Tuesday, November 16, 2010

Forge your own scythe blade

A question about a previous post (Brubaker scythe blade, Made in USA), followed by the response from Jack Brubaker:

Is there any chance you could provide me with a fuller description of how you went about making the scythe blade itself?  
I have been scouring old books and the internet to no avail for  information and instruction on this aspect of blacksmithing.  I am interested in the details of this as I have no machinery, such as a foot hammer, to pursue this project.  It is my hope that with more details I might be able to reproduce the same effects with simple hand tools. 
-- Carl

I want to write up my experiences with blade forging more completely after I have more practice myself. But, what follows are a few notes that might help. 

It is certainly true that scythes used to be forged without machinery. There is probably somewhere a shop on the fringe of world trade where this is still being practiced, perhaps many. My guess would be that the procedure would be similar to that used when forging with a power hammer, but I may be wrong. Look at the images on the Geyerhammer site to see the steps in forging. 

The only part that really surprised me in watching the smiths at Schrockenfux was the way the blade held the preset curve while being hammered thin. My experience with knife making was that in forging a blade the greater hammering needed to thin the cutting edge to its slight thickness caused the blade as a whole to curve as that part of the blade grew in length more than the thick back of the blade. It is necessary to over compensate for this distortion by curving the blade into a C shape first so it will straighten out as it is thinned.  

The scythe smiths I watched did not have this problem at all. They started with the blank bent to the curve they wanted the final blade to have and kept that curve throughout the forging process.

Having done it once I now see that the difference between a knife and a scythe is that the knife blade has a wedge shaped cross section and a scythe has a thick back but is nearly even in thickness across the rest of the cross section.  I assumed that the thick back would constrain the back from growing in length as the rest of the blade is thinned and grew in length. Two things happen to prevent this from being a problem. First the thick back holds it's heat well because it is thick and just stretches some as the blade is forged. Second the blade is forged with a top die that is canoe shaped hammering on a flat bottom die. (The pointed end of the top die is needed to form the V shaped section between the back of the blade and the diagonal "deer's tongue" that reinforces the connection between the blade and the tang.) 

The long narrow shape of the top die acts as a fuller to move the metal primarily in one direction, to widen the blade as it is thinned. So far this is a lot like knife forging. The difference is that only a small square section is left to form the back while the rest of the blade is hammered very thin. The shape of the blade is watched by the smith and can be controlled by how much hammering is done near the back and how much is done near the edge. If they are balanced the blank will hold its pre-set curve. If the curve goes off it can be brought back with more hammering near one side or the other as if the back was not there.

To hand hammer a scythe blade there could be several approaches. One would be to try to use the cross pein to spread the blade taking care to not hit the back. Start by fullering a groove next to the back to define it's shape and use the cross pein to hammer the rest. This will be a very tedious process requiring many, many heats, unless you are a lot stronger than I am. In the act of taking so many heats on increasingly thinner metal some of the carbon may be burned out of the steel, so the result will be unpredictable.  Heating in a gas furnace rather than a coal fire will probably help limit the accumulated damage to the metal since the sulphur in the coal attacks the steel.

Another process would be to start with a very thin blank that could be cut to shape, and form the back by folding over the back edge once and then bending the doubled metal up at 90 degrees to the blade. There are blades being made this way in large forming dies. It can be done at the anvil with a V block in the hardy hole and working the fold down into the V with a cross pein hammer. Once the fold is formed, hammer it closed on the face of the anvil and form the next fold in the V block. This time just true up the fold at 90 degrees in the V block.

If there are still blades being hand forged somewhere they are most likely being hammered by a team of smiths. The master holding a top fuller and two or more strikers swinging sledges to drive the fuller as the master moves the blank under the blows. This can be a quite powerful process but requires experienced strikers and a lot of team work to really move the metal very much per heat. 

