How to sharpen American scythes

FortyTwoBlades

FortyTwoBlades

Baryonyx walkeri
Dealer / Materials Provider
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A little video I wrapped up today on the subject.

[video=youtube;yK8KVgM7WAM]https://www.youtube.com/watch?v=yK8KVgM7WAM&feature=youtu.be[/video]
 
:) Interesting video
What kind of feedback are you looking for?

It might be a good idea to post a transcript in the description , this is how the automatic transcript starts
0:08 sharpening aside takes place in two stages battling and honing battling is
 
I was posting the video more for informational purposes than for feedback, per se, but I do always appreciate questions/comments/suggestions. A transcript wouldn't be terribly useful, though, as many of the phrases wouldn't make much sense when stripped of their visual context, and in almost all cases in the video itself the narration is captioned verbatim. :)
 
FortyTwoBlades said:
I was posting the video more for informational purposes than for feedback, per se, but I do always appreciate questions/comments/suggestions. A transcript wouldn't be terribly useful, though, as many of the phrases wouldn't make much sense when stripped of their visual context, and in almost all cases in the video itself the narration is captioned verbatim. :)
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:) see the thing with "caption" is you can't copy/paste it

so you raise a burr on the grindwheel using 7-9dp?
and you remove burr by increasing angle (micro-beveling) and using the "chine" like an angle guide (like a straight razor)? And you just do one pass?
 
As previously noted, though, the dialogue only makes sense when paired with the visuals. It's not copy/paste friendly instructions.

The edge is brought to an apex on the wheel at 7-9° per side, and the formation of a burr is something that simply often happens in the process rather than being something you actually shoot for. The stone does not contact the chine in most cases, but rather the edge apex and bevel shoulder are in two-point contact with the whetstone due to the difference in respective radii between the grinding wheel (5" radius) vs. the whetstone (most averaging about an 11" radius.) I'm not sure what you're asking as far as passes go...do you mean with the grinding wheel or with the whetstone?
 
FortyTwoBlades said:
As previously noted, though, the dialogue only makes sense when paired with the visuals. It's not copy/paste friendly instructions.
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:) Yes, you've said that, I disagree :) people like copy/pasting stuff :)
For example you talk about kind of grinding wheel and materials for jig, sure the visuals help, but so does copy/paste for finding those materials; also having a transcript works as an outline to remind one of the visuals ...
at end you give a diagnostic tip/step, if you're not cutting grass at low speed then , this didn't happen, that didn't happen ... but the visuals only consist of cutting grass, so visuals not most important for that part
... but to each his own :)




FortyTwoBlades said:
The edge is brought to an apex on the wheel at 7-9° per side, and the formation of a burr is something that simply often happens in the process rather than being something you actually shoot for. The stone does not contact the chine in most cases, but rather the edge apex and bevel shoulder are in two-point contact with the whetstone due to the difference in respective radii between the grinding wheel (5" radius) vs. the whetstone (most averaging about an 11" radius.) I'm not sure what you're asking as far as passes go...do you mean with the grinding wheel or with the whetstone?
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i'm kind of asking, when do you stop grinding (wheel and stone and stick)

this is what I get from the video
for grinding with wheel, stop when its balanced
then its time to remove the burr
for stoning, this is removing the burr and setting scratch pattern, you make one pass on coarse, one on fine
for slapstickining :), you make one pass

you end with a tip about, if its not cutting grass easily then you haven't got appropriate bevels, not fully apexed, apex not centered, burr removed, scratch pattern established, apex sufficiently refined

but how do you know if you've done those things? if you've "fully apexed"?

I guess it helps to be familiar with sharpening already :)

its one of the better videos i've seen, very thoughtfully planned out, good camera angles, great info / obvious you've spend a lot of time with scythes :)

as extra info, why is "centering" important? and the "scratch pattern"?
 
With grinding you stop when the bevels are set at the right angle and they are brought fully to an apex--the grinding has progressed all the way to the edge rather than stopping short of it.

For passes with the whetstones and whipping stick, it's done to the degree necessary to produce the desired result, which is usually 1-2 passes depending on the amount of a burr that needs to be removed, the hardness of the steel, etc. This varies blade to blade. The apex must be centered in the web because, as described, many American scythe blades are laminated. If the edge is not evenly ground so the apex sits in the middle of the web then the soft cladding iron or mild steel will be comprising the edge instead of the cutlery steel core layer, and so it will not hold its edge properly. This is not important on blades that you know are not laminated, but if there's any question about it (and there often is, especially for the less experienced) then it's best to treat it as if it is laminated because evenly grinding an un-laminated or whole steel blade does it no harm, but the opposite is not true. Setting the scratch pattern is important because of the toothy gripping effect it has on the grass. Some grasses, particularly hard, fine, waxy-surfaced ones really like to try to slip off the edge. A properly set scratch pattern helps prevent that. In some mowing conditions you may want a coarser or finer scratch pattern, but you always want it facing heel to toe. If it were facing the other way it would be like trying to cut on the push stroke with a Japanese saw. You'll cut some wood, but it'll be much slower than doing so in the proper direction because the pattern isn't properly opposing the target material.
 
For a text-based guide, there's this living document HERE. I have yet to fully update it with some of the details in this video, but they'll be there soon.
 
Filing works for most blades as long as you draw-file so you can get a properly low angle, but some blades are so hard a file skips off 'em! Nothing like a good grinding wheel around a homestead. It's been said that the state of a farm's management could be judged by how carefully the grinding wheel was hung because the smooth operation of the farm so depended upon it!
 
Another great video, thanks!

How often do you generally have to touch up, assuming you haven't banged off of anything hard?
 
I'll usually use the whipping stick about every 10-15 minutes, and the fine stone every third stop. The usual cycle is something like: whipping stick-->whipping stick-->fine stone, then whipping stick. I use the medium or coarse stone only if I run the edge into dirt or I feel I need to reset the scratch pattern.
 
It depends on the blade, but very high for low-alloy carbon steel. High 50's at least, in most cases. We all know how glassy-hard vintage American axes were, and historical notes on heat treating scythes dictates that they should be "a little harder than an axe"! Whole-steel blades are usually a little softer than laminated blades in order to lend themselves a bit more toughness than would otherwise be possible.

I have some pieces from a fatally damaged blade that I'd like to get hardness tested.
 
Lieblad said:
Speaking of whipping stick,
I remember but as a 10 years old kid my grandfather making a wooden dowel coated with what I think now was linseed oil then sprinkled with dry soil. Did not understand at the time.
But makes sense, dirt embedded in the porous wood adding a touch of abrasive.
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Yup! Many use something tacky to adhere a bit of fine grit to the stick, though I just use a fine stone and finish on the bare wood. In the UK they used what's known as a strickle, which was much like a whipping stick but with little divots on its surface (often made by knocking the wood into the teeth of a saw) and they would use a bit of grease as the adhesive and roll it in fine sand.

Btw, if one is serious about mowing, they need a couple scythes & selection of blades to match the specifics of task.
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Absolutely. I have three snaths I regularly keep rigged up and have a handful of different blades in rotation. :)
 
You're very welcome! As I mentioned, it's a living document and gets updated whenever I have the time, rare though that is. I have a lot more I need to write down.
 
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