Who else uses a scythe?

I've been working on lots of big projects! Seen here was an initial test of bending an ash dowel using 29% ammonium hydroxide.

In the 1960's it was discovered that anhydrous ammonia gas could be used to dissolve the hydrogen bonds in the lignin between the cell walls, allowing them to slip past one another. During drying those bonds then reformed, fresh, causing the wood to now behave as if it had grown that way. Through the 1970's more research was done using anhydrous ammonia, either as a gas or under pressure as a liquid, but handling anhydrous ammonia is dangerous and the method never caught on. However, little research has been done on the use of ammonium hydroxide (aqueous ammonia solution.) After finding some minor indicators that ammonium hydroxide might still produce results while being much safer (if still requiring PPE and good handling practices) I decided to perform a proof of concept experiment.

The solution actually worked a little TOO well and I over-soaked the piece (a little less than a week--I wanted to make sure the effect, if any, couldn't be missed), causing it to immediately begin pulling apart during the test bend due to the lignin being too thoroughly dissolved. I now have parts on the way to construct a more proper treatment tank for further tests. The fact that the wood took so severe a bend without breaking, and with only hand pressure at room temperature is remarkable, and I look forward to further tests, which will include the use of better developed bending forms for less severe bends, using steel straps to support the exterior of the curves to force compression, combining steam bending with the ammonia soaking, and varying soak times.

The wood has only been out of the tank a couple of days and is already down to about 20% moisture content in most spots. The ammonia evaporates out remarkably quickly, and the remaining piece is quite sturdy despite the loss in thickness.

Safety Note: While much safer than anhydrous ammonia, 29% ammonia hydroxide requires the use of an ammonia-rated respirator, splash goggles, apron, and gloves to safely handle, chiefly to protect from the fumes. Standard household clear ammonia cleaner is only a 1-3% solution.

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FortyTwoBlades said:
I've been working on lots of big projects! Seen here was an initial test of bending an ash dowel using 29% ammonium hydroxide.

In the 1960's it was discovered that anhydrous ammonia gas could be used to dissolve the hydrogen bonds in the lignin between the cell walls, allowing them to slip past one another. During drying those bonds then reformed, fresh, causing the wood to now behave as if it had grown that way. Through the 1970's more research was done using anhydrous ammonia, either as a gas or under pressure as a liquid, but handling anhydrous ammonia is dangerous and the method never caught on. However, little research has been done on the use of ammonium hydroxide (aqueous ammonia solution.) After finding some minor indicators that ammonium hydroxide might still produce results while being much safer (if still requiring PPE and good handling practices) I decided to perform a proof of concept experiment.

The solution actually worked a little TOO well and I over-soaked the piece (a little less than a week--I wanted to make sure the effect, if any, couldn't be missed), causing it to immediately begin pulling apart during the test bend due to the lignin being too thoroughly dissolved. I now have parts on the way to construct a more proper treatment tank for further tests. The fact that the wood took so severe a bend without breaking, and with only hand pressure at room temperature is remarkable, and I look forward to further tests, which will include the use of better developed bending forms for less severe bends, using steel straps to support the exterior of the curves to force compression, combining steam bending with the ammonia soaking, and varying soak times.

The wood has only been out of the tank a couple of days and is already down to about 20% moisture content in most spots. The ammonia evaporates out remarkably quickly, and the remaining piece is quite sturdy despite the loss in thickness.

Safety Note: While much safer than anhydrous ammonia, 29% ammonia hydroxide requires the use of an ammonia-rated respirator, splash goggles, apron, and gloves to safely handle, chiefly to protect from the fumes. Standard household clear ammonia cleaner is only a 1-3% solution.
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That's fascinating! I hope you get a workable method. It would also be helpful if you had a way to test modulus of rupture before and after treatment. Even if it lost 25% you'd still have a good snath with just the shape you wanted.
 
Square_peg said:
That's fascinating! I hope you get a workable method. It would also be helpful if you had a way to test modulus of rupture before and after treatment. Even if it lost 25% you'd still have a good snath with just the shape you wanted.
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Tests performed using anhydrous ammonia I was digging up actually saw a strong improvement in modulus of rupture along with a corresponding increase in breaking strength, a slight increase in density, and a slight reduction of elastic modulus, and treated wood shrunk and expanded less with changes in moisture. However, it appears as though the particulars of treatment can have a strong influence on the degree of change so much remains to be seen! It's not very well researched, to the point where many studies mention how few studies there are in their introductions.
 
