Manufacture

Sourcing raw materials

To produce a high-quality yarn, excellent raw materials are required. Each raw material that we use is tested by our own quality management system. This includes the following tests:

  • •Comb top and fibre quality control 
  • Checking production at source
  • •Verification of all raw materials in accordance with Ökotex  Testex® 1st. class 100 Standard   

On arrival, comb top samples are taken to the company laboratory and tested for fibre length, shine, knots and extraneous fibres and only then allocated to production. In order to guarantee the same yarn quality over a longer period of time, the different batches are combined into one batch for spinning. 

 

From sliver to the yarn

We produce all of our yarns on site in our production facility in Gersau and at least 60% of the production costs are in Switzerland. This means that all of our yarns meet the conditions of  "Swissness" and are officially allowed display the Swiss cross. Another advantage of on-site production is that we can keep to and check that we are meeting our ethical and environmental protection requirements, making adjustments accordingly whenever necessary (see Swiss Mountain Silk)

  • In pre-manufacture, we mix together the different comb tops. For pure silk, we mix different supplier batches to ensure consistent quality. For the blended yarn we mix the different raw materials with the appropriate proportion of silk. For this purpose, up to 14 rotations are needed in the gill box in order to mix the strips as homogeneously as possible. Then, on the pre-spinning machine (flyer), these strips are stretched to the right proportion in order to obtain the ideal roving for the spinning process.

    Flyer
    Production of Rowing yarn on a Schlumberger flyer

     

  • Ring pin machines with long staple drafting units are available for this purpose, some of which are equipped with a Lutenstop device and a doffer. As we produce 2 nm to 300 nm fine yarns (nm = number of meters per gram), corresponding different machine types are used. For our finest yarn, the roving is spun 50 times and over 1200 rotations per metre into a silk thread. The spinning cops are treated with saturated steam to stabilise the rotation in the vacuum damper before the spun yarn is wound onto cones by fully automatic winding machines. During winding, each meter of the yarn is monitored by an electronic probe. Defects such as thick and thin spots, knots and pimples, nm irregularity and extraneous fibres are detected and cut out of the thread and cleaned using the latest electronic yarn cleaners. The ends of the threads are spliced immediately as the fibres are compressed with compressed air so that the strength of the compound reaches 90% and becomes almost invisible. This process guarantees a consistent yarn quality which meets the high standards for further processing. 

    Spinnen
    Spinning on ring spinning machine from Sauerer Zinser

     

  • Two or more individual threads are intertwined. After the yarn has acquired a Z direction pattern during spinning, the two yarns together form an S-twine. The twine makes the yarn more tear and abrasion resistant. We work with the two-stage twining process. Firstly the threads are double folded and pre-twined, and in the second stage the final rotation is twined. Because of the long time it takes, the yarn rotates protected from dirt in a so-called pot. After twining, the yarn is again steamed for stabilisation and subsequently singed. 

    Zwirnen
    Twisting by two-step method

     

  • Our use of singeing machines is based on an old principle. While we built the first sewing machines especially for silk, a machine factory later further developed and built the machines. Our mechanics then adapted the sewing machines to our needs. By singeing the yarn, the protruding fibres are burned away; Thereby the yarn becomes smoother with a beautiful silk shine.

    Sengmaschine
    Singeing with electric burner

     

  • Through a revised electronic check, the yarn acquires the finish that customers desire (cones and threads). If desired, the thread can be delivered with a paraffin application. Our products are used in weaving (clothing, furniture, paraments), knitting (sweaters, underwear, socks, tights, etc.), in carpet production, hand knitting, hand weaving, hand embroidery and sewing threads. Our customers are located in Switzerland, in many EU countries as well as in the USA, Canada and other countries worldwide. Since 2007, all of our yarns have been marketed under the brand name of  Swiss Mountains Silk 

    Produktion von Strangen
    Production de écheveaux

     

In pre-manufacture, we mix together the different comb tops. For pure silk, we mix different supplier batches to ensure consistent quality. For the blended yarn we mix the different raw materials with the appropriate proportion of silk. For this purpose, up to 14 rotations are needed in the gill box in order to mix the strips as homogeneously as possible. Then, on the pre-spinning machine (flyer), these strips are stretched to the right proportion in order to obtain the ideal roving for the spinning process.

Flyer
Production of Rowing yarn on a Schlumberger flyer

 

Ring pin machines with long staple drafting units are available for this purpose, some of which are equipped with a Lutenstop device and a doffer. As we produce 2 nm to 300 nm fine yarns (nm = number of meters per gram), corresponding different machine types are used. For our finest yarn, the roving is spun 50 times and over 1200 rotations per metre into a silk thread. The spinning cops are treated with saturated steam to stabilise the rotation in the vacuum damper before the spun yarn is wound onto cones by fully automatic winding machines. During winding, each meter of the yarn is monitored by an electronic probe. Defects such as thick and thin spots, knots and pimples, nm irregularity and extraneous fibres are detected and cut out of the thread and cleaned using the latest electronic yarn cleaners. The ends of the threads are spliced immediately as the fibres are compressed with compressed air so that the strength of the compound reaches 90% and becomes almost invisible. This process guarantees a consistent yarn quality which meets the high standards for further processing. 

Spinnen
Spinning on ring spinning machine from Sauerer Zinser

 

Two or more individual threads are intertwined. After the yarn has acquired a Z direction pattern during spinning, the two yarns together form an S-twine. The twine makes the yarn more tear and abrasion resistant. We work with the two-stage twining process. Firstly the threads are double folded and pre-twined, and in the second stage the final rotation is twined. Because of the long time it takes, the yarn rotates protected from dirt in a so-called pot. After twining, the yarn is again steamed for stabilisation and subsequently singed. 

Zwirnen
Twisting by two-step method

 

Our use of singeing machines is based on an old principle. While we built the first sewing machines especially for silk, a machine factory later further developed and built the machines. Our mechanics then adapted the sewing machines to our needs. By singeing the yarn, the protruding fibres are burned away; Thereby the yarn becomes smoother with a beautiful silk shine.

Sengmaschine
Singeing with electric burner

 

Through a revised electronic check, the yarn acquires the finish that customers desire (cones and threads). If desired, the thread can be delivered with a paraffin application. Our products are used in weaving (clothing, furniture, paraments), knitting (sweaters, underwear, socks, tights, etc.), in carpet production, hand knitting, hand weaving, hand embroidery and sewing threads. Our customers are located in Switzerland, in many EU countries as well as in the USA, Canada and other countries worldwide. Since 2007, all of our yarns have been marketed under the brand name of  Swiss Mountains Silk 

Produktion von Strangen
Production de écheveaux