John Sweet – SCOUT PIONEERING

The Somewhat Ambiguous Shear Lashing

VIEW VIDEO: How to Tie a Shear Lashing

Scouts Lash the Tops of Their Sheer Legs with a Two-Spar Shear Lashing to Begin Their Single A-Frame Bridges — Scouts Lash the Tops of Their Shear Legs with a SHEAR LASHING to Begin Their Single A-Frame Bridge

DEFINITION: ambiguous |amˈbigyoōəs|adjective(of language) open to more than one interpretation; having a double meaning; unclear or inexact

Put the two timbers together and tie a clove hitch near the top of one. Bind timbers together by seven or eight turns. Make turns loose, one beside the other. Make two complete frapping turns around lashing turns between the timbers. Fasten securely with clove hitch around one timber. Open out the timbers. Note: Two shear lashings without frappings and with the clove hitch around both timbers are used to lash two timbers into one long one. — From the 1981 Printing of the Pioneering Merit Badge Pamphlet

One Thing is NOT Ambiguous! The shear lashing’s USE is quite clear. References to the lashing in John Thurman’s Pioneering books, in John Sweet’s Scout Pioneering, and the Lashing section in the Pioneering Merit Badge Pamphlets by Pioneering Legend Adolph Peschke all describe its fundamental use exactly the same way. Putting it neat like John Sweet: Use a sheer lashing “when two spars are to be opened out like scissors to make a pair of sheerlegs,” or right to the point like John Thurman in Pioneering Projects, the sheer lashing is “used for lashing together two parallel spars which will be opened out of the parallel to form sheer legs.”

What are sheer legs? Simply put: sheer legs are two upright spars lashed together at the tips with the butt ends splayed apart to support some kind of weight. Most always, in Scout Pioneering we use sheer legs to form an A-Frame.

Ambiguous? Yes. Let’s start with ambiguous spelling! Most modern references to the lashing spell it s-h-e-a-r. Yet, the much respected and revered John Thurman was emphatic that the correct spelling was s-h-e-e-r!

Terminology. In John Sweet’s book, sheer lashing has two different forms each with the same name. When two spars are lashed together for strength, or lap-jointed to extend their length a sheer lashing is used BUT with the clove hitches tied around both spars and without any frapping turns. He still calls it a sheer lashing, but of course this is commonly known as a round lashing! John Thurman refers to a true round lashing as the Sheer Lashing Mark II and the lashing used to make sheer legs as the Sheer Lashing Mark I.

Let’s take this opportunity to further clarify two lashing designations that keep popping up. A SHEAR Lashing is used to make shear legs. A ROUND Lashing is used to attach one pole to another in the same direction as in extending the overall length of shorter poles. (It can also be used to bind more than one pole together to make a stronger pole.) SHEAR Lashings incorporate frapping turns. ROUND Lashings do not! Along these lines, the West Country Shear Lashing should be called the West Country Round Lashing, and rightfully so!

Nowhere is this stated more clearly than in Gerald Finley’s book, Rope Works: “West Country Round Lashing is also called West Country Shear Lashing, but this name contributes to the confusion caused by lumping shear and round lashings together. West Country Round Lashing is used to form a rigid joint between two parallel poles; it does not form the flexible joint of a shear lashing and it has no frapping turns.”

Two-Spar Shear Lashing. To add to the possible confusion, Adolph Peschke calls what John Thurman refers to as the Sheer Lashing Mark I (which is in actuality THE shear lashing) the Two-Spar Shear Lashing. This name can also be related to the tying of a Tripod Lashing With Plain Turns, wherein the procedure is exactly like the Two-Spar Shear Lashing but with three spars. It follows that it’s easy to dub this tried and true form of tripod lashing (just like the Two-Spar Shear Lashing) the THREE-Spar Shear Lashing. The Two-Spar Shear Lashing is used to make an A-Frame, and the Three- Spar Shear Lashing is used to make a simple tripod.

Ambiguity in Tying the Lashing. Though the formation is the same: clove hitch around one spar, six to eight wraps, two fraps, finish with clove hitch around one spar, there are varied approaches to actually tying the shear lashing. These discrepancies all hinge on… the hinge. (Pun intended.) The spars have to pivot in order to spread out the desired distance. How can this be accomplished so the lashing is tight but not so tight that when spreading the legs into position, the legs and lashing rope resist the strain to the point that something breaks? The tighter the wraps, and the more wrapping turns you take, the stiffer the lashing will be.

