutting board in the same just as valuable category as the best silver. I use my knives and cutting boards every day; I have never used my mother's silver.

Careful hand washing, drying and storing edge up in my wooden block have become so ingrained that I cannot be comfortable until I have done them. I credit Stig for teaching me to store my knives edge up in the block.

I believe the proper use of steels is the weakest link in the sharpening chain. I am definitely still learning with steels. I suspect improper use of steels degrades edges more often than correct use improves them. The nice looking steel with file teeth which came with my Henckel set twenty nine years ago has long ago moved out of my knife block and into storage. I keep it only because the unknowing person who eventually buys my Henckel knives from my estate will want it "because it matches".

I presently use two ceramic steels. The first one was a gift from Steve Bottorff. It is a very useful, well made product from Smoky Mountain Knife Works. It is also very inexpensive. It has built in triangle guides to set a correct bevel.If I had a sharpening business, I would sell them or better yet, give them to good customers with multiple knives. I think they would generate both good will and repeat business.

My second ceramic steel is one I tested for Work Sharp. It has a clever design, with alternating quadrants of smooth surface and fine teeth. The ceramic rotates in the handle. I use only the smooth parts and only with a controlled light touch. It also has triangle guides. It is considerably more expensive, however, in my opinion, fairly priced.

I could be happy with either one.

I have thought about purchasing a smooth butcher's steel. These thoughts have advanced to having it on my Amazon wish list. My inner voices are reluctant, as they are well satisfied with my ceramic steels. I still have much to learn.

Keep educating your customers. A satisfied, knowledgeable customer is your best source of growth.

Ken

John_B

Here is a picture I found of the steel I have from Razor Edge. It is called Raz-R Steel. I have had used this for many years.
https://www.razoredgesystems.com/products/steels/product/21-raz-r-steel
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

wootz

#5
My end-grain vs long-grain test did not reveal any difference.

I used pine blocks.
Knives were Victorinox SWIBO out of the box, the factory edge. I picked knives from the box that scored the same on the sharpness tester.
Initial sharpness was 125-130 BESS in both.

As a load I used the Tormek knife jig SVM-45, which weighs 320 gram, as shown on the photo, and did 100 slices, one knife on the end-grain block, and the other knife long-grain.

After 20 slices, there was no change in sharpness in either knife, the same 125 BESS.
After 100 slices, both knives scored 150-155 BESS.



Honestly, the outcome took me by surprise. I only intended to do a quick test to confirm the end-grain wood is better for the edge, but damn me if it is!
Sharpness was measured twice each time, and the results are repeating.

It is so unexpected, that deserves more systematic experimenting, giving each board 1000 cuts, and can make an interesting article for our Australian Knife Magazine:
end-grain chopping boards versus long-grain,
by wood type i.e. softwood vs hardwood and bamboo, cheap chopping boards versus expensive,
by plastic type: Yoshihiro Hi-Soft vs low-density and high-density budget plastic boards.

The next article is due in 2 months, and when out, I will copy the article to this forum.

By what my sharpness tests have shown so far, the cheap softwood cutting boards sold by supermarkets are edge-friendly, end-grain boards have no advantage for edge holding though may last longer, while bamboo and plastic boards are detrimental to the edge, as are the glass and marble.
.

van

Kindly yours

John_B

Perhaps this will make it into the myths of knife sharpening list.

Vadim, do you have any recommended articles on what steel is best and the proper use?
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

Ken S

Another excellent testing procedure, Vadim.

Ken

wootz

Quote from: john.jcb on April 25, 2019, 03:41:48 PM
Perhaps this will make it into the myths of knife sharpening list.
...

I feel the same John, we are about to bust another myth; moreover so my study must be thorough. I have all sorts of chopping boards coming, the Yoshihiro board will take 2 weeks to arrive, since I could not source it locally.
We need firm facts to advise our customers, so I am double-checking the low-density plastic boards vs hard plastic, and re-checking the bamboo; I see glass cutting boards offered even by the higher-end shops, so will include them for re-test as well.
My mates say if the end-grain proves to be myth, we should shoot a video... overall won't take longer than 3 weeks.

John_B

When I look at most end grain cutting boards I notice that the blocks are arranged in a random fashion more for aesthetics not grain alignment. Making a block where the tree rings align with the knife edge would be very difficult.

Another variable that may impact the results; It seems Western chefs chop most things while Asian chefs seem to do more slicing. The design of the knives seems to support this as well.
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

Al

Another thing with end grain boards is the glue used in them. Some resorcinol and epoxys are harder than others and could affect the edge of the knives although I would imagine this would be minimal. Quarter cut boards have a straighter grain than crown cut but I don't know if this would have any adverse effects.In cabinetmaking which was my job for the last 40+ years chisel blades always stay sharper for longer when used with the grain rather than across the grain.I also will be following Vadim's research with interest

Ken S

Al's post illustrates one of the strengths of this forum. It is easy to fall into the trap that sharpening is (only) about steel and abrasives. None of us has extensive experience in all the related skill sets. I do not have the math and science areas that members like Dutchman, Jan, Herman and others have. I do not have the many years of professional sharpening that members like Steve Bottorff have. I do not have the machinist background like Rick and others have. I do not have the disciplined research that Wootz and others have, nor do I have the extensive wood background that Al has.

Because we share our individual areas of expertise, our group total is greater than the sum of the parts.

Let's all keep up the good work.

Ken

John_B

To add to the cutting board posssible myth another thing I have read is that if you can cut the board with your knife it is ok to use it. 
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

Ken S

#14
Here is a short video describing end and edge grain cutting boards:

https://youtu.be/Zm2SeTCCa2Q

This is the cutting board I have used for more than twenty years. It was pricey, but is a joy to use.

https://www.kitchensource.com/cutting-boards/jb-ra01.htm

In the video, edge grain boards are described as NFS approved for commercial use. It did not mention whether or not end grain boards were so approved. My guess is that such approval would have been a real bragging point. In my case, home kitchen only, it would not matter.

A large cutting board is a luxury. I also have a 12x18" edge grain board I purchased at a Fisher's Big Wheel store in Green Bay, Wisconsin twenty seven years ago. I believe it is maple. It was inexpensive and has given trooper service.

I commend Vadim for his cutting board research. A good sharpener should also know about cutting boards.

Ken