What you should consider when using pre-dyed jute rope
Because jute is hydrophilic it will readily absorb liquid. Jute rope unsupported (i.e. without tension) will shrink in length ~6% and fatten ~20% when wet. If allowed to dry without longitudinal tension applied, it will settle ~4%, but the diameter will not return to the original dry length.
Notably, after drying unsupported with longitudinal tension, the rope will feel light, and its integrity for application may be compromised.
If one takes a pre–dyed rope, it is wise to cut off a short piece, unravel and count the total number of yarns. The best jute rope manufacturers will generally use either 14/1 or 15/1 yarns (Jute Count/Ply). Depending upon final twist dynamics balanced ropes use equal numbers of yarns per strand, and this will result in the following total number of yarns:
- ø6.0mm = 33 yarns
- ø5.5mm = 30 yarns
- ø5.0mm = 27 yarns
- ø4.5mm = 24 yarns
Therefore, e.g. if a pre–dyed rope feels light yet measures ø6mm in diameter but only has 27 yarns, it is a ø5.0mm rope that has been dyed and dried unsupported, and users should be aware of load limitations in application.
Natural drying under tension assists wet rope to return to original dimensions. Longitudinal loads of the following minimum weights in grams per meter should be applied:
- ø6.0mm = 980g
- ø5.5mm = 900g
- ø5.0mm = 800g
- ø4.5mm = 750g