Sodium carbonate (washing soda) can be easily made from sodium bicarbonate (baking soda) by heating in the oven, but I've decided to get some off the eBay!
Now just gotta wait approx. 1 week before it arrives.
Update #1 / 4th Sept 2013[]
Got it finally home - one bottle as on the picture and the "refill" plastic bag with another portion. Let's cook! ;)
Update #2 / 5th Sept 2013[]
2 twines skeined - left 100% cotton, right 70% bamboo and 30% cotton
Closeup of twines
Boiling twines for an hour (or a bit more)
Cooling down to approx. 150F/65C
Soda washing for an hour or so
Washed in the clean water and hung to dry
Close-up of the bamboo twine
Close-up of the bamboo twine
Close-up of the cotton twine
Dried bamboo yarn
Dried cotton yarn
Dried cotton (left) and bamboo (right) yarns
Dried cotton (left) and bamboo (right) yarns
Dried cotton (left) and bamboo (right) yarns
Comparison. Bamboo, cotton, cotton piping cord with different diameter. Soda washed ones are to the left of the raw ones to the right, paired.
Comparison. Bamboo, cotton, cotton piping cord with different diameter. Soda washed ones are to the left of the raw ones to the right, paired.
Comparison. Bamboo, cotton, cotton piping cord with different diameter. Soda washed ones are to the left of the raw ones to the right, paired.