# How do you grind kitchen knife blades (stock removal) ?



## Matus

Hi,

as you may have noticed I started a thread with some questions about belt grinders. However I have realised that it would be very helpful to me to find out how do you guys grind your blades - in particular if you make your knives via stock removal method.

What I would like to ask is:
- how do you hold the blank?
- how do you setup your grinder?
- how do you get the profile you want (convex, wide bevel, etc)?
- how do you grind the distal taper?
- do you 'free hand grind' or do you use the tool-rest?
- do you use some jig to keep a give angle while grinding?


I am about to start stock removal on a little 1x30" grinder and would really appreciate you input so that I can avoid unnecessary mistakes.

Thanks in advance


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## Lawman

YouTube has some in depth videos on the subject
Try Walter sorrels or Gough customs. They have great vids


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## Matus

I have seen most of those videos (and they are indeed great), but none of the guys grind complex convex and/or wide bevels on kitchen knives - they do mostly full flat grinds on outdoor knives. OK, Walter has one video where he makes one chef's knife, but seems to put a more-less flat grind without elaborating on the details.


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## Mucho Bocho

Matus, You're asking for advise that takes years and thousands of knives to master. I've often thought about stock removal and making my own blades. Guess Marko's grinder got me excited. If I were starting from square one, I'd try to find a local school or local smith to teach you the ropes. A formal class would be ideal, you live in Germany, aren't you guys known for being the worlds best mechanical engineer, aerospace, automobiles... Got to be somebody associated with these place have experience with a grinder? Give them the ole puppy dog eyes and promise to be a good student. 

or

You could just go to Goodwill (not sure what they call it in Germany) and pick up a box full of old crap knives and just go to town. As long as you've got the proper safety wear, you'll be ok, and will learn, but very slowly. 

I'm sure you already have considered this, just saying...


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## jessf

Didn't Gandhi once say, "make knives, not excuses". I might be miss quoting the Mahatma. Just start!


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## Matus

Oh, I am not hesitating to start and to learn - it is very clear to me that there is no way around learning-by-doing here. I plan to use some cheaper steel I have, cut it to some rudimentary blade blanks and grind away until I can get some consistency. I am just hoping for a few tips & tricks as at the end - I want to be able to grind a bevel that works well - what means getting different angles at different positions (distance from the edge) and I could use some advice there.

I did briefly check out the possibility to take a class (and will look into that more seriously), but most what I found concentrates on forging (kinda get one forged blade in a course of one weekend - that does not sound to me much like learning the technique, but just satisfy the one-in-a-time curiosity). I would be interested in classes, but would first have to find a knife maker whose work I like AND who is actually interested in giving such a class.


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## RDalman

If you find yourself going on elk safari up north you know where to find me 

I'll say though that I believe in finding your own way, what works for you..

I free hand, and recently I've thought it's actually alot like working on stones, you put pressure where you want to remove steel, and find the motion needed to get to that spot without messing up another, or get to much heat.


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## Matus

Thanks Robin. That is the kind of advice I am looking for. Should I find the excuse to come up north again (we have been to Norway last year and only crossed south Sweden) than I will give you a call


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## Dave Martell

Hi Matus,
To keep it simple try to think of the side of the blade in two large sections, there's the flat section that goes mid-height to spine and then there's the bevel which goes from mid-height down to the edge. These two sections are mostly ground independently with most time being spent on the bevel. Once you have the bevel ground and some taper ground into the upper flat/spine section you can either leave the transition line as is or blend it all together to form a more convex shape. 

And before all that, make the profile of the blade perfect - this is VERY important to remember. You'll be kicking yourself in the ass if you work on the profile after grinding the sides of the blade.

That's the most basic of it.

Dave


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## Dave Martell

You might want to scribe a center line in the edge to ensure even grinding along the length. This can be very helpful when starting out. 

Also, stop and look as you go, inspect from all angles to make sure you're grinding even and no curves/warps or other weird things are happening.


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## Matus

Thank you Dave for your advice. That is very good point about the doing the profile first.


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## Matus

So, I have just received 11 pieces of 1.2442 in 3.3 x 60 x 660 mm, 2 pieces of 2.7 x 40 x 650 mm and 2 in 125SC 2.7 x 50 x 735 mm. 

