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Instructors: George Crowl

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1 Instructors: George Crowl
ABL-6 Able Marlinspike This PowerPoint is provided for those who may not have appropriate training aids available in a ship or location. This generally follows a companion lesson plan available at I expect you to modify it to fit your situation and teaching style. I am more concerned that Scouts learn than this fit a specific style. I am, however, a fan of the Effective Teaching model. Teaching EDGE is somewhat simplistic in its approach, but that has some advantages. Note: These lesson plans may also be used for teaching in the ship. For administrative convenience, they cover the entire specific numbered requirement (except one, where Galley is covered separately!). Individual Sea Scout Academy lessons may only cover part of the requirements. Similarly, ships may find that even just a portion of a subrequirement is all that can be done during a particular ship meeting. Adapt these lessons as needed to fit your youth and your situation. Share these plans with your youth who are teaching. Animatedknots.com illustrations were used in some cases. Philosophy: Sea Scout Academy’s primary purpose is to teach the material to the Sea Scout. If the Sea Scout demonstrates mastery of parts of the subject, then the instructor should annotate on the class roster what has been passed, in the instructor’s opinion. Skippers have the right to re-examine any Sea Scout in any requirement. (Knots are not a good subject to give a pass in.) SSA may schedule only portions of ORD-8. Instructors: George Crowl

2 Course Outline a. Complete a back splice, eye splice, short splice, long splice and a palm-and-needle whipping. b. Sew a flat seam, round seam, and grommet eye in canvas or sail material. Describe how each is used in the construction of and the care of sails. Reference: See “Palm and Needle Whipping” p. 114; "Splicing" pp ; “Canvas Work and Sail Repair” pp ; Blocks and Tackles” pp , SSPR pp Equipment Required: Sisal ¼” line, 6’ per student. Whipping twine. Palm and needle. Use the illustrations in the book or in the Sea Scout Pocket Reference. One or more sets of blocks (S502 and S24 have full size sets, S1996 has a small set). Ratio: 1:6 Instructor:Student, youth make good assistants.

3 Course Outline c. Describe the parts of a block and how blocks are sized. Describe the following types of tackle: luff, gun, double purchase, single whip, and runner. With the help of another shipmate, reeve a double purchase tackle. R

4 ABL-6a Complete a back splice, eye splice, short splice, long splice and a palm-and-needle whipping. D

5 Splices We will work from simplest to more difficult Short splice
Eye splice Back splice Long splice All use three-strand laid rope Splicing double braided line is a Quartermaster task I suggest that this PPT be served in small bites. Perhaps just the short splice, until you are ready to move on to the eye splice, etc. I recommend you start with a short splice first. This is simple to start, and students quickly learn the tucking. Then, show them how to start an eye splice. When they have mastered that, show them how to start a back splice. Both morph into the tucks of a short splice. If you do the short splice close to one end (12”) of the 6’ line, then you can do the eye splice on the other end, the back splice next to the short splice, leaving room for the long splice next to the eye. There are some common hints for all splicing of laid rope. We recommend that Sea Scouts start with ¼” sisal, which is inexpensive and relatively easy to work with. First, you must unlay the rope for about 12 times the rope’s diameter, i.e. for ¼” rope, about 3” (or a little more). Next, whip the ends of each strand with narrow tape (masking, electrical, etc.) so they won’t unravel while you are working with them. Finally, you may need a fid to work with large and new ropes. You use the point of the fid to open up the lay of the rope to slide a strand into the rope.

6 Short Splice (1) Easiest / quickest splice to do
Unlay 12 times rope diameter for each rope For 1/2” rope, that is 6” for each rope Wrap tape around all six ends to keep them from fraying (these ends are heat sealed) “Marry” them by sliding separated ends together Short Splice (pp ). The short splice may be the easiest to learn. It serves to join two ropes with little loss in strength. However, it is bulky, and is probably not right to go through a block. After unlaying each rope, and applying the temporary whipping, marry the ends by alternating the strands from each rope. It would help to put a temporary whipping of tape or thread around the join, at this point. Then pick one strand, open up the second opposite strand with your fingers or a fid. Put your strand over the first opposite strand, and under the second opposite strand. Pull against the rope lay. Move to strand 2, do the same thing, then strand 3 and do it again. Do at least three complete sets of tucks on the first side. Trim the strands. When you have completed the first side, remove the whipping and do the second side in exactly the same way.

