Sharpening a new Mora

[Mora2013]

Hi. Complete newbie here.

I just bought my first "knife". It's a Mora HighQ Robust.

After using it for a few days, it's is sharp. But it is not "razor" sharp as I would like. The knife will be used mostly as a heavy duty utility knife - from breaking down cardboard boxes to whittling down wood to cutting rope/cables etc.

I've got a Norton combination India stone and a bunch of Nicholson files. I presume files are way too crude for a knife. Will the India stone work well for the knife? Or do I need to get an Arkansas stone ? I usually use the india stone for sharpening wood chisels, and gasket scrapers - not sure if it's fine enough to make a sharp edge on a knife.

 

[Magnaminous_G]

Real Arkansas stones are good, but water stones are the ultimate for scandi grinds.

 

[HeavyHanded]

The India stone will work well as far as an edge goes. You might want to strop it with a finer abrasive to finish it off for doing bushcrafting but could always try as is. If it works for your chisels and plane blades it might be good enough for your needs and you're already familiar with that stone.

As Mag says, a "softer" stone will work better, as far as aesthetics go the grind pattern will turn out smoother. This can be remedied somewhat by grinding the Mora to a true flat grind (they usually come with a slight convex and a bit of a hollow grind in the center - almost as if they grind them on a wheel and finish on a slack belt), or by slightly rocking the blade on the stone as you go.

 

[awestib]

Second M. + HH., also they come sometimes with a not so micro Microbevel which kind of defeats the purpose of a scandi grind. And again, for a nice finish on the bevel from worse to best I'd say diamond stones - (India?) - sandpaper (backed with a thick leather and a light touch works very well but poor feedback!) - crystolon - waterstones.

 

[Bugout Bill]

Second M. + HH., also they come sometimes with a not so micro Microbevel which kind of defeats the purpose of a scandi grind. And again, for a nice finish on the bevel from worse to best I'd say diamond stones - (India?) - sandpaper (backed with a thick leather and a light touch works very well but poor feedback!) - crystolon - waterstones.

India and Crystolon are going to be pretty similar.

 

[HeavyHanded]

India and Crystolon are going to be pretty similar.

Used with oil, the Crystalon will break down much like a waterstone - makes it a lot easier to get a nice scratch pattern on wide bevels, esp ones that usually have a slight convex - compared to the "harder" surface of an India stone (IMHO).

 

[Fred.Rowe]

I looked at this knife on line; is it a flat scandi grind or did they do something else? I see its .125 thickness. It didn't state what the grind angle is. Have you measured the angle? The older ones were ground at 25 degrees inclusive, but the grind lines were much higher. 60's / 70's
If you carry this knife daily and want to keep it sharp look at the ERU; it can be set to match the bevels perfectly, cradling the entire edge, so the factory grind can be maintained.

 

[filedog]

I recently got a Companion HD - very similar to yours, just different colors. Excellent knife BTW, can't believe how good the whole knife is,
and how ergonomic, and grippy the handle is. Mine came with a polished, but slightly hollow-ground, edge. Not very sharp though.
I started with a Dia sharp coarse, (with the grind layed flat on the stone) move to Dia sharp fine, then Spyderco med. Took a while, in the beginning
I was just hitting the high points, but it does result in a wickedly sharp edge. You can use whatever stone you have, don't see where it makes much
of a difference, as long as it's coarse enough to remove material at the right rate. ie, don't start with a fine stone, if your knife is like mine was, it
would take all day.

 

[filedog]

I looked at this knife on line; is it a flat scandi grind or did they do something else? I see its .125 thickness. It didn't state what the grind angle is. Have you measured the angle? The older ones were ground at 25 degrees inclusive, but the grind lines were much higher. 60's / 70's
If you carry this knife daily and want to keep it sharp look at the ERU; it can be set to match the bevels perfectly, cradling the entire edge, so the factory grind can be maintained.

They're scandi. I think the robust, or HD ones are 27. That's the beauty of the scandi knives, no need for a guide, just lay the whole edge on the stone, angle will never change.