On top of that I have incoming O1 (1.2510) - 2 pieces in 2,2 x 40 x 1030mm and 2 in 3,2 x 60 x 103 0mm AND 1.2519 (O1 with more C and a lot more W) in 2,2 x 50 x 1000 mm.

That makes it all together nearly 15m of steel - I should be set for a while  The 1.2442 is the last stock available in this size (from Achim in DE) - there is little more in smaller width available. I plan to use the one I bought for gyutos once I get some grinding experience. The O1 is form China (as I learned afterwards) and will be in the first place used to learn grinding.

I am very curios about the 125SC (further development of SC145) - with little less C and little more Mn (to improve HT properties) - should be similar to white#2 but even more pure (!). I am really curios about it. The nice thing is - there is plenty of this steel for years to come and it can be had in thickness suitable for stock removal kitchen knife making.

All the above probably sounds a little crazy, but I am really motivated and not I have all the basic tools (little grinder, angle grinder, etc.) to get the ball rolling. I am really curios how long it will take me to get the basic grip on the grinding (so that the result resembles a knife).

My current plan - make a batch of 150 or 180 mm WA petty blanks from the O1 steel and use them to learn the basic grinding. I will use our Yoshikane SLD 150 as a template for the profile and for the bevel geometry.


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## gic

I'm also interested in learning about stock removal. What's the best steel to start with and where is a good place to buy it?


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## Matus

gic, the steel choice will in my (very limited) experience depend on whether you plan to heat treat your own blades (but probably do not have a proper HT kiln yet I suppose). If yes, than steels like 1075, 1084 or O1 are often recommended since these can be HT without strict temperature control. If you will outsource the HT (I do), than it will depend on what steels can given shop or company heat treat. 

Even if you outsource your HT and are not really limited by the steel choice, I would still go with a simpler, low alloy carbon steel, since it will be somewhat easier to cut and grind than some other steels. For comparison - I found 80CrV2 or O1 easier to grind and cut as for example D2. This is in particular relevant if you plan to grind the blades with a file (or manual filing jig) and not with a belt grinder. Also - it does not make much sense to start with some expensive steel.

What may help is to to buy precision ground steel (in particular for kitchen knives) - this will eliminate the need to straighten the stock steel (which is normally cut to size from large sheets and gets slightly distorted in the process). This costs extra, but makes your life much easier - in particular if you do not have a dedicated tools to make the steel as flat as possible before you start cutting the blank out.

Check out youtube videos from guys like Nick Wheeler, Walter Sorrells, Caleb White Knives and others. None of these guys specialise in kitchen knives, but they have excellent videos on general stuff (tools, how to make basic knives, handles, mistakes to avoid, etc.) which I found (and still find) very helpful.


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## Matus

Just got my first hands-on experience. I was working on the 240mm D2 gyuto that I ground initially with a file (a jig). To get the final shape I have used the techinique I 'discovered' (for myself so to say) when I cross-draw a file along the blade with both hands, I would hold the file under slight angle and thus use just the edge of the file. While this proved to be a very fast technique, it leaves VERY deep scratches. I only realised how deep these are once I have tried to remove them with 60 grid sandpaper. To cut the time down (which would have been hours even though the knife was no HT-ed yet) I moved to the grinder with the A100 gator belt (whether that was the right choice is something I do not know, but I did not want to use some coarse grit belt that would cut too fast) and started to remove the file marks. It turned out, that to get them all out (I am not quite there yet) I had to remove so much material, that the knife lost about 3mm of the blade height (before I started I had the edge thickness of some 0.3mm which I wanted to keep for the HT).

So - I did not loose the knife yet, but it is a lesson learned. Should I ever be using this particular filing technique than I will have to stop some 0.3 - 0.5mm (thickness wise) from the intended blade thickness and move to 'normal' filing and sanding. I will see ho much of the blade will be left once I will be done with the scratch removal (I do not want to leave that to after HT) - I may need to shorten the knife to 210 mm to keep some reasonable proportions.

I have more bevel ginding ahead - the 8 blanks for 180mm petty knives were cut with a angle grinder yesterday and now wait to be grind to final profile and then beveled.


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## RDalman

Haha it's not going to be long now before you go buy a 2x72.

Looking forward to see some pictures.


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## Matus

RDalman said:


> Haha it's not going to be long now before you go buy a 2x72.
> 
> Looking forward to see some pictures.



