Best way to sharpen a knife

[dcarch]

HowardLi, I am very puzzled by why you are so insistent in recommending to a beginner to use a belt sander to sharpen an expensive knife.

I am surprised that you feel that for a beginner, it is easy to correctly put on a convex edge on a knife.

I am surprised that you feel a beginner has no problem in telling when a critical edge can be permanently de-tempered and destroyed on an electric grinder.

I am surprised that you are unfamiliar with the fact that most sanding belts are printed inside the belt with directional arrows to run in only one direction.

As a machine shop teacher in a college for many years, my experience in what beginners can do with motorized machines are very different than yours.

As a long time part-time knife maker, I know how difficult even for me to do things right with a belt sander.

For your pleasure, one of the many knives I made just for fun, with a convex edge.

dcarch

[Country]

Nice work, dcarch. What did you use to cut the cold saw? And did you anneal, and re-harden and temper, or do all the work cold? But, why did you leave the teeth on the end of the knife?

Questions, questions, questions...

[David A. Goldfarb]

I think the teeth on the end of the knife are cool. Maybe they're not very practical, but they're a trace of the knife's past life.

[dcarch]

Thanks guys.

I cut the blade out from the saw on a wet tile saw but with a metal cutting wheel. I need a very tough edge, but not a very hard edge, so I didn't need to harden the already hardened tool steel saw blade. the grinding and rough sharpening were done with an angle grinder, again, with water. It does keep a sharpe edge very well.

I left the saw tooth on for mainly two reasons, one is to use that end of the knife to jaccard tenderize meat, the other is to use it as a scraper to form/shape sauce for interesting plating looks.

I had no idea what to do with the hole that came with the saw blade. May be I can use that as a finger hole and learn to swing the knife like a cowboy with his six-shooter.

dcarch

[rotuts]

fantastic table saw knife!

[HowardLi]

HowardLi, I am very puzzled by why you are so insistent in recommending to a beginner to use a belt sander to sharpen an expensive knife.

I am surprised that you feel that for a beginner, it is easy to correctly put on a convex edge on a knife.

I am surprised that you feel a beginner has no problem in telling when a critical edge can be permanently de-tempered and destroyed on an electric grinder.

I am surprised that you are unfamiliar with the fact that most sanding belts are printed inside the belt with directional arrows to run in only one direction.

As a machine shop teacher in a college for many years, my experience in what beginners can do with motorized machines are very different than yours.

As a long time part-time knife maker, I know how difficult even for me to do things right with a belt sander.

For your pleasure, one of the many knives I made just for fun, with a convex edge.

dcarch

What point are you trying to prove, that one needs professional training before attempting to use a belt grinder to sharpen a knife?

[dcarch]

I don't have a point to proof. I am not disputing the fact that a belt sander is a great tool for sharpening knives. As I said, I use one and most professionals also use belt sanders in their shops.

I am just wondering if you have overlooked the important fact that the OP is a complete beginner with a good quality knife asking for advice to sharpen his knife. Frankly I have never heard of recommending a belt sander for a rank beginner starting out to sharpen a good quality knife.

dcarch

[dcarch]

fantastic table saw knife!

Thank you. It is not easy to find a good high-carbon steel cleaver. Everything is stainless steel nowadays. I had to make my own.

dcarch

[Dakki]

A work of art.

[rotuts]

A long time ago ... lets say the '70's or so of 1970's just a guess

I knew some people that went to car junk yards and got steel from really old cars ...

the steel that was not the coil spring but the laminated (just belts of steel ... not Japanese laminations here ...) of the "spring" of the car

4 per car but many laminations per wheel

that made great knives at that time.

cant say about that steel now. probably has fermented corn husks in it now ...

[Dakki]

Knifemakers in Oaxaca still use old leaf springs, rotuts. I think the one I visited told me it was similar to working with 1060.

[rotuts]

well I dont know what 1060 is. please enlighten

but I do now "old" those springs you mentioned were really good

today's springs?

id love to learn more.

[HowardLi]

fantastic table saw knife!

Thank you. It is not easy to find a good high-carbon steel cleaver. Everything is stainless steel nowadays. I had to make my own.

dcarch

http://www.japanesechefsknife.com/ChineseCleaver.html

At least half of the cleavers on that page are carbon steel.

[Dakki]

SAE 1060 is a grade of steel. In this case you can read the chemical composition just by looking at the number. Three-digit numbers indicate stainless, four-digit are carbon and alloy. Anything that starts with "10" is plain carbon (with a small amount of impurities and some manganese allowed) and the last two digits indicate the amount of carbon.

So 1060 means it's carbon steel with .55 to .65% carbon by weight.

Joe Talmadge has a neat knife steel page (at least I think it's his) that has a lot of resources if you're interested.