7 Short Splice (2) Tape the junction to allow you to take your fingers off it Tuck one strand over the opposite strand and under the next Same for all five remaining strands Do that 2-3 more times A

8 Short Splice (3) Tuck all six strands three times minimum
Trim loose ends Roll to smooth Completed splice looks like below, but with nothing sticking out A

9 Short Splice Video Video: A

10 Eye Splice (1) Used to form a fixed loop at the end of a rope
Most dock lines have eye splices in them Most anchor lines have an eye splice around a thimble to attach to the chain May require 5-7 tucks, not 3 Eye Splice (pp ). The eye splice is the strongest loop you can make. Most dock lines have an eye splice in them. An eye splice is a short splice into the same rope. The trick is in getting it started. Unlay 12 times. Whip if you wish. Take the center (1) strand under one strand of the standing end. Take the right hand (2) strand under the next strand so your over and under pattern continues. Take the left hand (3) strand back behind, and go under the previous strand to #1, maintaining your directions. You now have the equivalent of the first full tuck of a short splice. Do at least two more complete tucks, as you would a short splice.

11 Eye Splice (2) Start by unlaying the end of the line
You may need to unlay 7-10 turns with synthetic line Whip it (tape, etc.) Select middle strand (toward you) and slide it under the top strand where you want the loop to form A

12 Eye Splice (3) Pass top strand under next strand
Pass bottom strand under last remaining strand in standing part A

13 Eye Splice (4) Tuck three strands into the standing part
as in the short splice With synthetic line and critical splices, make more tucks! A

14 Eye Splice Video Video: A

15 Back Splice (1) Also called an end splice
A more stable rope end than a whipping Is large like a short splice, therefore not good for a rope end that has to go through a block Relatively simple to do Back Splice (p. 118). The back splice provides a permanent end to a rope, better than a whipping. However, because a back splice is bigger, it is seldom right for a line that must go through a block. Those must be whipped or sealed. To do a back (or end) splice, unlay the rope (1). Pull the left strand behind the center strand; weave the right strand behind the left, in front of the center, and behind and through the hole of the left strand (2). Tighten this down to three horizontal strands 120° apart (3). Then tuck any strand over the first strand below it, and under the second strand (4). Do that for the next two strands in order (5). Tuck each of the three strands again. Tuck each of the three strands a third time (6). Trim any remainder. Roll the completed splice on a hard surface.

16 Back Splice (2) Starting is critical Separate into three strands
Hook middle strand over into upside down “U” Hook right strand through “U” on top then under Hook left strand behind middle strand, then up and over both parts of middle strand A

17 Back Splice (3) Gently tug the strands down, each
strand partially, then fully You should have a tight crown, with three strands going out at 120° angle A

18 Back Splice (4) Tuck “medium brown” strand coming toward you over and under, as in short splice Tuck “dark brown” strand going away on left over and under, toward you Tuck “light brown” strand going away on right over and under, away from you Pull first tucks tight A

19 Back Splice (5) Continue tucking, at least twice more
Total of three or more tucks for each strand Finish the ends of the strands as you would for a short splice A

20 Back Splice Video Video: A

21 Long Splice (1) Long splice uses a lot of line
Almost no reduction of line strength Will go through a block / sheave Unlay 15 turns of line before starting a long splice Marry the lines just as you do for short splice The author is not convinced the diagram in the SSM is accurate in labeling the strands. The principles are, however, clear. Long Splice (Pp ). A long splice will run through a block, and can be hard to detect. It uses a lot of rope, but does not appreciably affect the strength. Unlay the ends of each rope about 15 full turns (a lot more than a short splice). Make temporary whippings. Marry the ropes as you do for a short splice. Take opposite strands, in this case, A and F. Unlay A enough further that F can be laid down in its place (1). Leave enough to tie and tuck two turns. Take the next pair of opposite strands, B and E [I don’t think this illustration is quite right. I am prepared to be proved wrong. I think we should be using B and E.]. Unlay E enough further that B can be lade down in its place (2). Note: the second unlaying is to the opposite side as the first. Tie an overhand knot in A/F so that it lies in the trough. Unlay the F strand so that it can be split in two. Cut one half off, tuck the remainder over/under as for a short splice. Cut off the long A strand to a few inches, do the same on the A side (3). Repeat for each pair of strands. (3) Finish by rolling or pounding the splice well and trimming the ends of the strands so they lie flush.