Walter Blumauer from the Geyerhammer Museum told me that in the old days in Austria, a scythe shop without power hammers with about 25 employees (smiths, polishers, finisher, packer, and foreman-owner) would make 25 blades a day. Using water hammers (since the 1500s), each smith could forge 200 to 250 blades a day. When he had met his quota he was done for the day and went home.

The V block seems to me to be the most important tool one would need to have to forge a blade by hand at the anvil, that and a strong arm. It is used to refine the form of the back in place of the double acting power hammer (that strikes both vertically and horizontally with alternating blows) used in the Austrian scythe shops.

One thing worth note is that in the modern practice the entire length of the blade (all but a short end that is hand held by the smith) is forged all over evenly so that the whole blade emerges from the blank at once. Working by hand this will be more problematic since only so much can be done at one heat. If one section of blade is hammered in one heat when the next section is forged there will be a problem of discontinuity where the two forged section merge and there will often be a spot where the blade is less wide where the two sessions of forging merge.

Over lapping hammer blows have a very interesting effect on the way the metal flows (what direction the metal moves under a series of blows). For the sake of example, if a square but flat hammer is used to make a series of heavy penetrating blows, each slightly to the right of the one before it, the metal will move to the right in growth. That is not to say that it won't move out in all directions as is expected from a hammer of this shape, just that there will be more spreading of the metal to the right than the other directions. This is caused by each successive blow landing on the right edge of the depression made by the previous blow. All the force of the hammer in concentrated on the small area where the next blow misses the last blow. 

The effect is the same as if a very narrow hammer face shaped like a straight pein hammer had been used. Scythe smiths use this effect to help control the movement of the metal. They also turn the blank at about 15 degrees to the top die and strike a line of blows down the area near the back or near the edge to both thin the metal and stretch those sides of the blade lengthwise. This can help control the shape of the blade. 

So for maximum widening of the blade, blows will be run in a pattern across the blank. For stretching the edge or back, blows may be struck in series that run up and down the blank along it's length (even though the die is still parallel to the blank). It is also possible to push out the back of the blade if it gets a little to straight (heaven forbid concave) by running a series of blows that start at the middle and move to the back, this will have the effect of pushing out the back. 

Don't worry too much about the exact width of the blade from the back to the edge. Keeping the shape and getting it thin is the main problem. If there is the right amount of metal to start with there should be enough width when the blade is well thinned. If there are excess bulges of metal on the cutting edge they can be trimmed off before final peining of the edge.

I hope to have time to make drawings of these hammering effects and tools that might help later this winter. Austrian blades are forged from 7 to 8 point plain carbon steel. Alloys would interfere with the cold hammering needed to set the tension in the blade in the Austrian method. I continue to use the blade I forged along side a new Austrian blade. I have had more tears in the edge of my blade. I don't know if that is a result of the blade not being hardened and tempered, or is because I used 10 point carbon steel, or because I use that blade for cutting tougher material since it is shorter and heavier. Because I often use it on heavier material I can't judge the blades one against the other effectively, but it remains a useful and effective tool.

-- Jack Brubaker

(Source:  Image "Sensenschmidt-1568" from Jost Amman and Hans Sachs, Frankfurt am Main, 

Sunday, August 29, 2010

Black walnut snath

From the mailbox at ScytheConnection.com, sent by the happy maker of a beautiful snath:

To the Vido Family,
I want to thank you for all the fabulous information you have published. Your web pages inspired me to construct a wild-wood "one-grip" snath. I used black walnut and ash from dead wood found on the property and antique hand tools found at a garage sale. I'm so glad I found and your website and decided to build my own. I would not have been able to do it without you. Thank you so very much.

Today, I completed the setup and mowed a section of very mature forage grasses and chickweed.  I am tickled with the results.

All the best,

Some initial comments from me about this snath
(Peter Vido might have other comments to add):

1.  The wood is attractive; the coloration is striking.

2.  The grip looks like it is set at a good angle (slightly toward the blade).

3.  The location of the grip looks proportionally close to the blade; I'd know more by seeing a photo of the snath being used and the resulting position of the user's body.