Some further testing. It's only ~42° F out and this was a 3-day soak bent cold. Still a tight radius for this test before I bother building more involved forms. The runout on this piece is atrociously bad and would normally not be considered as a candidate for bending. In the attempt to see how far I could take it I did end up breaking it but figured out a few tricks; bending it while the surface still appears wet causes surface grain to lift, but waiting the couple of minutes to bend it after the surface has "dried" in appearance keeps that from happening. Incredible that it bent cold this far and then held its shape after only about an hour in the form, despite the breakage, and the break isn't all the way through.

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I'm having some proper blanks made up locally to do further testing--these were just some pieces I had on hand. They'll be nice long 72" staves with a 1-1/2" square end for 16" followed by a transition to 1-1/4" round. Should make excellent blanks for testing and will also make great handle blanks for things like mounting socketed cazanga machetes and the like.
 
Continued experiments in ammonia bending has yielded positive results. This was done cold, no steam or heat. There's still a lot to dial in with the process and I need to build more clamps, but I'm fairly confident I'll eventually be able to easily bend custom snaths with traditional curves once I get it all sorted out.

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Not an April Fool's joke--for the first time in years I finally got around to updating the beginner's guide to American scythes. The changes aren't drastic, but add additional detail, clarification, or corrections of what I now consider best management practices. I hope to do a few additional edits ahead of beginning work on separate documents detailing antique restoration and advanced technical tuning.
 
FortyTwoBlades said:
Not an April Fool's joke--for the first time in years I finally got around to updating the beginner's guide to American scythes. The changes aren't drastic, but add additional detail, clarification, or corrections of what I now consider best management practices. I hope to do a few additional edits ahead of beginning work on separate documents detailing antique restoration and advanced technical tuning.
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I've been meaning to buy a scythe and learn to cut grass with it, looks like I get to read the updated beginner's guide!
 
I've been using my scythe the past couple weeks- rain has turned my front yard into a soggy swamp, so I throw on the muks and grab the scythe.
I think my technique is improving, and in general I'm cutting grass better.
I still feel like I have a long way to go.

I have to go re-read Benjamin's how-to, because I'm sure I don't have the perfect technique yet. I've tried to make the blade as thin and sharp as I can with the BYXCO scythe stones.
 
EngrSorenson said:
I've been using my scythe the past couple weeks- rain has turned my front yard into a soggy swamp, so I throw on the muks and grab the scythe.
I think my technique is improving, and in general I'm cutting grass better.
I still feel like I have a long way to go.

I have to go re-read Benjamin's how-to, because I'm sure I don't have the perfect technique yet. I've tried to make the blade as thin and sharp as I can with the BYXCO scythe stones.
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The initial grinding is the toughest part! I can't recall if you had picked up a grinding point or had grinding work performed some other way. The scythe stones are more for honing and maintaining the bevel set in the grinding phase. You'll want your bevels roughly 1/4" wide on most blades, depending on thickness and prior existing geometry.
 
FortyTwoBlades said:
The initial grinding is the toughest part! I can't recall if you had picked up a grinding point or had grinding work performed some other way. The scythe stones are more for honing and maintaining the bevel set in the grinding phase. You'll want your bevels roughly 1/4" wide on most blades, depending on thickness and prior existing geometry.
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how does one perform that grinding without a grinding point?
I'll go in for the grinding point if I gots to, but if I could use what I gots, I'd be happier- but if you strongly recommend using that grinding point, I'll do that

I'm close to ~1/4 inch, but probably not all the way there.
 
EngrSorenson said:
how does one perform that grinding without a grinding point?
I'll go in for the grinding point if I gots to, but if I could use what I gots, I'd be happier- but if you strongly recommend using that grinding point, I'll do that

I'm close to ~1/4 inch, but probably not all the way there.
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Basically you need your bevel at only around 7-9° per side (so only a little above flat) and if it's properly thin and sharp in plain grass you shouldn't feel the cutting action much if at all--it should be more like sweeping with a broom and grass just "magically" falls. Technique plays a role in that for sure, but if you can feel the grass "scrunching" in the cut it's probably a sign you're a little thick in your geometry. The way you'd normally grind it would be on a water-cooled slow speed grinding wheel but the grinding points are an inexpensive alternative that gets you about 95% as good of a geometry at a fraction of the cost and you just chuck it up in an electric drill. The ones I stock are ones specifically designed to cut cool rather than putting shape retention at the priority like most hardware store grinding points do, so there's less risk of burning the edge. Once that bevel is properly set, future grinding takes very little time, but the first time will probably take 15 minutes or possibly more depending on the as-found state of the blade and how thickened up the edge geometry is.
 
