Has anyone tried to peen sharpen a blade

not2sharp

not2sharp

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Peen sharpening involved hammering and drawing the edge to a thin sharp layer, as an alternative to reducing the blade with abrasives.

Here is an article on peen sharpening:
http://www.scytheconnection.com/adp/docs/peening.html

I have not tried this but it looks like an interesting mechanism. I suspect this will work primarilly with relativelly soft steels. Has anyone tried this?

n2s
 
Umm it seem to be a method only use to sharpen Scythe. Not sure how well it would work on a modern style knife with harden steel. It looks to be a good method for those long curved blades of a scythe that could be harder to sharpen use a stone on. I found one store selling all the bits you need to "Get started In Peening" and some of the stuff was expensive . Looks like a Lost art tho would be fun to give it a try, hell I did not know that anyone even used scythes since the gas powered string trimmers are cheap and much safer than swinging a 2 foot long knife at your feet to cut some grass.
 
MadMullet said:
... hell I did not know that anyone even used scythes since the gas powered string trimmers are cheap and much safer than swinging a 2 foot long knife at your feet to cut some grass.
Click to expand...

You don't actually swing it. You grasp a clump of grass/grains, hook the scythe around it and pull the knife through to harvest.

n2s
 
OT: There's some threads about somewhere dedicated to scythes. Videos popped up in them of contests to see who could mow an identicle patch of overgrown grass faster - a guy with a scythe, or a guy with a gas trimmer.
 
I've sharpened old beater machetes this way. Using an anvil and a mallet. This was about 20 years ago though. The method works, along with a bit of filing.
 
That method is only intended for use on VERY THIN and VERY SOFT blades. American pattern scythe blades, for instance, are much harder than Austrian pattern scythes and will crack if you attempt to peen them. A knife is not going to respond well to the technique.

While I can't claim to be an expert (yet) I've put a lot of research into scythes, their history, and usage, and would not recommend trying to peen a knife blade. The technique WAS used on bronze tools and weapons to work-harden the edge region, however.

For the record, here I am mowing with my trusty American scythe. :)

[video=youtube;SEiqsxJj57o]http://www.youtube.com/watch?v=SEiqsxJj57o[/video]
 
I've tried peening a scythe blade at least, and even a specialized peening anvil, it was the most difficult sharpening-related task I've attempted to date. I might just crack one of these days and get one of those lazy man's peening rigs. :D

But I'd concur with the consensus here, most knives these days will be too hard for any such cold working of the edge.
 
Peening will work with soft steel tools like corn cutters, machetes, etc. Sometimes the edge will work harden and crack though if you beat on it too much. Come to think of it, it might work on some of those old soft stainless kitchen knives....

Peening is still used as a sharpening technique on Japanese plane irons, when the cutting edge has been worn/ground back to the hollow on the back of the iron the soft iron body is hammered down to flex the hardened steel bit into the hollow, so less steel has to be ground off to flatten the back of the iron . You can even buy specialized jigs to aid in the process. How this does not crack the high carbon bit I don't know, but it is common practice so it must work.

Many "old time" carpentry tools were sharpened by having a blacksmith "draw out the edge" when the cutting edge had been sharpened to the point that the edge was too thick. Better to move the metal around to extend the life of the tool than grind off a huge amount to thin the edge. But this involved heating the tool to forge it and a heat treat cycle to re-harden the tool so it was much more than just "peening"
 
I'm late to the game but, I hardened tools made from baling wire by peening the wire with a hammer. The tools were for pulling 44 pin CPU chips out of their sockets when chips were too new to find tools for them. The shop didn't have a heat-treating oven and I tried tempering them with a torch in oil and water and the wire lost heat too fast so I just beat on it until it held its shape under load. I broke a half dozen from brittle failure before I got it right.

I am pretty sure it was CFI wire but it was 25 years ago.
 
I once sharpened an old Schrade I picked up with a variation on peening.
There were pits right on the cutting edge, so I started by somewhat forcibly drawing the edge across a piece of carbide, back and forth, to kind of peen metal over into the pits. Then I touched it up with a stone.
It actually worked quite well. Schrade 1095 carbon responded to the mild peening nicely.

If course, that would not work with harder, more brittle steel. Some toughness and malleability would, of course, be necessary.
 
Sounds more like burnishing, a common practice when using cabinet scrapers.

Parker
 
Yeah that work on the Schrade was burnishing, not peening. Peening is using a hammer and anvil surface to cold-forge the edge, drawing it out into the desired geometry.
 
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