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Lashing INFORMATION

The following text and some of the drawings are by Adolph E. Peschke as presented in the 1998 printing of the 1993 edition of the Pioneering Merit Badge Pamphlet:

We could imagine the first lashing made by man was wrapping a few strips of bark around a stone to hold it to a tree branch to make an ax to hunt and build with. Even today with all our modern ways to hold things together, it is still fascinating to lash sticks or spars together to make a camp gadget or useful structure.

There are still areas in the world where lashing spars (or bamboo poles) is the basic means of building structures. In Scouting, we use the same methods but have replaced strips of bark and vines with natural and synthetic fiber ropes.

The best choice of rope to use for lashing the type of pioneering projects (shown in this pamphlet) is pure manila rope. Therefore, all references to rope used for lashing in this section refer to manila rope.

Yet, sometimes we are faced with a problem—we have to use what is available and economical to get the job done. When making camp gadgets for temporary use, you could use lesser quality, less expensive rope or even binder twine for small projects.

SQUARE LASHINGS ***

The basic type of lashing for most projects is some form of a square lashing. This lashing is used to join two spars together, usually at a right angle, but not always. For example, square lashings are used when building a trestle to join the ledger and header to the legs at right angles. But it is also used to hold the ends of the X bracing to the legs at an angle. (Refer to “Making a Trestle.”)

In this section, three different square lashings are shown: (1) the Traditional Square Lashing, (2) the Modified Square Lashing, and (3) the Japanese Mark II. All three types of square lashings accomplish the same thing by making three wraps and two frapping turns around the spars being held together.

The only difference between these three different square lashings is the type of knot that is used to start and complete the lashing. You may learn that one of these knots is easier to tie, if so, you can stick with the one you are most comfortable with.

In addition to square lashings, you will most likely need to know how to make a diagonal and shear lashings. Some methods of making these types are also shown later in this section.

LASHING TERMS

No matter what kind of lashing you’re making, there are two basic terms you should be familiar with: wraps and fraps. The basic difference between the two terms is that a wrap is made around the spars, while a frap is made around the rope itself.

Wrap. A wrap is a turn made around the two spars to hold the spars tightly together. Usually, three wraps are made to form a Square Lashing. Some other lashings require more wraps.

Frap. A frap is a turn made between the spars. It goes around the wraps to pull the wraps tighter. Usually two frapping turns are made on a lashing.

Good lashings are not made in a hurry. Each wrap must be made with a strain on the rope. Frapping turns should be pulled up as tightly as possible before the final knot is tied.

ROPE LENGTH

When you set out to make a lashing, the size and length of the rope you need are among the first questions you have to answer. To determine the length of rope needed for a lashing, add the diameters (in inches) of the two spars at the point the lashing is being made. If one spar is 2-1/2 inches in diameter and the other is 3-1/2 inches in diameter, the total equals 6 inches. Multiply by 3 feet to get the length of the rope needed for lashing.

If you use a rope that is too short to make three wraps and two fraps for a lashing, you should add (Splice or join with a Square Knot) a length of rope to complete the lashing with three full wraps and two fraps. For safety, don’t leave the lashing short.

If you find you have extra rope, make more wraps or fraps to use up the rope to avoid cutting the rope or leaving long loose ends hanging out.

ROPE DIAMETER

In most cases, 1/4-inch diameter manila rope should take care of lashing two spars together as long as the combined diameter of both spars is 6″ or less. When the combined diameter is over 6 inches, use 3/8-inch diameter rope.

PIONEERING KIT

If your troop or camp puts together a pioneering kit, it should contain lashing ropes that are cut to standard lengths: 10, 15, 20, 30 and 50 feet.

Both ends of these lashing ropes should be properly whipped. It also helps to color-code the ends of all ropes with a bit of paint to denote each length. When storing ropes, make sure they are dry and properly coiled. Never “hank” ropes for storage. That is, don’t wrap them around your hand and elbow to form a coil. Tie each coil with a short piece of cord and store the coiled rope on pegs or in a ventilated storage box.*

TRADITIONAL SQUARE LASHING

Drawing Design from Rope Works by Gerald L. Findley http://www.ropeworks.biz/reader/squarlas.pdf
Drawing Design from Rope Works by Gerald L. Findley http://www.ropeworks.biz/reader/squarlas.pdf

In Scout Pioneering in the United States we most often see the square lashing started with a clove hitch. The clove hitch is tied on the vertical spar, just below where you want to join the crossing horizontal spar (see 1).