22 Long Splice (2) Whip or tape if desired
Unlay one strand on the left hand side 15 turns, and lay in the matching strand from the right side Insure it lays in evenly Do the same thing on the right hand side A

23 Long Splice (3) You have three matched line pairs
To minimize making the line larger, split each strand in half. Cut off one half strand where they will join. A

24 Long Splice (4) Tie each pair with an overhand knot, tuck remainder underneath twice Trim and roll to blend it together A

25 Long Splice Alternate Instructions
uctions/3Strand_C1_Long%20Splice_AUG2012_W EB.pdf A

26 Palm-and-Needle Whipping
A Palm is a large thimble that fits in the palm of your hand to push big needles through rope and sailcloth. “Ordinary” whipping will come undone with use and abuse P&N whipping will hold even if some threads are worn or cut You should not need a palm to do Able P&N whipping These instructions are from Seaward, which seemed clear and simple, well illustrated. Palm and Needle Whipping (p. 114). Palm and needle whipping is much more secure than a common whipping. It requires more work, and some equipment, but will be worth the trouble on ropes that get a lot of use. Double twine passed under one strand. End of twine tucked back under the whipping. Wrap the twine firmly around the line, taking care to lay each wrap beside the previous one. Bring twine under a strand and follow “lay” of rope back and under strand on the other side of whipping. Follow the three lays back and forth over the whipping. Finish by bringing twine up through the center of the strand.

27 Whipping (1) Use whipping twine
Thread needle with doubled length of twine Push needle completely through line Knot end of twine, pull to knot A

28 Whipping (2) Start turns away from end, so they cover knot
Make whipping about twice diameter of rope long Make whipping tight, all cord next to previous turn A

29 Whipping (3) Drive needle through center of line, emerging on groove between strands Pull twine tight A

30 Whipping (4) Pass the twine over the groove to the other end
Push the needle through the next strand to the next groove Come back along the groove, repeat Doing it twice is better than just once Called “worming” A

31 Whipping (5) To secure the end, push needle completely through the line, cut off twine as close as possible End result looks like this A

32 ABL-6b Sew a flat seam, round seam, and grommet eye in canvas or sail material. Describe how each is used in the construction of and the care of sails. D

33 Flat Seam Flat seams join two pieces of sailcloth or tent cloth
They cover the raw edge of the fabric, preventing the edge from unraveling Used to repair sails manually Used to make sails with sewing machine Flat Seam (p ). Flat seams are used to join two pieces of canvas or nylon. Lay the two pieces on a flat surface. Overlap the edges you want to join. Fold the top fabric so it is straight. Sew through the lower piece and both layers of the upper piece. When you have finished one side, rub it flat. Turn the joined fabric over. Again, fold the top fabric over straight. Repeat the sewing, and rubbing the seam smooth.

34 Sewing Machine Flat Seam (1)
Lay fabric out, outside to outside Upper fabric is 1/2” inside lower fabric Stitch 1/2” inside upper fabric A

35 Sewing Machine Flat Seam (2)
Spread the two cloths out so the seam sticks up Fold the longer piece over the shorter piece Smooth it flat, and stitch along the edge as shown These instructions miss the point that you still need a second stitch on the other side of the seam (where it was stitched to start). There are sewing machines that do this automatically. Note that this seam is four layers thick.

36 Hand Flat Seam (1) Fold one layer on itself, 1/4-1/2”
Lay on edge of second layer. Pin to hold. Sew by going over edge, into lower cloth, up into upper cloth, as illustrated A

37 Hand Flat Seam (2) Turn both fabrics over
Fold other fabric under, 1/4-1/2”. Pin. Sew this other side the same way If you don't overlap too far, only 3 fabric layers A

38 Round Seam Sews chafing gear onto a line Leather, fabric, etc.
Fold the material so it meets smoothly and tightly Go in one side, out the other, pulling tight Firmer if you go through the line