One view is to make the wraps and fraps on the loose side, concluding they’ll tighten when the legs are spread.
Another view is to place a small block of wood between the spars to yield adequate room for the frapping turns.
Another view is to make the wraps moderately tight and then before frapping, spread the legs a bit to allow room for the frapping turns, being careful not to close the spars on the lasher’s fingers!
Finally, another view is to complete the wraps, then spread the legs to the desired width, and then take tight frapping turns.

Whatever works well will also depend on the diameter of the spars, how straight they are, and indeed on the structure itself.

Open out the Timbers. NOTE: Two shear lashings without frappings and with a clove hitch around both timbers are used to lash two timbers into one long one. — The NOTE is a perfect description of what is termed the “Round Lashing!”

Favorite Pioneering Knots: Scaffold Hitch

The scaffold hitch is a superb knot, and in pioneering easily serves a dual purpose.

Primary Role: This is a seriously good knot to use in the construction of a pioneering project bosun’s chair (boatswain’s chair) for a small, straight aerial runway adaptation or a project where a seat is needed to suspend a Scout from a rope swing. As John Sweet points out in Scout Pioneering, it’s a good idea to cut notches about 4 inches from the ends of the board to give the rope something to bite into.

Link to: Larger Image — Bundles of 4′ Spars

Second Role: Many different knots can be used for fastening bundles of sticks or poles together, but when it comes to bundling up of 3 to 4-inch ladder rungs, platform spars, and walkway cross spars, the scaffold hitch provides superior clinching power, which is what is needed to keep the bundles tight. (Unless your using screen spline, it’s unparalleled for bundling Scout staves!)

Working your way towards the end of the board, make three wraps around the board. Take hold of the 1st wrap and lay it over the 2nd, then take hold of the 2nd wrap and carry it over both the 1st and 2nd wraps and over and under the board.. Pull both ends of the rope tight and position the rope ends so the board will be held in place. — Tying the Scaffold Hitch: PRIMARY ROLE

With the middle of the rope, working your way towards the end of the bundle, wrap the rope three times around the bundle. / Take hold of the 1st wrap and lay it over the 2nd. / Take hold of the 2nd wrap and carry it over both the 1st and 2nd wraps and around the bundle. / (Pull both ends of the rope tight and wrap the remaining length of both ends around the bundle. / Secure with a square knot.) — Using the Scaffold Hitch to Bundle Poles.

Favorite Pioneering Knots: Timber Hitch

VIEW VIDEO: How to Tie a Timber Hitch

The following text is by Adolph E. Peschke as presented in the 1998 printing of the 1993 edition of the Pioneering Merit Badge Pamphlet in the Lashing Section describing the traditional diagonal lashing…

When putting crossed braces on a structure to keep it from racking (as used when making a trestle), the most important lashing is the diagonal lashing where the spars cross.

When the cross spars are properly assembled on the trestle, they will be standing apart where they cross. That is, there will be a few inches of space between the spars where they cross at the center of the X. To pull them tightly together, a timber hitch is used to start the lashing. As the timber hitch is pulled tight, the spars are sprung together.

and in the Basic Knots Section describing the timber hitch:

The timber hitch is a knot that can be tied quickly. As strain is put on the rope, the knot gets tighter, yet it remains easy to untie.

To tie a timber hitch, first wrap the running end around the timber log or spar. Then loop the running end around the standing part of the rope, continuing to wrap the running end around itself a few more times. This will form a hitch that will tighten on the timber as the rope is pulled. After the timber is dragged or hoisted into position, the timber hitch is easy to untie.

When pulling or lifting a timber, log, or spar, throw a hitch around it at the end that is being pulled or lifted. — Killick Hitch

A note about this final half hitch: when using the timber hitch to lift or pull an object, that added half hitch combined with the timber hitch forms what has been referred to as a Killick Hitch. John Sweet in Scout Pioneering suggests this combination when making a lobstick to throw a line over a branch. The Killick Hitch is also known as a Kelleg Hitch. The timber hitch is most always exampled as the first step in tying the combination.