Flax and Hemp Fiber (Processing and Spinning) an Introduction and How to guide by Kataryna Tkach
Written by Kataryna Tkach   
Wednesday, 06 October 2010 23:20

(note edited October 21,2010 for spelling/grammar errors)

Processing and spinning vegetable fibers is very different then working with animal fibers. Even the processing techniques for different types of fibers can vary widely. In some cases you are taking fiber off the leaves (Sisal), in others you are taking it off the seeds of the plant in the form of bolls (Cotton). For flax, hemp, and nettle you are taking the fiber from the outer section of the stem, called the bast. These fibers are called bast fibers.

 

 Bast fibers share similar characteristics – they are often quite long and durable. They all require retting (microbial or chemical digestion) to separate the fiber from both the core (center woody section, called hurd once it’s separated from the plant) and the epidermis (the skin) of the plant.

 As a fiber plant ages the fibers get thicker walls and stick together more securely – so fiber from the base of the plant is more coarse (after processing it by hand) then the fiber from near the top of the plant.

Plant

In some cases, such as flax, this difference isn’t very noticeable; but in cases where the plant is much larger, such as hemp, it is quite noticeable.

 

When bast plants are grown for fiber they are cut down before going to seed and retted. However, with both flax and hemp, a section of the crop would typically be left to produce seed for both the next year and sometimes (if an oil variety was not also grown in the same area) to produce oil from the seeds.

Retting is the process of allowing microbes, or in the modern day - chemicals to break the fibers away from the stalk of the plant. There are a number of ways that one can ret fiber plants – pond, stream, dew, and snow retting are the non-modern (non chemical) methods used most often.

 In pond retting the plants are cut and placed into a shallow pool of water until they are soft and the fiber comes away from the core easily. The time it takes is a couple days to a couple weeks and depends on the temperature of the pond and the type of microbes in the pond. This produces a grey colour to the fiber and is not as desirable because the retting is not as uniform – some fiber is over retted and some under retted.

Clean_flax

The above picture is pond retted flax.

 Stream retting is where you place the plants in flowing water for a couple of weeks. This produces a more uniformly retted fiber, and the colour is a yellow grey. The quality of the fiber you get from stream retting is average.

 Dew retting is allowing the cut fiber to sit in the fields allowing the dew to collect on it for a month or more. It can not be adequately done in a dry climate or to close to the onset of winter – so in Central Alberta, where I live, it is very rare to get conditions where this is possible to attempt. Dew retting produces the highest quality fibers.

For hemp, one more process exists, that of snow retting. For this you cut down your plants and collect them so that they do not start retting, once the snow falls and covers the ground you place a tarp or a wooden board out with the hemp stalks on top of it. Then let the snow cover the hemp for the winter. Allow the hemp to thaw in the spring but do not allow it to contact the ground or it will start dew retting. Snow retted hemp produces very fine bright golden or white fiber.

Clean_hemp_fibre_ready_to_be_spun

The above phote is snow retted hemp.

 A side not about the hemp: I work in a research facility that studies fiber hemp. Hemp is Cannabis, the same plant that people use to get high. Hemp varieties grown for fiber in Canada are ones which have little to no THC (the chemical in cannabis that gets people high). You’d typically have to smoke a whole field to get high (and would die of smoke inhalation before you even got a buzz). However, the regulations are such that the stalks we work with can not be removed from the facility – so those who have helped me process the fiber have come with me onto the site and processed the fiber under my supervision.

 

Once you have retted fiber bundles you need to dress them – that is to break, scutch, and heckle the fiber. A flax break looks like the following schematic is typically wooden, and works somewhat like a large dull wooden paper cutter. I have no pictures of the one we made and then destroyed trying to process hemp stalks with.

Flax_break

 

You can find a number of on-line pictures of breaks with a variety of configurations.

 As I mentioned the break we tried to use on our snow retted hemp broke. The pin connecting the top of the break to the bottom split because of the heaviness of the Hemp stalks. We placed too many stalks between the parts and I pushed down too heavily. We eventually took the arm off the break and used it by sliding it under another grooved piece of wood clamped to a metal table. This was a Kludge but it worked for the few days we had to process the fiber. For the very large hemp stalks we found it easier to place the stalks between a couple canvas drop cloths and dance or jump on them.

 

The scale of difference between fiber hemp and flax is very apparent in the picture below

Comparison_of_fibre_hemp_and_flax_stalks

As you can see, based on the size of the plants, the type of break used for bundles of flax will not last as long when processing hemp.

 

Hemp fiber can also be hand stripped if necessary, and holding the fiber so it slides between your first two fingers as you hold the stalk in the palm of your hand produces an angle that allows you to strip the length easily and quickly. This gives an advantage of not having to scutch the fiber, though you still must heckle it.

Two_bundles_hemp_fibre_broken_and_cleaned_

The above picture is of broken hemp ready to be scutched

 

There is a medieval mural that is listed as showing ladies preparing flax for spinning  

“1320 CYCLE SHOWING TEXTILE PREPARATION TECHNIQUES INVOLVING FLAX AND SILK FOR HOUSE WIFES AND YOUNG MAIDENS

A slightly faded wall painting from 1320 of flax and silk preparation/production (?)