 

[Fred.Rowe]

They're scandi. I think the robust, or HD ones are 27. That's the beauty of the scandi knives, no need for a guide, just lay the whole edge on the stone, angle will never change.

,

I like them as well. A very dependable grind. Have you found that the bevels will change over time when using a stone, or that type surface to sharpen? Uneven pressure is the nemesis of sharpeners. I carry a scandi around the homestead; the grind is a good choice for a wide range of applications.
When we were beating the idea around for the ERU sharpener; many of the conversations regarded its application in scandi sharpness; I think its the perfect solution because the bevel and abrasive angles match perfectly. I'll offer different abrasives next year, when we make another run; diamond or ceramic.

Fred.

 

[HeavyHanded]

In my experience, the grind on even a well-maintained Scandi will deviate a degree or so from shoulder to apex when sharpened freehand, and this is a good thing. It doesn't hamper their ability to work wood, and "toughens" the cutting edge up quite a bit. From the factory most are considerably more off than this, and some come with a deliberate microbevel, so not a big deal if they deviate more than a degree as long as it doesn't get into the high 20/low 30s inclusive. Keeping them perfectly flat from shoulder to apex causes them to loose some toughness for utility tasks and negatively effects the longevity of the edge for same. It can also entail a lot of stock removal to flatten them out in the first place.
By hand they are among the easiest to maintain in a general sense. Keeping them nice and relatively flat through the belly is the hardest part IMHO, but once understood is not very difficult.

 

[awestib]

For what it's worth - in my experience waterstones and the Crystolon stones make a much finer finish and a more even scratch pattern on a scandi bevel than diamonds for instance. There are some other methods to sharpen a scandi - sandpaper backed by hard leather gives a great surface for scandi sharpening, the only downside is rather poor feedback, often you see a hazy (not crisp) shoulder for instance which comes from not quite matching the bevel. Not every scandi knife is equally easy to sharpen. Provided that the actual scandi grind is well done, the contour of the blade, particularly the blade height (and also thickness) makes it much more difficult to keep the scandi bevel on the grinding/sharpening surface. A Mora is one of the easier knives due to light weight and narrow blade (less than 1 inch). Some custom scandis that have a wider blade (1.5 inch) are more difficult. You won't be able to keep the bevel on the medium just by placing you fingers on it, the weight of the spine will lift up the apex a bit and you have to counteract that with the handle holding hand. That however makes it more difficult once you approach the belly since you will have the tendency to overobtuse there unless you let go on the "twist" on the handle. The very tip area of a scandi has ultimately no surface anymore, so that may be a problem area as well.

In my experience the belly area often is slightly more acute and the sharpening/grinding does not quite reach the apex unless you account for that.

You could consider a longitudinal approach to scandi maintenance which works very well, keeps the bevel extremely flat and you can finalize it with a strop for a bit apex-convexivity.

Recently I changed my mind in regards to the "perfect" bushcraft style knife. I now clearly favor a thin (5/32 inch max), zero convex blade with no secondary bevel. Overall it is even easier to maintain and sharpen than a scandi and it performs at least as well for feathersticks, shavings etc. If you used HH washboard for instance, you can maintain the whole convex bevel while sharpening the very apex in one go and the feedback once you reach the apex is great. No concern of overobtusing over time.

Man, a lot of rambling here, sorry!

 

[HeavyHanded]

That barely qualifies as rambling, but for you perhaps...

I no longer have a favorite for bushcrafting, last couple camping trips I used my hatchet for everything but food prep. I do love the full convex on thin stock though - my Bark River Bravo Necker performs well for everything - one of my all time favorite EDU knives. My current fav is the Jarvenpaa puukko I used in the "new" WB videos. Is one of those Scandis you describe with a wider bevel. I've got that down to about 24 inclusive and it cuts everything well too, holds a useable edge for a loong time considering its carbon steel and goes in and out of a sheath all day.