Using a clove hitch to start this lashing allows for two things. First, you can rest the crossing spar on the clove hitch to help support it as you begin the lashing while building your structure. Second, the clove hitch helps keep the structure from racking (twisting out of shape), causing the lashing to loosen as it is moved or hoisted into position.

After the clove hitch is tied, wrap the excess short end of the rope around the standing part of the rope (see 2). Hold the crossing spar up to the vertical spar and make three wraps around the spars using the long end (see 3, 4, and 5). Pull each wrap tight to hold the spars together. Make two frapping turns around the wraps (between the spars) to pull the wraps tight (see 6 and 7) and finish with another clove hitch on the horizontal spar (see 8 and 9).

One other point to make about the square lashing is that you shouldn’t be fooled by or limited by its name. Although two spars can be lashed together at 90° using a square lashing, it can also be used to lash two spars together at any angle. For example, a square lashing is used to lash the ends of two light spars to the uprights of a trestle to form the X bracing. A diagonal lashing is used at the center of the X to hold the crossed spars together.

MODIFIED SQUARE LASHING

The Modified Square Lashing was developed because of the difficulty usually experienced when tying a clove hitch to complete the traditional square lashing. The clove hitch that starts the lashing is easy enough to make, but tying a clove hitch at the end of the lashing is a different matter.

As shown in figure 104, the modified square lashing starts with a clove hitch. When tying the clove hitch, let the running end of the clove hitch extend about 12″. Also do not twist the short end around the standing part of the rope as in the traditional square lashing.

After tying the starting clove hitch, proceed as usual using the long end of the rope to make three wraps (see figure 105). Then make two frapping turns (see figure 106).

To complete the lashing, bring up the short end of the rope that extends from the clove hitch and tie a square knot (see figure 107). Bring the short end up in the opposite direction of the frapping turns.

As in the Traditional Square Lashing, there is some disadvantage in having to make the complete lashing using the one end of the rope.

Modified Square Lashing
Modified Square Lashing

JAPANESE MARK II SQUARE LASHING

This lashing is a straightforward approach to the task of lashing two spars together. (CLICK HERE FOR INFORMATION AND PROCEDURE.)

Square Lashing
Japanese Mark II Square Lashing Photographed Procedure

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. (Refer to the “Making a Trestle” section.)

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 (figure 1). As the timber hitch is pulled tight, the spars are sprung together. Next, three wraps are made in each direction across the X (figures 2 thru 5). After the wraps, make two frapping turns between the spars, pulling the wrapping turns tightly together and taking up any slack (figures 6 and 7). Finally, tie a clove hitch on one spar to complete the lashing (figures 8 thru 10). When this lashing is added to the cross braces, it helps keep the trestle from racking. Filipino Diagonal Lashing.

Diagonal Lashing Diagram
Diagonal Lashing Diagram

WEST COUNTRY ROUND LASHING 

The pattern you make with the rope for this lashing is the same as the one to make the whipping. The only difference is that this lashing is tied around two spars to hold them together.

To make this lashing, tie a series of half-knots (overhand knots) around the two spars (see figure 115). Tie one half-knot in front and the next half-knot in back (see figure 116). Make sure each half-knot is pulled up as tight as possible. After tying six to ten half-knots, finish off the lashing with a square knot (see figure 117). By using six to ten half-knots in this lashing, it makes it very strong and effective, but can be a little difficult to untie.

The West Country Round Lashing is used to tie two spars together to extend the overall length of the spars. When this is done, you should make two sets of lashings, not just one lashing. Make one lashing at each end of the overlapping spars.

West Country Shear Lashing Diagram
West Country Shear Lashing Diagram

TWO-SPAR SHEAR LASHING (Shear Lashing)

The main application for the Two-Spar Shear Lashing is when spar legs are to be spread apart to form an A-frame.

The Two-Spar Shear Lashing starts with a clove hitch on one spar (see figure 118). After making the clove hitch, wrap the excess part of the short running end around the standing part of the rope (see figure 119).

