LASHINGS
A lashing is an arrangement of rope used to secure two or more items together in a somewhat rigid manner. Lashings are most commonly applied to timber poles, and are commonly associated with the scouting movement and with sailors.
The structure of a lash is nearly the same with any type of lashing, which is to tie two or more poles or spars together to create a useful structure. These structures can range from a simple pole extension, a ladder, to a shelter frame. The lashes presented here can create any type of formation that you may need.
An important aspect of creating a lash is to ensure the proper dressing (as with any type of rope work) of the knots and wraps that are used. Failure to pay attention to this detail can result in a collapsing of the structure being made.
For tying a lash the thinner the line or rope the easier it is to weave the lashing. An excellent material for making a lash is paracord, however bailing twine will also work. These lines are fine for minimal load bearing lashes, but if you expect to deal with loads that exceed 150 pounds, then heavier material are required. Quarter inch nylon rope makes an excellent material for load bearing structures, with 3/8" being the maximum that you would want to use (the heavier the line or rope the harder it is to handle or tighten).
A tool, such as a Marlin Spike or Lashing Stick, is invaluable in assisting the tightening of the lashing. Start at the beginning of the lash and tighten each coil individually, working toward the finishing clove hitch. Repeat this step until all slack has been removed form the lashing. (Note: The only exception to this rule is the Tripod Lashing, this is because a little slack will make it easier to spread the legs. Any slack will disappear as the legs spread.) If a Marlin spike is not available then you can use any semi-pointed tool (a sharp point or edge can damage the line or rope) such as a flat blade screw driver, the handle of a pliers or even a stout piece of wood (oak, hickory, tamarack) that has been whittled to shape.
DIAGONAL LASHING
Diagonal lashing is a type of lashing used to bind spars or poles together, to prevent racking. It is usually applied to cross-bracing where the poles do not initially touch, but may by used on any poles that cross each other at a 45° to 90° angle. Large, semi-permanent structures may be built with a combination of square lashing, which is stronger, and diagonal lashing.
Bailing twine has sufficient strength for some lashing applications but rope should be used for joining larger poles and where supporting people sized weights.
Diagonal lashing steps:
Tie a timber hitch diagonally around both poles.
Start the wrapping turns on the opposite diagonal to the timber hitch, by pulling the rope tight so that the poles contact each other.
Take 3 to 4 wrapping turns; keep the wrapping turns parallel; pull each wrapping turn tight. NOTE: If the wrapping turns are allowed to cross, the increased friction between the strands of the rope will make it difficult to tighten the wrapping turns.
Start the second set of wrapping turns by going past and around the vertical pole. NOTE: Going around the pole the rope allows the direction of the rope to be changed without crossing the first set of wrapping diagonally.
Take 3 to 4 wrapping turns; be sure to keep the wrapping turns parallel; pull each wrapping turn tight.
Start the frapping turns by going past and around one of the poles. NOTE: Going around the pole with the rope allows the direction of the rope to be changed without crossing the wrapping turns diagonally.
Take 2 to 3 frapping turns; keep the frapping turns parallel. Be sure to pull each turn tight.
End the lashing with a clove hitch. Take the first half hitch of the clove hitch by going past and then around one of the poles. Lock the half hitch tight against the lashing by working it tight.
Take a second half hitch around the pole.
Work the second half hitch tight against the first half hitch so that the clove hitch is locked against the lashing.
NOTE: If very smooth rope is used, the lashing can be made more secure by adding a third or fourth half hitch to the clove hitch.
A lashing stick can be used to safely tighten the joint. Strength will be improved if the first turn is 90° to the timber hitch and if care is taken to lay the rope turns parallel with no crossings.
Top of Page
ROUND LASHING
The round lashing is a type of lashing also known as vertical lashing. This lash ties two spars at a straight angle where the spars are clean and of equal diameter; if not you should use a sheer lashing or when security of the lashing is vital.
Round lashing steps:
- Position the poles beside each other and tie them together with a clove hitch around both poles.
- Round lashings bind two poles side by side:
- Position the poles beside each other and tie them together with a clove hitch around both poles.
- Make seven or eight very tight, neat wraps around the poles.
- Finish the lashing with another clove hitch around both poles.
There are no fraps in a round lashing. The wraps must do all the work, so pull them as tight as you can. Make a second round lashing father along the poles (a minimum of 6" should be allowed for) to keep them from twisting out of line.
When very smooth synthetic rope or very smooth poles are used, the round lashing can be made more secure by adding several additional half hitches to each of the clove hitches.
Top of Page
SHEAR LASHING
Use the shear lashing to bind together poles that cross each other at an angle between 0° and 45°, or where a flexible joint between the poles is needed, such as in a set of shear legs for an A-frame. Lay the poles alongside each other so that their bottom ends are even.
Shear lashing steps:
Tie a clove hitch around one pole.
Add five or six snug wrapping turns by weaving the rope back and forth around the poles.
Then take two frapping turns between the two poles; pull each frap tight.
End with a clove hitch worked tight against the lashing on the second pole.
Spread the ends of the poles to form the angle you need.
Top of Page
SQUARE LASHING
Square lashing is a type of lashing knot used to bind poles together. Large structures can be built with a combination of square and diagonal lashing, with square lashing generally used on load bearing members and diagonal lashing usually applied to cross bracing. If any gap exists between the poles then diagonal lashing should be used.
Square lashing steps:
Attach the rope to the first spar with a clove hitch.
Twist the loose end from the clove hitch around the rope and then wrap the rope around the two spars as shown.
When you start the second time around, guide the rope to the inside of the existing wraps on the first spar.
On the second spar guide the rope to the outside of the existing wraps.
Continue wrapping the rope around the spars following the "inside - outside" sequence.
Once you have enough wraps to give you the strength you need for the project, guide the rope horizontally between the two spars. This is called frapping. Pull the frapping as tight as possible and then add another turn. (If lighter rope is used 4 or 5 turns may be required.)
Finish the frapping by tying a half hitch. Wiggle the rope back and forth to ensure the hitch is in as tight as possible to the frapping.
Add another half hitch to finish the job!
Note: Most knotting books call for a clove hitch to finish a square lashing. By tying 2 half hitches you in fact have tied the required clove hitch.
The previous pictures showed the half hitches rather loose. In reality they must be pulled in tight to ensure the lashing does not loosen.
Why the Inside Outside rule!
If you do not pay attention to how you lay the ropes you will generally end up simply going to the outside. When you do that, the frapping will only catch the outer wrap and the lashing will loosen quickly.
Top of Page
TRIPOD LASHING
A close relative of the shear lashing, a tripod lashing is the lashing to use for making a tripod or for joining together the first three poles of a tepee.
Tripod lashing steps:
Laying three poles alongside each other so that their bottom ends are even.
Tie a clove hitch around one outside pole.
Add five or six snug wrapping turns by weaving the rope back and forth around the pole.
Then take two frapping turns between the first two poles; pull each frap tight.
Next, add two frapping turns between the second and third poles; pull each frap tight.
End with a clove hitch working tight against the lashing on the third pole.
Set up the tripod so that the two outside legs cross each other underneath the lashing.
Top of Page