Martin

 

[Fred.Rowe]

In my experience, the grind on even a well-maintained Scandi will deviate a degree or so from shoulder to apex when sharpened freehand, and this is a good thing. It doesn't hamper their ability to work wood, and "toughens" the cutting edge up quite a bit. From the factory most are considerably more off than this, and some come with a deliberate microbevel, so not a big deal if they deviate more than a degree as long as it doesn't get into the high 20/low 30s inclusive. Keeping them perfectly flat from shoulder to apex causes them to loose some toughness for utility tasks and negatively effects the longevity of the edge for same. It can also entail a lot of stock removal to flatten them out in the first place.
By hand they are among the easiest to maintain in a general sense. Keeping them nice and relatively flat through the belly is the hardest part IMHO, but once understood is not very difficult.

As the bevel angle becomes more obtuse over time, there's a change in the blades geometry and I believe this makes the blade technically stronger, but the angle change doesn't effect the toughness of the blade; toughness is a product of alloying. I figure thats what you meant.

Fred

For what it's worth - in my experience waterstones and the Crystolon stones make a much finer finish and a more even scratch pattern on a scandi bevel than diamonds for instance. There are some other methods to sharpen a scandi - sandpaper backed by hard leather gives a great surface for scandi sharpening, the only downside is rather poor feedback, often you see a hazy (not crisp) shoulder for instance which comes from not quite matching the bevel. Not every scandi knife is equally easy to sharpen. Provided that the actual scandi grind is well done, the contour of the blade, particularly the blade height (and also thickness) makes it much more difficult to keep the scandi bevel on the grinding/sharpening surface. A Mora is one of the easier knives due to light weight and narrow blade (less than 1 inch). Some custom scandis that have a wider blade (1.5 inch) are more difficult. You won't be able to keep the bevel on the medium just by placing you fingers on it, the weight of the spine will lift up the apex a bit and you have to counteract that with the handle holding hand. That however makes it more difficult once you approach the belly since you will have the tendency to overobtuse there unless you let go on the "twist" on the handle. The very tip area of a scandi has ultimately no surface anymore, so that may be a problem area as well.

In my experience the belly area often is slightly more acute and the sharpening/grinding does not quite reach the apex unless you account for that.

You could consider a longitudinal approach to scandi maintenance which works very well, keeps the bevel extremely flat and you can finalize it with a strop for a bit apex-convexivity.

Recently I changed my mind in regards to the "perfect" bushcraft style knife. I now clearly favor a thin (5/32 inch max), zero convex blade with no secondary bevel. Overall it is even easier to maintain and sharpen than a scandi and it performs at least as well for feathersticks, shavings etc. If you used HH washboard for instance, you can maintain the whole convex bevel while sharpening the very apex in one go and the feedback once you reach the apex is great. No concern of overobtusing over time.

Man, a lot of rambling here, sorry!

I like the thinner scandi ground blades also. With a thinner blade to start you, get the full benefit of this style of grind. No micro bevel needed here. Most factory blades, especially the less expensive ones have suspect grinds with grinding scratches and less that accurate bevels. If you get a good one they are truly an easy blade to maintain at a good level of sharpness.

 

[HeavyHanded]

As the bevel angle becomes more obtuse over time, there's a change in the blades geometry and I believe this makes the blade technically stronger, but the angle change doesn't effect the toughness of the blade; toughness is a product of alloying. I figure thats what you meant.

Fred

Very important to not let a Scandi become more obtuse over time. If it starts out at a degree or so deviation, and this doesn't open up as it gets reconditioned, all is good (generally requires a bit of work to make one this flat compared to the factory edge). I understand exactly what you're talking about, it is very easy to make a Scandi into an overly broad convex, seriously hurting its performance. As long as one consistently works from the shoulder it should stay pretty flat.

 

[Mora2013]

Thanks for all the replies!

Im getting myself a Japanese waterstone 1000/6000 grit to compliment my Norton India stone.

I noticed the "microbevel" after my original post. Looks like a wider angle than the main scandi grind on the blade.

Can I presume that as I sharpen this blade (Mora HighQ robust) over time - if Im following the main scandi grind, the "microbevel" will be removed, and the blade profile will become more like the main scandi grind thats on the blade?