Two-Spar Shear Lashing Diagram
Two-Spar Shear Lashing Diagram (this drawing has been modified for the purpose of clarity)
Completed Shear Lashing Before the Spars have been Spread
Completed Shear Lashing Before the Spars have been Spread
Shear Lashing After Spreading the Shear Legs
Shear Lashing After Spreading the Shear Legs

Unlike square lashings, the shear lashing requires eight or ten wraps around the spars before making the frapping turns between the spars to pull the wraps tight (see figure 120). This lashing then ends with a clove hitch on the other spar (see figure 121).

If you’re making an A-frame, start the spars side by side and tie a clove hitch on one spar, about 1 foot from the top end of the spars depending on the project. Then you can take ten wrapping turns around the spars, making the wraps somewhat loose. The legs can then be spread to the required distance. This should put strain on the wraps.

With the legs apart, you can make the frapping turns around the wraps to pull them tight. Finally, complete the lashing by tying a clove hitch on the opposite spar.

The Somewhat Ambiguous Shear Lashing

STROP LASHING

In some pioneering situations all that’s needed is a few wraps with a rope, a light cord, or binder twine to hold two small spars or sticks together. Wrap the rope or cord around the spars a few times and finish with a Square Knot. This is called a strop lashing.

A strop lashing can be drawn down tight, or it can be made as a loose wrap so that it allows movement or acts as a hinge.

The strop lashing can have several simple applications at camp. For example, if you don’t want to dig a hole for the staff of your patrol flag, drive a tall stake in the ground. Then use a light cord or binder twine to make two strop lashings about 1 foot apart to hold the staff to the stake (see figure 122).

If your patrol just completed a signal tower and you want to show who did it, lash your patrol flag to the top of one of the legs with a strop lashing.

When you’re adding walkways to a bridge, they need to be joined to the trestle to form a single unit. The way to do that is to lash the two walkways to the transom at the center of the bridge with two or three strop lashings (see figure 123).

The ends of the walkways also need to be held to stakes. Use a strop lashing to hold the ends of the walkway to the stakes (see figure 124).

Strop Lashing
Strop Lashing

The Boy-Sized projects provided and designed by Adolph Peschke and featured in the older Pioneering Merit Badge Pamphlet (Single Lock BridgeSingle Trestle Bridge, A-Frame Bridge, Double A-Frame Monkey Bridge14′ Double Ladder Signal Towerdo not require the frequently employed tripod lashing, and hence it’s not included herein.

* An approach that is seen as a practical way to preserve and organize your lashing ropes is to coil ropes of the same length into manageable groupings, i.e. a large coil containing more than a single rope, and then tying up the grouping at one end with a 3-foot light cord.

** Round lashings are more frequently used to very effectively extend Scout staves or smaller diameter spars.

*** In a square lashing, the wraps and fraps form a square. In a diagonal lashing the wrapping turns cross the poles diagonally. Both lashings can be used to join two poles together that cross each other from 45º to 90º.  It’s the square lashing that is used most because there is more contact between the rope and the poles, and hence it is stronger. A diagonal lashing is used when there is a need to close a gap between two spars or when they spring apart, in other words, when we want to bind poles together where they cross each other but do not touch. This most commonly occurs when the ends of the spars are already lashed in place in a structure, as in forming the X-brace of an H-Trestle.

PDF FILE for: Lashing INFORMATION

Anchoring Pioneering Projects

The following text is by Adolph E. Peschke as presented in the 1998 printing of the 1993 edition of the Pioneering Merit Badge Pamphlet:

Building pioneering projects often requires some type of strong point for attaching a guyline for a tower or derrick. An anchor point might also be needed to anchor one or both ends of a monkey bridge.

Sometimes nature will provide a tree or rock in just the right location or you might be able to shift the location of the project to take advantage of a natural anchor.

STAKES

Pioneering Stakes

When nature does not provide a solution, anchors can be constructed using stout pioneering stakes.

Note: Under no conditions should tent pegs be used for pioneering stakes. They’re not long enough or strong enough to make a safe anchor.

Pioneering stakes should be made of hardwood, such as oak or hickory. The most common size of stake (for the projects shown in this pamphlet) is 2-1/2 inches in diameter and about 24 to 30 inches long (see figure 84). After cutting the stake to this size, cut a point on one end. Then bevel the top edge to prevent it from mushrooming or splitting when the stake is driven into the ground.