Indeed  I already have one on radar already, but du not want to push for it too soon - I can learn a whole lot before getting a better (and more expensive) tool. I first need to prove (to myself at least) that I can make a knife that is worth using. I am not quite there yet 

I do take photos, if not for anything else then to entertain those more experienced makers  It must be load of fun watching beginners to roll blindly towards inevitable mistakes


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## jessf

Photos photos photos potatoes


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## Matus

jessf said:


> Photos photos photos potatoes



Let me do something about that tonight


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## Matus

I would have one question - how do you guys hold the blade while grinding the bevels? Obviously one hand is holding the tang, but I am having hard time to figure out how do hold the blade to make sure that I keep the angle and constant pressure while moving along the belt - AND not grinding my fingers 

And second question - do you grind on the platen in vertical or near horizontal position?

thanks


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## RDalman

I like to think it's similar to working on a stone. The hand not holding tang is doing most of the control work, if that makes sense. In reality they probably help eachother. I use all the grips, and most imaginable positions, whatever works to get desired effect. I've never cared for angles much, I think of it more to remove steel wherever needed to get the blade I want. Usually it's about getting the right contact point/applying some pressure in the same sense you would when working on a stone. This may not relate at all to your tools and process though, since I'm grinding hardened steel which tends to "skate" the belt and not grab like soft steel does.


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## WingKKF

You know those Japanese knifemaker grinding videos where they use a plank with metal brackets, pins(?) and a tightening wedge on them to hold the knife when they are grinding on a waterwheel? Maybe you can make something like that too.

[video=youtube;iCtx8VYxUK4]https://www.youtube.com/watch?v=iCtx8VYxUK4[/video]

I think Dave Martell had modified his Harbor Freight 1X30 for horizontal operation. I'm assuming that's the preferred orientation when working with knives.


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## Matus

Thanks. That helps and timing is spot on - I have 8 180mm petty blanks ready for bevel grinding.

That video is really nice - masters tend to make what they do look so easy.


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## Eric

Hi: Good luck in you new endeavor. I took a class with Dave Lisch here in Seattle. He provided j shaped pieces of plastic, I think cut from a plastic cutting board, which we used to exert even pressure on the blade as we pulled it across the belt. We used a flat platen and a tool rest. You could use anything I think, such as a block of wood. This technique really helps in exerting even pressure and maintaining a constant angle as you pull the blade across the belt. It also keeps your fingers from burning, but you need to be aware of blade temp. Hope this helps.


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## ant_topps

This is a fairly decent and in-depth video on how to grind a chef knife.

Part 1
[video=youtube;hXeiFVSYdhc]https://www.youtube.com/watch?v=hXeiFVSYdhc[/video]

Part2
[video=youtube;XiVuuCMX0RA]https://www.youtube.com/watch?v=XiVuuCMX0RA[/video]


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## Matus

Thanks. I came across the first of the two videos recently and need to look at it more closely. But I would appreciate input from those more experienced on the technique showed in the videos.


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## RDalman

Matus said:


> Thanks. I came across the first of the two videos recently and need to look at it more closely. But I would appreciate input from those more experienced on the technique showed in the videos.



I didn't watch all of it, but some thoughts. He scribes his slightly bent blank pushed down to be straight, so his scribed lines will flex back out of true as soon as he lets go of the pressure. His "finished" blade looks unsharpened and thick at the edge to me. It probably makes a good enough blade, but one can go at it from different perspectives. You set your own standards for what you want your knives to be, and then find a way that works for you, how to make it.

My tips for you knowing some of how you've previously done; Keep the atoma plate handy to check your progress, hog off steel with whatever tool and technique works best for you. Don't be afraid to mess up, but keep fixing your mistakes.


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## Matus

Thanks Robin. One thing that most (if not all) who actually make knives worth buying say the same thing - keep improving your work all the time. I completely agree. But at the very beginning there is also a danger of trying to 'polish a turd' (that is a quote). I.e. trying to get something much better than one at given stage is able to.

I have just started with the learning - my first 180mm petty blank is nearly finished - I am deciding on how thin (I mean further up from the edge, I will keep the edge at around 0.3 mm thick) should I grind the blade prior to HT. On one hand it will be harder to grind after HT, on the other hand I expect the hardened blank to have better 'feedback'. But that is why I prepared 8 of these - so that I can try things out and learn. It is so much fun


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## Dave Martell

It's great to see the knife making bug getting to so many people. I enjoy these threads a lot.


