Reestablishing Scandi Grind

[jackorion]

Hi all,

I have a Casstrom Woodsman which is a nice knife but, through error on my own part when I was more inexperienced, the grind it a bit off since resharpening.

I've tried resetting it using a combination of diamond stones and MDF/Sandpaper (my preferred sharpening method now) and, although it is sharp, it's still not got flat bevels. Is it a case of keeping going or should I just send it to someone to be re-profiled? Presumably some sort of belt grinder setup is the best way to just start it completely from scratch?

 

[Mesquite]

Hi all,

I have a Casstrom Woodsman which is a nice knife but, through error on my own part when I was more inexperienced, the grind it a bit off since resharpening.

I've tried resetting it using a combination of diamond stones and MDF/Sandpaper (my preferred sharpening method now) and, although it is sharp, it's still not got flat bevels. Is it a case of keeping going or should I just send it to someone to be re-profiled? Presumably some sort of belt grinder setup is the best way to just start it completely from scratch?

Try @Dave Budd , he loves sorting out scandi grinds.

Failing Dave, any of the knife makers on here ought to be able to help you out like Hillbill

 

[C_Claycomb]

What grit and type sand paper have you been using to reset the bevel? When I do stuff like that, I want at least 180 grit, 120 isn’t too coarse. Expect to use a whole sheet or two. Premium bonded aluminium oxide paper is better than silicon carbide wet and dry for this job. Silicon carbide this coarse tends to shed its grit rather quickly.

Problems can occur if the paper is not glued down. For dry sanding, a layer of 2inch wide masking tape on the board, then double sided tape between masking and sand paper works well. You want to be able to swap paper easily and cleanly while still having it stuck down.

Mesquite, you are bad! You know how Dave feels about Scandi grinds

 

[Dave Budd]

As intimated by my friends above, you might want to just use a knife with a proper geometry and give up on the scandi grind rubbish ;-) Proper knife for general cutting and a separate dedicated carving knife for whittling, even a cheap Mora carving knife.

Before St Mears made the 'scandi grind' nonsense popular, most actual Scandinavians would hollow grind their carving knives occasionally and then sharpen on stones until they became rounded, then back to the hollowing again. General purpose knives all had secondary bevels; then when the bevel got too obtuse they went back to the grindstone. Most homes had a grindstone of some type and if not then their neighbour did.

Unless you are extremely good at holding an accurate angle when sharpening, your best bet is to hollow grind it (even if it is roughly hollow using a bench grinder) and then when you use a stone you have two points of contact that essentially make a flat on the stone. You could have it reground to a flat scandi by a knife maker, but not me. I ONLY put single bevel grinds onto carving blades and they are hollow with a honed flat as described.

 

[Mesquite]

Mesquite, you are bad! You know how Dave feels about Scandi grinds

I said @Dave Budd sorts them out Chris, I didn't say he restores them

 

[jackorion]

As intimated by my friends above, you might want to just use a knife with a proper geometry and give up on the scandi grind rubbish ;-) Proper knife for general cutting and a separate dedicated carving knife for whittling, even a cheap Mora carving knife.

Before St Mears made the 'scandi grind' nonsense popular, most actual Scandinavians would hollow grind their carving knives occasionally and then sharpen on stones until they became rounded, then back to the hollowing again. General purpose knives all had secondary bevels; then when the bevel got too obtuse they went back to the grindstone. Most homes had a grindstone of some type and if not then their neighbour did.

Unless you are extremely good at holding an accurate angle when sharpening, your best bet is to hollow grind it (even if it is roughly hollow using a bench grinder) and then when you use a stone you have two points of contact that essentially make a flat on the stone. You could have it reground to a flat scandi by a knife maker, but not me. I ONLY put single bevel grinds onto carving blades and they are hollow with a honed flat as described.

Well as it happens part of the reason for wanting to reestablish the scandi is because I’d like to move it on - I have a mora 106 for spoon carving etc and don’t really use the woodsman as I find the blade is too chunky for ‘normal’ cutting use so I want to grab a fallkniven tk4 as I think that’ll be much more useful to me.

What grit and type sand paper have you been using to reset the bevel? When I do stuff like that, I want at least 180 grit, 120 isn’t too coarse. Expect to use a whole sheet or two. Premium bonded aluminium oxide paper is better than silicon carbide wet and dry for this job. Silicon carbide this coarse tends to shed its grit rather quickly.

Problems can occur if the paper is not glued down. For dry sanding, a layer of 2inch wide masking tape on the board, then double sided tape between masking and sand paper works well. You want to be able to swap paper easily and cleanly while still having it stuck down.

Mesquite, you are bad! You know how Dave feels about Scandi grinds

I was using a 400 grit I think so maybe I need something more aggressive…

Or I just sell it ‘as is’ - it’s not awful but it’s a little rounded

 

[TLM]

then when you use a stone you have two points of contact that essentially make a flat on the stone.

Excatly, a comment though, people whittle a lot sometimes use very slightly convex grounds because that gives more control.

Hollow ground blades and woodwork is often a bad combination. The few times sharpened actual scandi grind behaves a lot better but it does seem to sometimes depend on the phase of the moon.

 

[C_Claycomb]

I was using a 400 grit I think so maybe I need something more aggressive…
...

I would say that you always need something more aggressive than 400 grit. If you have chips to remove, bevels to reset, flat spots to take out, or a tip to reshape. 220 or 240 is the finest that gets the job done in anything like a reasonable time frame, but that can still be hours for some things.

It is quite common for folk to say they struggle to sharpen and it turns out they are using too fine a grit, often 1000, because that is what a bushcraft instructor said was a good sharpening stone. Sharpening, yes. Grinding, not so much.

You could try to sell as is, but this is a rare chance for you to learn some more sharpening skills, and skills is what all this bushcraft stuff is meant to be about (although gear often garners more admirers). Folk tend to like to buy stuff ready to go, so it might be a harder sell if it needs work.

Best of luck either way

Chris

 

[Murat_Cyp]

Excatly, a comment though, people whittle a lot sometimes use very slightly convex grounds because that gives more control.

Hollow ground blades and woodwork is often a bad combination. The few times sharpened actual scandi grind behaves a lot better but it does seem to sometimes depend on the phase of the moon.

I do not think he meant the traditional hollow ground in the sense that we see on hunting knives.

It is a hollow on a flat bevel. Very popular grind for wood working tools. I have such tools from top green wood tool makers including Nic Westerman and Kalthoff. They cut like zero scandi but much easier to sharpen and the contact surface much less compared to zero scandi.