Sharpening a Scandi

[CPShines]

Hi all.

I've read several threads on sharpening here and on the BCUK forums, and I'm still after some personal advice.

As a result of all that information-sifting, I have bought one set of crocksticks, set at 20 and 25 degrees with fine and medium ceramic rods, a 20x magnifying handlens, and a slightly dubious combination stone that I'm not too confident about.

I have just received my first Scandi, a Helle Nying (see here (http://www.jls-wednesbury.com/default.asp/pages/p.5990/ecombuilder.html)). The blade is triple laminate stainless steel with what looks to me like a typical scandi grind. It's sharp but not monster sharp, and I'm wary of running it down the crock sticks and ruining it. I've thought about practicing on an old Kershaw lock knife that I've not used for years, but the grind on it is very different so I'm not sure what that'll tell me about sharpening the scandi.

Does anyone have any experience on sharpening this kind of blade that they would share with me before I go ahead and try it out? I was wondering if I should try stropping it first before going at it full on with the ceramics.

Any tips welcome.

bp1974

[Sajuma]

I would put the blade flat against stone and move the blade like you try to whittle the stone. (note! the bevel touches stone all the way.)
After a while, you get the burr on opposite side of the blade and then you turn and do the same for other side. I dont know how course your stone is so work from course stone to fine. Then I would strop it.
Easy way to do this is to take an old leather belt, cut 30 -40 cm piece and glue this on piece of flat wood. Then put some buffing compound on the belt and move your blade against it.The angle is the same when sharpenin your blade. If you dont have buffing compound you can use polishing paste that is used for polishing cars valves.

If you still have problems, PM me and I try to help if I can.

And by the way, Welcome to this Funnyfarm, have fun!

Juha

[Basemetal]

Welcome to British blades bp1974 :cool20:
One of the key design features of the scandinavian grind is that it is easy to sharpen. The broad flat primary grind gives you plenty of stability to index onto a flat stone -the blade is almost its own honing guide. The important thing is to remove material from the whole of the grind (ie the whole bevel in a scandi grind) as you sharpen. The laminate helps this as most of the material you remove will be the softer outer steel.
Resist the temptation to add a steeper angle at the cutting edge -just keep the whole grind flat and you'll see how the scandi grind "works". The conventional "try to cut slices off the sharpening stone" approach works well. Here's another link where the merits of the scandi geind are discussed...

Sharpening Scandi Grind Blades (http://ragweedforge.com/scanshrp.html)

The crock sticks will not be particularly suitable for a scandi if they are round-the angles are unlikely to match it and you really want to have a flat stone.

A guided system like Lansky. Gatco, Edgepro can be used -but you need to set the angle to match the existing grind (Or be prepared to change the existing grind). But a flat conventional stone is as good as anything.

Danny

[Kevin]

Dan.....When sharpening a scandinavian type flat grind on a flat stone laying it flat on the bevel...how do you sharpen around the belly of the blade and towards the point, as this is rarely the same flatness /angle as the straight edge and is not as easy to maintain........any tips?

[CPShines]

Dan.....When sharpening a scandinavian type flat grind on a flat stone laying it flat on the bevel...how do you sharpen around the belly of the blade and towards the point, as this is rarely the same flatness /angle as the straight edge and is not as easy to maintain........any tips?I was wondering this too. The consensus seems to be that a flat stone is best for a scandi grind, and I know when sharpening other blades in the past that the hardest bit to get right is the curve towards the point.

Many thanks for all the advice offered so far, and thanks for that link, Danny. I had a hunch that crock sticks might not be ideal for a scandi because they're round - it's good to have that confirmed by people who know what they're talking about.

So, now I'm going to go with a fine flat diamond stone and a strop. Any comments on getting the curved part of the edge just right would be greatly appreciated.

[CPShines]

Looking at Axminster's website, the Spyderco ultrafine ceramic benchstone looks like a good place to start. Do they stay flat for longer than other stones?

[Hoodoo]

If the knife is brand new, I'd try the strop first. That might be all that is needed.

As for the curved part, one solution is to sharpen your blade in short sections, always drawing your blade across the stone in a direction that is perpidicular to the tangent of the edge. Just keep the bevel as flat as you can on the stone and try to feel the bevel.

[Basemetal]

I can't really add to Hoodoo's advice above. If the original profile looks right I try to maintain it and let the blade guide itself on a flat stone. The curve is always a difficullty -but like sharpening a curved chisel or a gouge it seems to work well enough with care and light strokes.

One trick you can use if you have a Lansky /Gatco is to set the stone up for the grind angle precisely (by adjusting the attachment of the stones to the guide rod after picking the nrearest guide hole) and then set the knife blade in the clamp so the curved edge presents a uniform radius to the pivot. If you do this you'll get a mathematically flat grind over the swept radius. Pedants amongst us (I know who you are!) will have realised that Lansky/Gatco systems normally give variations in grind angle with distance from pivot and that this has to be taken into account on long blades. For once, when sharpening radius curves, it sort of works in your favour.

Danny

[Dave Barker]

helle actually make a sharpener for their blades too.

I think it is only available in Norway though and it costa about 20 quid.

It comprises of a small handle that has a 2 tunststen blades inside it. These are charges positive and negatively.

Designed for the helle blades the angles is fixed to that found on the blades, fix the blade / knive edge up in a vice, then run the sharpener across.

A few light strokes is enough.

I always finish with a run through the gerber pocket sharpener of a quick strop on a dry belt.