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## Matus

Dave, it is the support and advice that you, experienced knife makers, share with us that makes it possible for us to to learn much faster. Big 'thanks' from my side for that.


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## Dave Martell

Matus said:


> Dave, it is the support and advice that you, experienced knife makers, share with us that makes it possible for us to to learn much faster. Big 'thanks' from my side for that.




Hey how do you think I learned 1/2 of what I know?


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## Matus

Dave Martell said:


> Hey how do you think I learned 1/2 of what I know?



In a knifemaking college?


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## Matus

A few more blades ground down the road and the first that was also ground (smaller adjustments to the grind) after HT. It is a D2 gyuto. I am having a lot of trouble removing scratches on a belt grinder (the 1x30"). I have ground the blade with Sait 7S grit 40 belt, did the work I needed to be done. Then I have moved to 80, 120 and 240 belts (all Sait 7S) trying to remove scratches form the previous belt (not easy to observe as all are going in the same direction). I was not happy already during the grinding as I was often getting the impression that I can not 'reach' certain places on the blade - like I would have low spots roughly in the middle between edge and spine. Once I have moved to hand sanding I had to go down to 80 grit paper and still needed 1/2 hour to remove scratches left by the grinding.

I am wondering what was the reason. On one hand - the 'platen' the grinder has is some 3mm thick L-shaped piece of metal that is only attached to the grinder on one end, so it can give under pressure. On the other hand I am having hard tome to estimate when I have removed the scratches from the previous step as I can not really grind under different angle with every step as that just seems hard to do on a belt grinder + there is not enough place on this little one.

I would appreciate your thoughts.

This is the grinder in question - here you can see the 'platen'. I remove the 'work rest' for bevel grinding though:


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## gic

Well for what it is worth, when I took a lesson with WillC he often used a push stick to apply pressure to the part of the bevel that he wanted to grind more of...


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## Chuck

Matus said:


> A few more blades ground down the road and the first that was also ground (smaller adjustments to the grind) after HT. It is a D2 gyuto. I am having a lot of trouble removing scratches on a belt grinder (the 1x30"). I have ground the blade with Sait 7S grit 40 belt, did the work I needed to be done. Then I have moved to 80, 120 and 240 belts (all Sait 7S) trying to remove scratches form the previous belt (not easy to observe as all are going in the same direction). I was not happy already during the grinding as I was often getting the impression that I can not 'reach' certain places on the blade - like I would have low spots roughly in the middle between edge and spine. Once I have moved to hand sanding I had to go down to 80 grit paper and still needed 1/2 hour to remove scratches left by the grinding.
> 
> I am wondering what was the reason. On one hand - the 'platen' the grinder has is some 3mm thick L-shaped piece of metal that is only attached to the grinder on one end, so it can give under pressure. On the other hand I am having hard tome to estimate when I have removed the scratches from the previous step as I can not really grind under different angle with every step as that just seems hard to do on a belt grinder + there is not enough place on this little one.
> 
> I would appreciate your thoughts.
> 
> This is the grinder in question - here you can see the 'platen'. I remove the 'work rest' for bevel grinding though:



There are several factors that are working against you with your a 1x30. Since you only have a 1" wide platen, you have a greater chance of introducing the blade onto the platen at an angle and not perfectly flat to the platen. This creates deeper scratches as the blade is going across the edge of the platen. I'm not sure how stable your platen is, or if it has a ceramic glass backing, but lack of stability can cause problems as well. Another big disadvantage you have with the 1x30 is no ability to vary the speed of the belt. Fast is great for removing lots of metal, but a slower speed gives you much more control when working out scratches.

Something I do to find those deep scratches before going to the next belt, is to take the blade to my vise, using a sanding block and the same grit paper as the last belt I used, I sand the blade length ways (opposite of the belt marks). It won't take long doing this for the high and low spots as well as the deep scratches to show up.

I'm pretty sure a variable speed 2x72 machine and lots of grinding practice would be the cure to your problems.

Hope this helps!


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## Matus

Thank you. Those are all good points. I did have one intermittent loop when after 80 (or 120) belt I went to hand sandig with 80 grit paper and since I was not seeing progress after a while - I went back to the belt sander and even with 40 grit belt I had a really hard time to get those 80 grit scratches from hand sending removed from some parts of the blade.