Although one thing confuses me on this topic - I am presuming I should be following the scandi grind on the blade - but I read some posts above, and I wonder if Im supposed to follow the "microbevel"? That seems impossible to be consistent. Or if the "rocking" that someone suggested is what will sharpen the microbevel? Sorry for these newbie questions.

 

[Fred.Rowe]

If you like the 27 degree bevel and how it cuts, work the primary bevel. If you like the way it cuts with the micro bevel add it after you stone the primary bevels. Using micro bevels is usually a one two technique, with the primary first and the micro second. The 27 degree primary is a good all around grind for most work.
Micro bevels are mostly to add strength behind the edge and edge clean up after grinding the primaries.

 

[HeavyHanded]

Thanks for all the replies!

Im getting myself a Japanese waterstone 1000/6000 grit to compliment my Norton India stone.

I noticed the "microbevel" after my original post. Looks like a wider angle than the main scandi grind on the blade.

Can I presume that as I sharpen this blade (Mora HighQ robust) over time - if Im following the main scandi grind, the "microbevel" will be removed, and the blade profile will become more like the main scandi grind thats on the blade?

Although one thing confuses me on this topic - I am presuming I should be following the scandi grind on the blade - but I read some posts above, and I wonder if Im supposed to follow the "microbevel"? That seems impossible to be consistent. Or if the "rocking" that someone suggested is what will sharpen the microbevel? Sorry for these newbie questions.

I would highly recommend you follow the bevel angle at the shoulder, more or less. If you do so, you'll realize there is indeed a curve to your edge, and it is very difficult to make it completely flat. If you do make it essentially flat, you might wish to use a microbevel, but its a lot easier to maintain a Scandi with a very firm strop. For most people, the amount of freehand convex, spread across the bevel face on a Scandi, is more than enough to make the edge "tougher" from a terminal apex angle POV, even if that deviation is only a few degrees total. So, OK to slowly erase the microbevel, you'll likely be replacing it with a very, very shallow convex that will be tougher than the theoretical flat with microbevel, and still bushcraft extremely well. IMHO, a microbevel on a Scandi is only useful as a field expedient method of touching up the edge. Just as easy to apply compound to a smooth branch or piece of bark and strop on that.

 

[Mora2013]

Well, I put the Mora under the fine norton india, and then I used a new King 1000/6000 grit waterstone.

Not sure what to think.

Using the knife to slice advertisement paper, it seemed it was sharper after the India stone but not as sharp after the waterstone.

It does cut through cardboard easier and it does feather stick better when compare to new out of the box. But I didn't test these after the India stone, only after both the stones were done.


Overall it does seems sharper, but wish I had a more objective way to figure it out than test slicing paper and wood.

Also, it seems that some of the slurry is permanently on my 6000grit side of the water stone and I can't seem to get it out. Do you try harder to clean it or just leave it?

 

[HeavyHanded]

Well, I put the Mora under the fine norton india, and then I used a new King 1000/6000 grit waterstone.

Not sure what to think.

Using the knife to slice advertisement paper, it seemed it was sharper after the India stone but not as sharp after the waterstone.

It does cut through cardboard easier and it does feather stick better when compare to new out of the box. But I didn't test these after the India stone, only after both the stones were done.


Overall it does seems sharper, but wish I had a more objective way to figure it out than test slicing paper and wood.

Also, it seems that some of the slurry is permanently on my 6000grit side of the water stone and I can't seem to get it out. Do you try harder to clean it or just leave it?

Soak the stone for at least 15 minutes and rub with a fingertip - any embedded steel (grey streaks) should wipe off. Also, try some backhone passes on the 6000 to finish it off. I like to wet the stone and rub with a fingertip as I go - don;t want a bunch of swarf on the stone when working.

The 6000 edge should be a bit less "catchy" feeling than the India stone edge, but should shave/carve wood noticeably better. The 1000 King should also be fairly close to the fine side of the India in terms of edge qualities.