4.  With the curves, I can only guess at the hafting, but a more acutely hafted blade may give even better results.

5.  The tang steepness and the lay of the blade in use is likewise unknown to me at this point.

6.  My overall impression is quite positive, especially since the maker is so happy with the results.

Friday, August 20, 2010

Improvised whetstone holder

A container from the recycling bin and an old curtain hook can be combined to create an effective whetstone holder.

It's a close fit for a Bregenzer stone in this container, which can keep water from sloshing out.

A discarded scrap of aluminum foil or other material placed in the bottom of the container
can prevent the stone from eventually making a hole.

Monday, August 9, 2010

Brubaker scythe blade (Made in USA)

This was sent by Jack Brubaker, who forged his own scythe blade

and uses it with a homemade wildwood snath:

Today I found some time to attempt forging a blade from a one inch round of W1 tool steel. That is a simple carbon steel with 1% carbon. I know it is too much carbon, but I had it on hand. I used the largest of my hammers the 300 pound copy of a Beche. It happened to have a flat die on the bottom and a very round drawing die on top so I decided to give that combination a try. The top die is round with no real flat on the bottom so it was messy forging the zainen, but it was done with a little patience. I was just forging off the round stock rather than starting by cutting a blank so I didn't know how much steel I used. Once I had the stock roughed out and began spreading the blade it became clear that the top die was too round to form a sharp and crisp transition between the back and the thin body of the blade. I hammered the transition so that the edge of the back was the right thickness and the metal then thinned quickly toward the thin blade. This left the back more of a triangle then a rectangle but it did allow me to pull out the remaining metal into a fairly thin blade. I of course had some trouble with the blade forming the wrong curve (backwards at one point) but it all worked out in the end. To bend up the back I used a V block on the anvil and hand hammered the base of the triangular back down into the V with the cross pein of the hammer. This is a messy way to get it done as it left a lot of rough hammer marks. I envision a tool I can make that would do a much better job, but that will await more time to play. The first photo is of the blade at this point. As you see the round top die and the bashing with a hand hammer left a rough and uneven back. 

I then cut off the excess steel and refined the shape of the blade with more hammering. At this point it really began to look like a scythe blade and I got eager to try it out so rather than risk hardening and tempering now without a proper tank for the oil (I have a large stainless tank of oil for hardening hammer dies but it is round and not long enough) I elected to just hammer the blade cold as it was at that state. I thinned the edge on the anvil and hand hammered with the edge of a round flat faced hammer to get the effect of the dotting hammer and tension the blade. The blade stiffened up nicely and when pressed point against the floor it has a nice spring and curves with some grace. It is too stiff I think as a result of being a bit heavy. But not bad for a first try. I put it in a snath sharpened it some and it actually cuts grass. I doubt that it will hold an edge as well as a properly hardened blade but I am encouraged to try more of this! There was no way for me to form the tongue that reinforces the blade to tang area since my top die was too wide to form the narrow forged groove between the back and the tongue. I will have to make a better top die. The blade is 25.25 inches long(over all) and 3 inches wide at the beard. 

I have used my first home forged blade quite a bit along side a new blade from Rossleithen. It is lighter than an "American" blade but noticeably heavier that the Austrian blade (don't have any way of weighing them yet). There are things I look forward to doing better in the future, but I find it to be serviceable and it seems comparable in edge holding. I hope to be able to look back on this blade as my crude first attempt but first I need to wait until fall when I foresee having the time to work on blades in a more focused manner. I am inspired by an old blade I brought back from Austria (thanks to Walter Blumauer) that was made for the Middle-East market and is really thin and light but has a good tension and springy feel. I had the chance to try the first sample of a blade that Gerhard Walter designed and had the Rossleithen factory produce that is aimed at modern mowers. That blade is an interesting variation on standard European blades, mows very well, and has features I'd like to try out here in Indiana. 
So, there is much to do.