 

1320 Zyklus mit Darstellung der Flachs- und Seidenverarbeitung, ausgefuhrt von Frauen und jungen Madchen
Bodensee?
Zyklus, aktuelle Funktion: Museum, Wandmalerei, Freskomalerei
Standort: Konstanz, Kanonikerhaus, Haus zur Kunkel, 2. Obergeschoss

http://www.bildindex.de/bilder/zi1800_0105a.jpg

From http://www.drakt.org/Medieval.html and also found on the medieval and renaissance material culture page (http://www.larsdatter.com/spinning.htm)

 This picture http://www.bildindex.de/bilder/zi1800_0073a.jpg shows the position you would sit in and how you hold your hands when you are hand processing hemp. The fiber stalks shown in the picture seem too large to be flax and to me resemble hemp stalks. Flax stalks are too thin to hand process in the same manner.

 

 Scutching is the process of removing the hurd remaining in the fiber after it has been broken. This is done with a wooden scutching knife, see the second panel of for a picture (same link as above) - http://www.bildindex.de/bilder/zi1800_0073a.jpg. To scutch fibers you hang them and then scrape and beat the knife down the length of the fiber, an iron scraper can also be used – or something like a metal dog comb. Scutching produces lots of hurd (woody fibers, also called shive in flax) and tow (small coarse fibers which grow horizontally rather then vertically in the stem). I save both for making a liquid for spinning the fiber.

Cleaning_fibre

The above picture is of me scutching hemp with an iron scraper. (You can also see the drop spindle I used for spinning the ball of flax (pictured below) in the upper left hand corner

Once you’ve scutched the fiber you need to hackle it in order to divide the fibers and remove the remaining epidermis. If you don't your spun material will be coarse and the excess bits of epidermis can cut your fingers and leave slivers. Hackles (or hatchel or hetchel) are basically beds of nails first 4 per inch then 12, 24, 48 and finally 80 nails per inch used to process finer and finer fibers. From the same medieval mural discussed above here is a picture of a lady using a fine hackling board

http://www.bildindex.de/bilder/zi1800_0075a.jpg

The tow that comes off during hackling can be carded and spun like wool to produce a coarse thread typically used for rope. I currently do not have nail beds of 48 or 80 nails per inch and have not been able to hand process fine thread suitable for weaving. What I have processed is string like.

 

Once you have your fiber you are going to want to spin it (of course). All plant fibers are quite slick, and unlike wool; which has lanolin that allows it to bind to itself, something has to be added to spin the bast fibers. Water will cause the fibers to be a little sticky – but it’s not the best.

The enzymes in spit dissolve some of the cell wall and allow flax, hemp, and nettle fibers to stick to each other. The other solution that you can use is to boil some of the tow, and hurd along with some of the seed (or oil) from the plant in question and then strain the liquid out. This liquid can be used instead of spit to make the fiber sticky – the liquid contains bits of the glue that holds the cell wall together naturally.

The folk tale of the three spinners (collected by Giambattista Basile 1566-1632); one with a swollen thumb from drawing the thread, one with a swollen lip from wetting the thread and one with a swollen foot from treading the wheel, is thought to have been a description of women who processed flax. The lip from allowing the fiber to pass along the lower lip as it was being drop spun which caused small cuts – many of which could become infected from improperly cleaned fiber (the retting process giving the fiber a higher bacterial load), the same with the thumb. The swollen foot is theorized to be from sitting so much. This also suggests that spit was the liquid of choice in the middle ages for spinning plant fibers.  

Drop spinning using a relatively short draw and keeping your fingers wet with spit, or the tow mix seems to be the key to producing strong and fine fibers.

Flax_spun_with_a_drop_spindle

 My drop spun flax

 

A couple of notes before I leave off this entry:

  • Oil varieties of hemp and flax, and medicinal varieties of hemp were already seperate crops by the 1500’s. Although encountering different varieties tended to do with what each plant was being used for in an area (though the fiber variety and the oil variety of hemp was grown as separate crops in some areas of China and the near east). Fiber hemp is historically the most common form of hemp grown in Europe during the middle ages and renaissance. I would caution against trying to grow oil or medicinal varieties of either crop then spinning the fiber you get from them – the plants (and hence fiber) are generally shorter and the fiber breaks much more easily.

 

  • The hemp I processed for this is Silesia, a Polish cultivar that is a very good fiber producer and gives lots of strong fine fibres. It was developed in Poland by
    Institute of Natural Fibres and Medicinal Plants
    ul. Wojska Polskiego 71b
    PL 60 630 Poznan, Poland
    tel.: (+48 61) 84 55 800, (+48 61) 84 800 61
    fax.: (+48 61) 841 78 30

    As far as I can determine this cultivar  was developed in the 60's from fiber hemp landraces grown in Silesia (a province of Poland).... so this is likely very close to the sort of hemp that would have been used in that area in the middle ages; but, as they haven't released information on the lines crossed to get the cultivar or noted that it came from a landrace, this is only a guess.

 

  • I do not have details about the flax cultivar; it was given to me by Countess Elisabeth de Rossignol who was teaching a class on flax processing. She had grown it for the fiber.

 

  • I'd like to thank Dragoslava Vladislasa doch, and Kelly for helping me process the fiber bundles over the course of a few weekends.

 

If you have any questions feel free to contact me via the SCA community page or via email at kataryna_dragonweaver at yahoo dot com (replace the at with an "@" the dot with a "." and remove the spaces)

Kataryna Tkach.

(My next A&S entry (probably next month) will either be details on one of my crazy kiln projects - building a salt kiln, building a pit kiln, or building a wood oven; or maybe something about the history of decorating eggs. If folks who read this have a preference drop me a comment.)