bridges (18) campsite (25) cartoons (15) centenary (3) discussion (5) experimental (49) gadgets (23) gateways (11) lashings (21) models (9) raft (81) resources (26) sculpture (15) software (22) techniques (41) towers (42) trebuchets (5) treehouses (17) tutorial (9)

February 9, 2007

Loosening lashings: using a marlinspike


A Marlinspike is a pointed metal tool that is used for splicing ropes and untying knots. The marlinspike in the photograph is meant for untying lashings. It is made from mild steel round bar, with one end sharpened and the other hammered flat.

Typically, a marlinspike is necessary if lashings have been exposed to water and have swollen. The basic principle is to use it to open up a space in the hitches that end the lashing.
In this case, pushing the marlinspike in, and forcing it upwards makes space for the running end of the clove hitch to move- it's no longer being held by the crossing part of the hitch. The action used is to push the point in carefully, making sure not to damage the rope (the flat end of the tool can be useful to seperate two turns that lie very close together). Once the point is firmly pushed in, pushing the back end of the tool downwards twists the hitch backwards, and the running end normally comes loose. It can take a fair amount of force to untie: it's not unusual for our troop to bend marlinspikes while stripping a raft.



If a clove hitch is locked especially tight, twisting the free end of the rope can help loosen it: if you twist the rope in the direction of the lay, it becomes slightly narrower. Using one hand, twist the rope tighter, and then use the other hand to operate the marlinspike.

Using a marlinspike like this, most lashings can be easily untied, even if wet. If you have tied constrictors and allowed them to get wet, another tool is more useful for removing them.


Post a Comment