(Source:  Text and photos by Jack Brubaker, used with permission.)

Friday, July 23, 2010

Snaths for Long Blades

(This post was updated on July 31 with more commentary and captions, all from Peter Vido.)

I used this snath during the team competition in Denmark with a 90cm blade of a very conventional “in-circle” Austrian tang setting. I took it that summer to three more countries afterward and everyone who tried to mow with it was most impressed with how it behaved…

"Off-set to the right" is the arrangement I suggest for all long blades (75 cm and up), especially if they are somewhat heavy (500g or more)."

A long-bladed scythe, provided it is otherwise well adjusted, can indeed function very well and be a pleasure to use EVEN if the blade is not “off-set to the right”. However, that “already good” scythe will be still nicer to use if the blade’s horizontal balance is shifted to the right by a rather uncommon principle of snath design. 

I have made “wildwood” specimens incorporating this feature for about 8-9 years, and have advocated the concept widely in all of the 10 countries I’ve traveled with various demo scythes in hand. Although everyone who tried them was impressed with their feel and functionality, only a small fraction of snaths made subsequently (of wild wood or sawn lumber, either owner- made or in a production line) have incorporated this unorthodox principle. Breaking through walls of tradition has never been easy; and while this sometimes is a good thing, I wish it were different with regard to snath design.

Be that as it may, below are some examples of scythes with this favourable shift of the blade-to-the-right (of the straight line drawn between the position of the hands holding the snath).

Unfortunately the bottom end of this snath (made of naturally curved apple branch) is not shown here and consequently the picture is somewhat misleading. Past the point you can still see, the wood makes again a left hand turn and then continues in line with the shaft just below the grip. The end effect was an “off-set” of nearly 12” (30cm) to the right. I used this snath during the team competition in Denmark (shown above).

Similar principle, less accentuated. (this snath is now in Costa Rica)

Same snath as previous photo.

The wooden stick shows the amount of “off-set”. Here the lower half of the snath makes a right turn only (i.e. doesn’t turn left again as in the snaths above) to accommodate the typically open-hafted blade models. This blade has a very acutely-hafted tang, (similar to #103 in our catalogue).
Three snaths with off-sets similar to previous photo (and with Italian-made steeply hafted blades).

The snath’s bottom end turns right and then slightly left (still requiring a more acutely hafted tang than the common German or Austrian models.)

Ashley standing on the wall of her unfinished log cabin twirling Lance Harvell’s “4 gripper”. (described below)

This snath is made of sawn 1½” lumber deliberately steam-bent to follow the design principles outlined here, and at the same time accommodate blade models meant to go on straight (left-to-right) snaths. Lance Harvell (who may well be the best mower in the state of Maine) had the blank bent by a snowshoe maker and brought it here for us to finish.

He already had several wildwood snath/blade units from us, made along these lines, as well as others made later by himself.  He can appreciate the principle behind these snaths – especially so because he is an avid long blade user.

The blade he last picked from our limited old and long blade selection was 110cm and not exactly a light one… He wanted it fitted to the blank he brought along, and with backward-pointing grips, as he is accustomed to using. We did what he asked for, although I knew that a blade of that length and weight would feel more balanced with the grips pointing up and forward. So I improvised a little… and added such grips as well. Now he has a four-grip snath (interchangeable two pairs each, adjustable in two positions) – and the unit sure feels more ergonomic when held by the up and forward pointing grips.

This very narrow blade (85cm length) also has a rather acute tang setting. Note how the one-grip snath also makes a slight right turn. This is the unit in action here.

More samples of the off-set; (from right to left: with 75, 85 and 100cm blades).

The snath with the 100cm blade and a stick indicating the actual off-set.