MALLET

Wooden Mallots
Wooden Mallets

When driving stakes into the ground, it’s best to use a wooden mallet. Using a metal sledge hammer or an ax head will damage the stake.

To make a wooden mallet, cut a 4-inch diameter piece of hardwood, such as hickory, elm, or sycamore, about 11 inches long (see figure 85). It should weigh about four pounds. Drill a 1-1/8-inch diameter hole to mount the handle. The handle can be made from a 24-inch length of hardwood (similar to making a stake). Use a knife or ax to round the end of the handle to fit the hole in the mallet head. Secure the handle in place with a wedge placed crosswise to the length of the head.

Buried Spar & Guyline Placement
Buried Spar & Guyline Placement

SOIL CONDITIONS

When driving the stake into the ground, drive it at about a 20° angle. Soil conditions can vary and will dictate how large and long a stake you need. If there will be a heavy strain on the anchor, you might need additional stakes as in the 3-2-1 configuration (shown in figure 89). After the stake is driven into the ground, keep your eye on it as strain is applied to see how it’s holding.

If ground conditions are unsuitable for even the largest stake you have, use a 4-inch diameter spar that’s buried 35 inches in the ground at a 30° angle and anchored in place with a stake (see figure 86).

GUYLINE

Always attach the guyline around the stake as close to the ground as you can get it. If the guyline is placed or slips higher on the stake, there will probably be enough leverage to pull the stake loose (See figure 87).

ANGLES FOR GUYLINES

Both the 3-2-1 anchor and the log-and-stake anchor should be positioned so that the guyline is at a 15° angle, or a maximum of 25°. To determine this, measure the height at the point where the guyline is attached. Double this distance to determine the minimum distance required between the base and the anchor. For example, if the guyline is attached 10′ up the pole, the anchor should be a minimum of 20′ from the base (see figure 88). If your line is long enough, it won’t hurt to place the anchor a few feet further out.

Angles for Guylines
Angles for Guylines and Guyline Length

3-2-1 ANCHOR

Strong Anchor for Pioneering Projects
Strong Anchor for Pioneering Projects

As the name implies, the 3-2-1 anchor is made by driving stakes in a series: three stakes, then two stakes, and then one stake to form the anchor (see figure 89). All six stakes are 30 inches long and are driven 18 inches into the ground at a 20° angle.

First drive in the set of three stakes. Next drive in the set of two stakes about 24 inches away from the first set. Then tie a rope from the top of the three-stake set to the bottom of the two stake set using at least two loops of 1/4-inch manila rope, or six to eight loops of binder twine. Then use a small stick to twist the rope tight in a tourniquet. After the rope is twisted tight, push the end of the stick in the ground to keep it from unwinding.

Finally, drive a single stake in the ground about 12 inches from the two-stake set. Once again, use a twisted rope or binder twine as a tourniquet to hold the two-stake set tightly in place.

Depending on the strain, you can use other configurations, such as 2-1-1, or even 1-1-1 for a light strain. When using any stake anchor, be sure that it is in direct alignment with the strain being applied.

LOG-AND-STAKE ANCHOR

Log-and-Stake Anchor
Log-and-Stake Anchor

The log-and-stake anchor is easy to make and can hold a considerable amount of pull. You can tie the line directly to the log, or you can use a ring-and-rope grommet as shown in figure 90.

To make the log-and-stake anchor, place a log 4 to 6 inches in diameter perpendicular to the pull of the line. Then drive in four large stakes in front of the log. Next, slip the rope grommet through the ring and then slip the ends of the grommet around the log (see figure 90).

Drive a second row of stakes 24 inches behind the front stakes. Then anchor the front stakes to the rear stakes with a tourniquet made of binder twine or rope.

STROPS

It is good practice to use a device called a strop to avoid damage to your long lines. It also makes it easier to tie off your long lines and to make adjustments.

A strop can be made by using a 10-foot length of 1/2-inch diameter manila or polypropylene rope. To make a strop, splice a thimble and ring into one end of the rope (see figure 91), or use a screw pin shackle with a thimble.

