primitive blade edges

[ChrisCraft]

recently, ive been trying to get back to our oldskool roots more and more, and integrating some classic, tried and tested stuff into my mind & kit.

i came across a slight dilemma when i tried to sharpen a scandi edge knife with a stone that i found by the river. i came to the conclusion that unless you have a straight, as well as flat stone, its not really going to work, and will change the edge to a convex hybrid. those kind of stones are not so easy to find, and will probably have to be made, using harder stones, to re-shape them.

has anyone some knowledge on primitive edges of blades ?

was a convex edge used on most things over here ?

how old is the scandi design ? ... how long has it been on english soil ?

[MongooseDownUnder]

Personally I would not imagine that blades would have been defined by the edge as they are now. I envisage a sharp blade being the most important consideration.

[FishyFolk]

To polish up an edge my grandfather used a sharpening stone that was so old it was completly rounded off. His jnives where all so called scandi-edge. He had the knife in one hand and the stone in the other, and used it more or less like a chef would use a knife steel. It does not have to be perfect, it just have to be sharp enough to do a good job...

[ChrisCraft]

mongoose - i think your right, people didnt over-think, and analyse so much back in the day, they just got the job done. so ' very sharp ' woulda been good enough :)

fishy - im happy with how it came out, it was sharp enough to do what i wanted.

i was just curious, as almost all stones i found were shaped more-so for a convex edge.

im gonna try again sometime, with my axe, as those river stones seem perfect for that.

[MongooseDownUnder]

On a side note I have sharpened a knife on a concrete curb, it wasn't flash but it was sharp (probably a bit serrated too) and got the job done. Could you crack a river stone in half and then rub it on a large rock to level it off?

[ChrisCraft]

yeah, could do that. might take hours, but once its done, its a piece of kit in your pack, that will last a good while.

ill have a play with whatever i find. i wont spend hours, but ill see what happens.

[SteveW]

I can just remember, my grandparents sharpening knives on the back door step of the house. It was slate and they got a fine edge with a bit of spit as lubrication.

[saxonaxe]

When I was a 16 year old Deck Boy I learned from the older AB's who sharpened their knives on the steel wire standing rigging aboard ship. Many carried a 'Green River' knife with carbon steel blade and they would just sweep it down the steel wire a few times each side. Once the Bosun decided I could be trusted to use a knife without losing fingers I used the same method on my Green River for years.

http://i279.photobucket.com/albums/kk136/highandry_photos/95d9383f-ba97-44ae-9506-a595a66216af_zpsf9fe4c23.jpg

[Whistle]

I can just remember, my grandparents sharpening knives on the back door step of the house. It was slate and they got a fine edge with a bit of spit as lubrication.

Back in the dark ages when we used to hand sharpen our microtome blades we used to have slate beds

to which we added oil for lubrication and different grades of medium , fine

and very fine carborundum powders ...

The carborundum powders would provide more "bite" than the relatively soft slate alone ...

different grades were used depending how badly your blade needed sharpening from just renewing an edge

to grinding out a nick or worse damage ...

The blades were then " finished " on a leather strop with a coarse side of rough waxed canvas

and a fine side of chromed leather treated with jewelers rouge ...

but very heavy damage meant the blade had to be sent away to be re-profiled ...

Cheers Whistle

[Whistle]

On a side note I have sharpened a knife on a concrete curb, it wasn't flash but it was sharp (probably a bit serrated too) and got the job done. Could you crack a river stone in half and then rub it on a large rock to level it off?

Yeah ... a lot of sand stone types , being sedimentary in origin , have natural "cleavage planes"

and often split along the layers quite easily ... many of the sandstones in the Orkney Isles can be split

and examples can be seen in Neolithic dwellings and turn of the 18th / 19th century "roofing tiles"

Best bet would be to look for some sandstone with obvious banding or layers ... should cleave easily then !!!

Cheers Whistle

[ChrisCraft]

sharpened an opinel on a brick earlier today, just cos it was the closest thing to hand.

i only spent 2 mins on it, so it wasnt perfect, but it came out sharper than it started off as.

[OakAshandThorn]

I've used quartzite stones found in and near brooks that are flat enough to hone a Scandinavian grind without convexing it. You don't find them everywhere, but such stones do exist ;). That said, I'm not sure what grind predates the other, but I do know that stone tools that are ground into shape most often have a convexed edge.

[ChrisCraft]

I've used quartzite stones found in and near brooks that are flat enough to hone a Scandinavian grind without convexing it. You don't find them everywhere, but such stones do exist ;). That said, I'm not sure what grind predates the other, but I do know that stone tools that are ground into shape most often have a convexed edge.

yeah, i was kind of thinking the same oak. stone tools are ancient, and the convex seems to be most popular.

i kind of prefer convex anyway myself, it seems to be a bit hardier, and hold an edge longer than the rest.
i think the science behind it, is that theres more material closer to the point, so it can withstand more punishment.
its not as razor-like as a scandi edge, for the same reason, but plenty good enough for all tasks.

ill keep an eye out for some quartz stones.
now that you mention it, i have come across some in the past, that broke at the edge, exposing a 90 degree step, with 2 flat edges.

[dave budd]

hahaha. stupid scandi grinds causing problems? fancy that!

With the exception of some very specialist tools such as microtome blades, they are a modern phenomenon. Before Ray Mears started peddling the things 20 years ago, I don't think many people will have ever come across it. I've seen some single bevelled carving knives from Scandinavia in museums, but they are only a couple of hundred yeas old. Pretty much every knife I have seen from 3000 years of iron tool use and from every country is a wedge shape in cross section (be it full flat, sabre, hollow or convex) with a secondary bevel that can be sharpened on pretty much anything :happy-clapping:

[OakAshandThorn]

yeah, i was kind of thinking the same oak. stone tools are ancient, and the convex seems to be most popular.

i kind of prefer convex anyway myself, it seems to be a bit hardier, and hold an edge longer than the rest.
i think the science behind it, is that theres more material closer to the point, so it can withstand more punishment.
its not as razor-like as a scandi edge, for the same reason, but plenty good enough for all tasks.

ill keep an eye out for some quartz stones.
now that you mention it, i have come across some in the past, that broke at the edge, exposing a 90 degree step, with 2 flat edges.
Both quartz and quartzite are notorious for step/hinge fracturing, and there's really no way to get around it, unless you fracture the piece down to a rough shape and then refine it by grinding. Native artifacts made from quartz are rather thick and variable in the way they were shaped. Quartz "behaves" differently than cherts and flint...it tends to have a mind of its own.
I think you'll like this:


https://www.youtube.com/watch?v=sCFR0-C7kOc

[ChrisCraft]

these knapper guys always make it look easy.

ive tried a couple times with flint, and im useless at it, lol. i deffo need alot of practice

[OakAshandThorn]

these knapper guys always make it look easy.

ive tried a couple times with flint, and im useless at it, lol. i deffo need alot of practice
His advantage is that he uses a method called indirect percussion, which is a lot more precise and controlled than using a hammerstone or an antler/wooden billet. He uses two plastic rods tipped with copper, one with a wider copper tip for more flake removal. Flint is forgiving, just be glad you aren't pounding on quartzite or agatised coral :P