Sideways view of the above – in order to address two additional concepts:Firstly, this snath is crooked in so many directions that it can be appropriately be referred to as “curved”. However, its bottom end curves downward – the opposite of the common curved snath models. My point in bringing this up is that a snath does not need to have the classical S shape curvature to work well. What is important is the relationship between the blade’s tang angles and the curvature of the wood, as well as the mower’s height and stance.

Second thing of note is the length of the extension (stem) on the lower grip – it is rather short; much shorter than the new generation of “ergonomic” snaths have them. I have tried to bring attention to this concept for several years now (see, for instance retrofit), but it is a somewhat uncomfortable topic among those who make and/or sell snaths. Namely, the tendency to come up with a “good for every purpose” snath (and claim it to be “the ultimate” in design) is very strong.
Admitting instead that a decidedly different grip arrangement is most suitable for trimming (with shorter blades) as opposed to field mowing (with longer blades and in somewhat lower stance/ posture) has not been popular, because it would make the scythe seller’s job more complicated and inevitably less profitable…
Be it as it may, the truth is that cutting and pushing more matter at a stroke (the natural by-product of using long blades) is notably easier if the right hand grip has a short, rather than long stem (extension).
At least some of the Swiss had that figured out long ago, because many of the mountain snath models still produced today have very short-stemmed grips.
In any case, Ashley – who is a fussy girl when it comes to scythes, and for whom I made this snath – has been pleased with how the unit functions…

(Source:  Photos and text from Peter Vido, used with permission.)

Saturday, July 17, 2010

Grain cradle design from Slovakia

These photos show the classic type of grain cradle used in Central Slovakia.


This simple design requires only a short length of chain, a suitable tree branch (or sapling), some cord, and a screw at the end of the one-grip snath.

The loop of chain is used to loosely attach the branch to the snath, as shown in this photo.

Moving the branch into position will then tighten the chain and hold the branch firmly against the snath.

When the branch is perpendicular, the chain is tight and the branch starts to bend.

The snath grip acts as a brace to hold the branch in place while the scythe is being used.

The cord is tied to the branch and looped around a screw at the end of the snath.

After making easy adjustments to the length of the cord and the position of the chain, the grain cradle is ready for use.

Peter Vido has this to say about grain harvesting and this cradle design:

"This rather quickly written piece on a very pertinent subject is meant as a provisional response to the growing interest in the grain harvesting scythe, often referred to as a “cradle scythe”. 

To begin with, I’d like to present some “facts” (call them opinions if you wish), which I intend to substantiate here at a later date.

  1. For harvesting relatively small (family bread supply- size, for instance) plots of grain, the sickle (rather than the scythe) may well be the tool of choice.
  1. For larger acreages of grain than you may feel like tackling with a sickle, the grain-harvesting outfit traditionally used in Central Slovakia is a relatively simple and efficient alternative.
The body of the cradle consists of a green (and thereby flexible) hardwood branch or thin sapling and a piece of string. (The wooden piece used in these pictures is a branch of a wild plum – hence all the knots.) The string is tied to the end of the branch as well as a small nail/screw/staple at the lower end of the snath. By lengthening or shortening the string, the branch is pulled into a position most suitable, depending on the height of the grain, to hold the cut stalks. The weight of this cradle is a fraction of the more complicated contraptions – and, most importantly – is easily owner-made!

  1. None of the snaths mounted with a cradle that I have seen in museums in several countries (as well as pictured in books) had the lower grip facing backwards (meaning toward the person operating them). This was the case even in regions where the general purpose (“grass”) scythes had their grips pointing backwards – the way the now popular version of Austrian/European snaths have them.
The logic of the upward (and at the same time slightly forward) pointing grips will be apparent to anyone who actually tries out the two options, side by side…
In any case, I think that the folks in the UK (using the Swiss made snath version sold by the Scythe Shop along with the cradle made by Steve Tomlin), as well as all those buying their “grain scythes” from Scythe Supply and Botan Anderson (mystic prairie) will end up working a lot harder for their bread than is necessary…"

(Source:  Photos and quoted text from Peter Vido, used with permission.)