Forging spring shears "Japanese scissors"

Greenberg Woods

Greenberg Woods

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Dec 27, 2013
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Hey Guys. Recently I found I am moving out of the dorms and into a house and will finally have lots of space to make my own garden. Being the weird, nerdy and perhaps obsessive guy I am, I thought it might be interesting to make a pair of gardening shears in the japanese spring style.

I was wondering if anyone has experience making them, and my rough plan was to forge to beveled areas, grind a bevel, forge down a narrow strip of steel that I would then bend into the spring back and then quench the blades.

I assume the advise is going to come from someone who specializes in japanese blades, or Stacy. Our dear Jack of all trades and master of damn near most.

If you are wondering what Im talking about, these are it.
https://www.youtube.com/watch?v=4E7ZYmBYLUg

The video is very interesting. Not much use in terms of making anything, but its relaxing and well put together.
 
awesome! I think Ive got that bug now,
 
So funny, I was just in a knife store yesterday where the entire forging progression of Japanese shears from start to finish was displayed on the wall in a sort of "story board." I wish I had taken a picture of it! The main body of the shears were jigane (which usually means ductile iron -- I was surprised that this part also forms the spring) and the cutting edges are carbon steel (hagane) forge welded on, in the same construction as Japanese single bevel knives. Next time I'm there, I'll try to get a photo of it.

The jigane began as square stock, forged flat on both ends where the hagane would be welded on. The spring portion in the middle was then also forged flat, but at a perpendicular to the two blade ends.
 
Tenebr0s said:
So funny, I was just in a knife store yesterday where the entire forging progression of Japanese shears from start to finish was displayed on the wall in a sort of "story board." I wish I had taken a picture of it! The main body of the shears were jigane (which usually means ductile iron -- I was surprised that this part also forms the spring) and the cutting edges are carbon steel (hagane) forge welded on, in the same construction as Japanese single bevel knives. Next time I'm there, I'll try to get a photo of it.

The jigane began as square stock, forged flat on both ends where the hagane would be welded on. The spring portion in the middle was then also forged flat, but at a perpendicular to the two blade ends.
Click to expand...

I figured the process would be something like that.

What I wonder is if it can be done out of a single bar of say, 1084 and only quench the edges.
 
Sam ? Ithink he's still lost in Baltimore.
Would ductile iron be enough spring for that ?
 
Based on my observations, and some similar tools I have worked on (spring style sheep shears):

The "spring" doesn't need a lot of springiness, and certainly should not be very strong in flex resistance. In many Japanese blades, the term "ductile iron" is more like what we would call low carbon steel. Even 1030 will harden enough to be springy to some degree.

You could make it out of a .065" thick bar of 1095 and get a pretty good pair. It would definitely be springy. I would make one that way as a practice run. 1/2" square stock would be fine.

If you want a more authentic Japanese shears set, I would use 1/2" square 1050 for the main stock and forge weld 1/8" blue steel#2 or super blue to it. Make sure you put the edge steel on opposite sides or you will be twisting the piece to get them opposing. If using a two-layer steel billet, you will have to twist the final shaped piece. Shape into a double ended butter knife ( for lack of a better description). Draw down the middle to get it long enough and thin enough to be the handles and the bend. Leave it straight for now. Work the shears blades until they have opposing lapped flats and edge bevels around 60 degrees. I would leave the final shaping of the shears and shanks for the last step, as all that matters now is the flatness of the shear blades and the angle of the edge bevels. Once that is done, harden the shears and about 2-3" up the shanks. You can do this best with two separate HT quenches ( each end), followed by one set of tempering heats. Re-lap the flats and tune up the cutting bevel edges to the desired angles. Make the bend in the middle around a round mandrel and adjust the position of the shears to get the desired shearing effect. Test the cutting on paper and on grass. You can just work harden the bend by hammering it, or heat up and quench for max hardness. Temper the bend at 350F to remove excess brittleness. Make the final adjustments and clean up the shape on the belt grinder. Make the final force required for cutting by thinning the bend area as needed.

As an alternative, you might be able to find an old set of sheep shears on eBay for a low price and re-shape it for your purpose.
 
Thanks Ben. I spent the rest of the evening last night watching Japanology videos... Good stuff.
 
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