Yes, the platen is rather flimsy and probably in the core of the problem.

2x72" grinder is in serious planning phase - if everything goes as hoped, I could have one by the end of the year.


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## Kippington

Oh man I didn't realize until I watched those videos just how different stock removal is from grinding a forged blade.

There's no way to scribe the center of a forged blank, its way too irregular, so instead of starting at the edge I have to start from the spine and grind my way to the edge from there.
Deep hammer marks are the biggest pain in the ass for me to deal with at the grinding stage and I quickly learned to hit accurately while forging. It only takes one bad swing with the hammer on a hot blade and the corner of the hammer leaves a big ol' imprint on the blade surface that adds another half-hour of grinding to the project.

I can't imagine how long it would take to grind hardened steel like some of you guys do. I use a weak/cheap 1x30 belt so perhaps it's easier with a proper bladesmith grinder. I have to anneal my blanks after forging to keep the metal soft enough for my grinder, which comes with the added benefit of being able to bend a crooked edge straight. This kind of makes up for the lack of center marking that you would do on a stock removal edge.

Interesting thread!






Checking a 40 grit finish for irregularities. Next I'm gonna cut out the choil then prepare for a clay-coat marquench.


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## Matus

Indeed - I find grinding blanks made out of stock steel demanding enough. Grinding bevels on dorged blade is entirely different level. Since you are also using a small 1x30" grinder I would appreciate any tips or trickes how to get most out of it.

I agree that grinding the blanks from stock after HT would take forever with this little weak grinder.

On the topic of scratches on the D2 knife I am working on at the moment. Obviously large part of the 'problem' is the steel itselt. It is VERY wear resistent. I have already spent nearly 3 hours going from 80 to 400 grit and I am not finished yet. The work with the 80 was so tough, that I went with sanding parallel to the knife axis just to be able to put more pressure into it without risking damaging the edge. I am NOT lookimg forward to the other side. 

I have a batch of O1 knives in process (still grinding prior to HT). I will not be going back to D2 anytime soom (at least not for large kitchen knives). I do plan to try stainless, but it will be AEB-L and Niolox. I will probably stay with O1 as my main carbon steel for the foreseeable future.


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## Kippington

How to get the most out of a 1x30"? Seeing it's not as fast or powerful as some of the other grinders out there, use the coarsest grit you can find and expect it to take a longer time. It's not a bad thing for a beginner!
The process is slowed down enough that I can grab a beer, wear my earphones under my hearing protection and chill out to music while taking my sweet time at the grinder trying to get things right. Its not like I'm making a product for a waiting customer; I can stop and resume whenever I want.
Use time to your advantage and get everything right. The blade above took maybe 5 hours over 2 days to get to that state from forged blank. It still needs a few hours work, but I have to heat treat it before it gets too thin (edge is 2mm).

Polish a blade from scratch once and you'll never forget the simple rule - Each polishing stage depends on the last, all the way up from the rough shaping.
What tools are you using to do the hand sanding? Maybe your flat backing behind the sandpaper is bending as you put pressure on both ends, leaving an arch above the middle of the blade.

If you think you have a low spot you can check with a flat object and a back-light. It's a very quick test you can also do while coarse grinding.






A slightly convex blade face is the easiest one to polish (and makes for a good kitchen knife!).
Chuck also had some good advice about the scratches.


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## Matus

All good points. I agree that trying to hurry is a recipe for a poor result. Most of knives I grind do indeed have a convex grind (flat grind on a tall kitchen knife would not make for too impressive performance anyhow). Yes - the support I use for hand sanding is a piece of simple hard wood with a cross section of 10x30mm, so it most probably bends a little. But I do not really have problem with hand sanding (it just takes very long in the case of the D2 steel), but when sanding with the grinder where the semi-stiff platen is probably not an advantage.

I really like your 'checking screen' - reflecting a pattern onto the blade is indeed a great idea to see local disturbances to the surface. I will try to make something similar. I am using similar technique to check for the shape of the grind as you show above. It also allows to spot some left-right asymmetries.


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## thorax

In a general sense, I use a work rest tilted to the bevel angle and hold in a fixture, on a flat platen, post heat treated. I am currently working on a 8" Gyuto that will require a large work rest. 
I do not yet have the skills to grind a knife of that length freehand. I find with this method, I have very little scrap.


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