[HowardLi]

If it helps, I'm a mechanical engineer.

[Edward J]

dcarch,

Hey, I know that saw blade!!!! It's a circa 80's sears Craptsman "kromedge" plywood blade! Many's the time I cleaned off that blade with Easy-Off! so it wouldn't smoke when I cut a half sheet of ply with it.

I got another one and a matching dado stack, if you're interested....

Nice work! I like the brass "ferrule", hydraulic coupling?

[dcarch]

A work of art.

Thanks!

Knifemakers in Oaxaca still use old leaf springs, rotuts. I think the one I visited told me it was similar to working with 1060.

I have made knives with metal files. Very difficult to work with, but you get a very sharp knife at the end.

I may get some 1095 steel to make a chef knife.

dcarch,

Hey, I know that saw blade!!!! It's a circa 80's sears Craptsman "kromedge" plywood blade! Many's the time I cleaned off that blade with Easy-Off! so it wouldn't smoke when I cut a half sheet of ply with it.

I got another one and a matching dado stack, if you're interested....

Nice work! I like the brass "ferrule", hydraulic coupling?

I still have many old non-carbide blade. You should try to make one yourself. Nice steel and the right kind of thickness for a knife. The brass "ferrule" was a plumbing coupler.

dcarch

[rotuts]

many thanks for the education and pointers! bookmarked for the future.

[Dakki]

No problem. I could go on about this stuff all day, and I'm sure some of the other posters in this thread could too, but we're getting further and further off topic.

Looking over my previous reply, I should clarify the following (before someone jumps down my throat...):

SAE grades are also sometimes called AISI or AISI/SAE. There are historical reasons for this but, who cares. It's just a naming convention.

There are five-digit SAE grades. These are alloy steels that follow the same four-digit convention I explained above, but have 1% (nominal) carbon by weight or more, so xx100 means they have 1%, xx120 is 1.2% and so on.

Structural steels (used in construction) follow their own naming convention, indicated by an A followed by two or three digits.

Tool grade steels also follow their own naming convention, one letter followed by one or two digits, such as A1, D2, H13 and so on.

All of the above applies in the USA and countries in their industrial sphere. Other countries apply different standards such as DIN (Germany), JIS (Japan), etc. which can get confusing. You'll be able to find an identical standard (or close enough) most of the time. Google tells me SAE 1060 is JIS SWRH62B and DIN C60.

[Country]

Knifemakers in Oaxaca still use old leaf springs, rotuts. I think the one I visited told me it was similar to working with 1060.

Many of the Gurkha, or Khukuri, knives from Nepal are made from truck springs. The steel is pretty tough and it's a useful knife for some things. Especially for limbing small trees after they've been cut.

This link is a pic of virtually the same knife I have - blade, bolster, and handle. But the scabbard is much nicer.

[rotuts]

I have a very similar knife i got in India. not as nice a handle but with those two little ones included

[dcarch]

Motorized planner blade steel is probably very good steel to make into a knife.

dcarch

[Country]

Joe Talmadge has a neat knife steel page (at least I think it's his) that has a lot of resources if you're interested.

At the beginning of this thread was a link to a 2003 Q&A on knife sharpening and maintenance and Joe Talmadge dropped by to answer a question I had. It's something I hadn't figured out and here's the question I asked...

In all my years of sharpening knives, after years of sharpening a knife, the tip always gets blunter and blunter as time goes on. In other words, I can take a perfectly good boning knife and after ten years or so the tip is close to a ninety degree angle to the heel. It's still sharp, but I've lost the point. What am I doing wrong?

Here's link to Q&A page. Back then I was "Nick" (at top of page) and after I get done blathering I ask the question. Scroll, or page down, about halfway and Talmadge pops in with an answer. He also gets into dry vs. oil using stones.

Thought I'd post this in case others have had problems with blunting the tips of knives. I sure have - from jack knives to boning knives.

[HowardLi]

Couple of things to report:

dcarch, I owe you an apology. There are indeed sanding belts which are directional. However, my Trizact sanding belts are bidirectional. C'est la vie.

Second, sharpening a knife with a belt sander is extremely easy. My first knife (just did it, actually) came off the sander shaving sharp... so now I have a really nasty bald spot on my forearm. All the other tests are fine - tomatoes, hanging paper, etc.

Only thing I note is that you need to be very careful near the tip with coarse grits as it can get rounded quickly.

[paulraphael]

If you know what you're doing, a belt sander is great for major repairs and for sharpening stouter, softer European knives. I wouldn't recommend them for the thinner or harder Japanese knives. You're not going to get the kind of edge that's possible on waterstones. Any properly formed edge will shave your forearm. The difference between an edge made at 600 grit vs. 8000 grit will mostly show itself in the quality of cuts in the most delicate foods (fish, herbs, fruits that brown, etc...).