primitive blade edges

[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

[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:

[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