FortyTwoBlades said:
Basically you need your bevel at only around 7-9° per side (so only a little above flat) and if it's properly thin and sharp in plain grass you shouldn't feel the cutting action much if at all--it should be more like sweeping with a broom and grass just "magically" falls. Technique plays a role in that for sure, but if you can feel the grass "scrunching" in the cut it's probably a sign you're a little thick in your geometry. The way you'd normally grind it would be on a water-cooled slow speed grinding wheel but the grinding points are an inexpensive alternative that gets you about 95% as good of a geometry at a fraction of the cost and you just chuck it up in an electric drill. The ones I stock are ones specifically designed to cut cool rather than putting shape retention at the priority like most hardware store grinding points do, so there's less risk of burning the edge. Once that bevel is properly set, future grinding takes very little time, but the first time will probably take 15 minutes or possibly more depending on the as-found state of the blade and how thickened up the edge geometry is.
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Sounds good- looks like I'm going to have to put in an order!
You've described exactly what I'm experiencing.

Out of curiosity, what did they use for this activity, historically?

Sounds like the user sets the grind, then use & hone until the angle gets too steep, then grind again?

Forgive me if this is covered on your website, but currently my work computer is my only internet enabled device during work hours and unfortunately the work firewall considers your website to be "weapons or bombs" :rolleyes:.
 
EngrSorenson said:
Sounds good- looks like I'm going to have to put in an order!
You've described exactly what I'm experiencing.

Out of curiosity, what did they use for this activity, historically?

Sounds like the user sets the grind, then use & hone until the angle gets too steep, then grind again?

Forgive me if this is covered on your website, but currently my work computer is my only internet enabled device during work hours and unfortunately the work firewall considers your website to be "weapons or bombs" :rolleyes:.
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Correct--you grind the blade when the bevel geometry has been thickened up too much to mow with ease anymore. Barring actual edge damage, and with good honing practices, this only needs to be done 1-3 times per season. Otherwise you maintain it with a stone. Historically a slow speed wet grinder would have been used, and would have been used for maintaining countless farm tools, but these days many folks don't have much use for one other than scythe grinding so unless you plan on using it to maintain other tools like chisels etc. even a cheap one is a hefty investment at about $200. So a grinding point is a lot more accessible.
 
welp, so last night I got out my bull thistle american scythe stone, and I went to town on my blade.
I found where the original bevel was set and started working away. I worked through three movies, The Road, Dawn of the Dead (remake) and No Country For Old Men.
I'm so close, but I'm convinced the way to do it is with the grinding point.

Order placed.
I'll also get to experiment with that HDPE sheath material, so that's a bonus.
 
Last night I watched a video "Food Around The World" about a woman in the mountains of the Ukraine. She took her scythe out to her garden had a stone which she used to sharpen it and did here cutting. What got my attention was the blade had to be at least a meter long. Seemed a lot longer than the scythes I have seen on this forum. Are European scythes longer than ones in the USA? John
 
John A. Larsen said:
Last night I watched a video "Food Around The World" about a woman in the mountains of the Ukraine. She took her scythe out to her garden had a stone which she used to sharpen it and did here cutting. What got my attention was the blade had to be at least a meter long. Seemed a lot longer than the scythes I have seen on this forum. Are European scythes longer than ones in the USA? John
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Not particularly. If anything they average a bit shorter when it comes to grass blades! But mostly you don't see blades over ~36" (~91.4cm) because of the fact that you either have the blade cutting the same amount of material as a shorter blade with a more aggressive slicing action OR will be taking a larger bite, and a larger bite means more work = more energy per stroke = more likely to get bogged down in the cut, plus worse leverage on the snath and tang if you mess up a cut. Long blades tend to be best used either for competitive mowing or for lawn work/mowing large spaces with sparse growth that are annoying to mow with a shorter blade, or spaces with light vegetation that won't absorb the force of the stroke so badly as mature heavy vegetation.
 
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