The strop can then be wrapped around a rock or tree to attach the line (see figure 92). It can also be used around a spar that is anchored between two trees (see figure 93).

Strops
Strops

Note: Be sure to use a piece of canvas or burlap to protect your rope from sharp edges of a rock or to protect the bark of the tree from rope burns.

GROMMETS

A grommet is often used in conjunction with an anchor. A large grommet can be made by splicing together the ends of a 10-foot length of 1/2-inch manila or polypropylene rope. If you don’t have a spliced grommet in your pioneering kit, tie the ends of the rope with a square knot or a carrick bend. Be sure to secure the ends of the rope.

The completed grommet is useful when attaching a long line to an anchor of stakes. It provides a strong and more convenient way to attach a guyline or other long line.

The grommet you use must be made of a larger-diameter rope than the guyline to avoid creating a weak link in the chain between the structure and the anchor.

Rope Grommet
Rope Grommet

Single Pull Rope Tackle Monkey Bridge Configuration

PDF FILE for: Anchoring Pioneering Projects

Single Trestle Bridge

SingleLockVertical
Summer Camp: Pioneering Merit Badge Class

CLICK HERE FOR COLOR PHOTOS AND COMMENTARY.

This simple crossing bridge uses only a single trestle and two walkways. The legs of the trestle are extended up above the walkway to provide a way to attach a handrail. The length of the spars listed for the walkways and trestle will be enough to build a bridge that will span a creek or ravine that’s up to 4 feet deep and 18 inches wide.

This project can be broken into three subassemblies: the trestle, the two walkways, and the four light spars for handrails.

Trestle. Begin by building the trestle. The legs for the trestle should be spars that are about 3 inches in  diameter and 8 to 10 feet long. When choosing these spars, take into account the depth of the creek you’re crossing.

The distance from the base of the legs to the top ledger (transom) on the trestle should be about 1 foot higher than the level of the banks of the creek. This will allow the walkways to slant up. Then allow an additional 4 feet in height on the legs from the top ledger up to the top of the legs for attaching the handrail.

The top ledger of the trestle should be about 3″ in diameter since it also acts as the transom and carries all the weight of the walkways and the person using it. The bottom ledger can be smaller: a 2 inch diameter spar will work here.

Drawing 1: Trestle Heeled in with one walkway positioned.
Drawing 1: Trestle Heeled in with one walkway positioned.

The trestle is assembled with Square Lashings to hold the ledgers and the ends of the cross braces to the legs. The center of the cross braces is lashed together with a Diagonal Lashing.

Walkways. The two walkways are assembled as separate sub assemblies. (Refer to Bridge Walkways.) Be sure to make the cross spar at the end of the walkway long enough to attach to both the stakes and the handrails without getting in the passageway.

Assembly. To assemble the bridge, set the trestle in the center of the creek. Heel in the bottoms of the trestle legs by setting them in holes approximately 4 to 6 inches deep (see Drawing 1). This will prevent the trestle from shifting, and is also a way to level the transom spar as the trestle is set in place so that the walkways are level.

Next, put the walkways in position from both sides and lash the walkways’ underspars to the transom (top ledger) of the trestle. Then drive stakes at the other end of the walkways. Lash the ends of the cross spars on the walkways to the stakes.

Handrails. Finally, handrails are provided to help those crossing the bridge and also add strength to the structure of the bridge. When the handrails are added, they form triangles with the walkway and the trestle leg. These triangles produce a strong structure that prevents the bridge from racking. Lash the handrails to the top of the trestle legs and to the stakes with simple Strop Lashings (see Drawing 2).

single_trestle_bridge
Drawing 2: view of assembled bridge with handrails.

List of Materials for a Single Trestle Bridge

  • 2    3-inch x 8 or 10-foot trestle legs
  • 1    3-inch x 4 -foot trestle top ledger (transom)
  • 1    2-inch x 4-foot trestle bottom ledger
  • 2    2-inch x 6-foot cross braces
  • 4    3-inch x 10-foot walkway lateral spars
  • 12  2-inch x 3-foot walkway cross spars
  • 4    2-inch x 3-1/2-foot walkway cross spars
  • 2    2-inch x 10″ x 10-foot walkway planks
  • 4    2-1/2-inch x 12-foot handrails
  • 4    stakes