It also works well on the hand forged blades too!

If you are interested then let me know and i'll send one to you...

[CPShines]

Thanks for all the advice. I'm going to try stropping first and get a ceramic stone for future use. Dave, thanks for the offer and the information, that's very kind of you. I'm going to use a ceramic stone for now so that I learn how to sharpen all blades, rather than getting anything that's specific to the Helle brand.

This thread's helped get things clear in my mind. Thanks again.

bp1974

[TLM]

A fully flat sharpening is quite OK when cutting is the primary work. If wood whittling is to be done I prefer a very slightly convex sharpening, that gives you better control.

TLM

[MotorbikeMan]

Thanks for all the advice. I'm going to try stropping first and get a ceramic stone for future use. Dave, thanks for the offer and the information, that's very kind of you. I'm going to use a ceramic stone for now so that I learn how to sharpen all blades, rather than getting anything that's specific to the Helle brand.

This thread's helped get things clear in my mind. Thanks again.

bp1974
My own personal view is that ceramic stones are the way to go, but that could just be 'cos I'm a lazy git :D No haveing to soak them in water, just clean then with a green scourer every now and then. Only thing to watch is that you don't drop them onto a hard surface. I have a Fallkniven DC4 as part of my pocket edc. Diamond on one side if something gets a chip or really dull and ceramic on the other for that final edge.

[Sajuma]

A fully flat sharpening is quite OK when cutting is the primary work. If wood whittling is to be done I prefer a very slightly convex sharpening, that gives you better control.

TLM

Me too but that's because were Finns...Finnish blades normally dont have fully flat bevels but a secondary "micro bevel". Have a good Midsummer or should I say: Hyvaa Juhannusta!!

Juha

[CPShines]

I didn't know that about Finnish blades. I think I'm going to keep this Helle with the traditional flat grind - I like the idea of keeping it as it was designed to be. And I'll try out a convex grind or a small secondary bevel on a different knife.

Thanks for the cleaning tip, Jon, that'll be useful.

[CPShines]

Well, I bought a very nice hard-backed strop from HandAmerican (http://www.HandAmerican.com) . First thing to say is that they provided excellent service and I will definitely use them again.

Bearing in mind I've never stropped before, I gave it a go last night and my knife now takes the hairs off my arm.

I found it difficult getting the stropping angle and motion right and my blade now has a few thin scratches on it so I guess more practice is needed. I didn't use any paste last night, I used a leather that's been treated. I might give it a go with the chromium oxide and see how that shapes up.

Any tips on stropping would be most welcome. The way I did it was to place the blade on the strop so that the bevel was flat on the leather and then drag it towards me, flip it over and do it the other way. Like I said, this worked but the blade has suffered a bit and the strop has some worn patches on it now. Is this normal? Or is it only normal for a hamfisted first attempt?

[Basemetal]

First up...this is a single bevel scandi you're stropping? (Which knife?-just nosey:))

You've achieved a sharp edge :cool20: But the scratching surprises me -I would have expected polishing. The fact that you have some wear does mean metal is being removed so it sounds like the leather treatment has rendered it fairly agressive. I would normally strop each side fairly lightly 10-20 times then turn the blade over and do the other side, always dragging the blade away from its edge. You have the leather on a flat hard surface?
Using stropping compound makes the metal removal more efficient (and possible more even) but don't underestimate stropping...
The strop should leave the bevel near mirror polished where it has been in contact. Normally it works very quickly.
You should be able to polish out the scratches on the strop itself, but have a good look for what caused them -embedded swarf or grit -because it just shouldn't happen...

Danny.

[CPShines]

It's a Helle Nying - short blade, triple laminate stainless steel with a single flat grind (see here (http://www.jls-wednesbury.com/default.asp/pages/p.5990/ecombuilder.html)). I was surprised by the scratches too. Part of the problem may be that I was doing a stroke on one side, then turning it over and doing the other, rather than doing 10 or so on one side at a time, so in getting the angle wrong every now and then I'd be wiping the flat of the blade over the strop rather than the bevel.

The strop is a hard-backed hone like this (http://www.handamerican.com/flatbed.html). It's very nice and I don't think there was anything on the leather that might cause the scratching. I'll look at it closely again tonight. The only thing I can think of is that in my first attempts I roughed up the leather a bit in some areas, and maybe this caused a problem. It's also possible that the scratches came from using the knife on a piece of hazel last weekend and I simply didn't notice until after stropping.

[MotorbikeMan]

It's a Helle Nying - short blade, triple laminate stainless steel with a single flat grind (see here (http://www.jls-wednesbury.com/default.asp/pages/p.5990/ecombuilder.html)). I was surprised by the scratches too. Part of the problem may be that I was doing a stroke on one side, then turning it over and doing the other, rather than doing 10 or so on one side at a time, so in getting the angle wrong every now and then I'd be wiping the flat of the blade over the strop rather than the bevel.

The strop is a hard-backed hone like this (http://www.handamerican.com/flatbed.html). It's very nice and I don't think there was anything on the leather that might cause the scratching. I'll look at it closely again tonight. The only thing I can think of is that in my first attempts I roughed up the leather a bit in some areas, and maybe this caused a problem. It's also possible that the scratches came from using the knife on a piece of hazel last weekend and I simply didn't notice until after stropping.
That would be my logical choice. Whenever I've stropped, even with a rough bit of leather, it leaves a highly polished edge

[CPShines]

Yes, you're probably right. I'll keep working on that mriror finish.