39 Grommet Device used to reinforce a hole in fabric (sail, etc.) and spread the load Metal pre-formed grommets are much preferred Hand-made grommets are an emergency procedure! Grommet (p ). Grommets are essential to sails and other canvas/nylon products. A properly positioned grommet takes the strain of an attached line and spreads it out to the rest of the sail or canvas. Grommets are pre-made into your sails and other canvas. However, a grommet can pull out, or you may need one in an unusual place when there is no sailmaker available. You can make your own eyes and the grommets to keep them from tearing. Cut a hole in the fabric, don’t poke the hole through. The hole should be somewhat smaller than you want the finished hole to be. Preferably, lay a brass or galvanized iron ring (washer) over the hole. If you don’t have a metal ring, you can make a small grommet out of spliced rope. Get some strong twine, 9- or 10-ply, wax it well. Sew the ring in place, starting on the side away from the point of stress. Work around the grommet, putting your twine into the canvas about 1/8” away from the grommet. Pull your twine tight as you go. When you finish the first circle, go around again, a little further out. Put you new stitches between your first set. If this grommet will take a heavy strain, go around one or two more times. Finish under the grommet ring with some cross stitches.

40 Hand Made Grommet Splice a rope in a ring or use a washer the right size If possible, trim the hole into a circle Repair any tears Use needle and thread to tightly circle the inside of the hole to the outside of the washer A

41 Hand Made Grommet (2) Spread the load by making a second circle, using a second layer on the inside, and your outside stitches 1/4-1/2” further out A

42 ABL-6c Describe the parts of a block and how blocks are sized. Describe the following types of tackle: luff, gun, double purchase, single whip, and runner. With the help of another shipmate, reeve a double purchase tackle. D

43 Parts of a Block Single and double block Without and with becket
Blocks (p. 122). A block is a set of pulleys or sheaves mounted on a single axle. The block is attached to a mast, spar, boom, cross-beam, or a load. Line is reeved through the block. The parts of a block are illustrated. The eye attaches to the solid pulling point, or to the harness. The sheave has a groove for the line; it rolls on the pin in the center of the block. The part where the line goes into and out of the block is called the swallow. The cheeks are the sides that keep everything inside. The tally plate allows you to look at the pin. The becket is a lower attaching point, the tail the bottom of the block. A block can have one or more sheaves. Four is probably the practical maximum.

44 Types of Blocks Snatch Fiddle / Cam Cheek Pad eye Rachet A

45 Blocks for Rope vs Wire Rope will bend around a sheave more readily than wire Wire must have a much larger sheave than rope Rope sheave = 6 x rope diameter Wire sheave = 20 x rope diameter A

46 Block Sizing Blocks are sized by shell (outer) and sheave (rolling part) for a given rope size Shell Sheave Rope Wire 4” ” /2” /8” 5” ” /8” /16” 6” ” /4” /4” Rope – Sheave diameter = rope diameter x 6 Wire – Sheave diameter = wire diameter x 20 Blocks are sized differently depending on whether serving fabric or wire rope. The circumference of natural or synthetic line is multiplied two times to determine sheave diameter, and three times to determine the block shell size. For instance, ½” diameter line is 1½” in circumference, and requires a sheave 3” in diameter. Wire rope should not have a sharp bend, so the sheave size should be at least 20 times the diameter of the rope. ¼” wire rope needs 20/4ths or 5” sheaves.

47 Whip Tackle Whip tackle changes direction of pull
Does not change force required or amount of line pulled, because only one rope supports weight One single block The right hand illustration shows a weight of 100 Newtons (a scientific measure), being lifted 10 cm with 10 cm pull on a line on which we have to exert a force of 100 Newtons. While this illustration is not a lot different, the next three similar ones will show more what a block and tackle looks like. Tackle (pp ). Tackle is a series of blocks with line reeved between that that allows a trade of line length for lessened load. If you have a 100 pound weight on the floor and want to lift it with a single pulley attached to a beam, you have a single whip tackle. You will need to exert 100 pounds of force on the downward rope to lift the 100 pound weight. You don’t gain any mechanical advantage, but you change the direction of the pull.

48 Runner Tackle Runner tackle does not change the direction of pull, it is still up Two ropes support the weight, so each rope has 50 lbs supporting, just 50 pounds to lift Have to pull in twice as much rope to lift the weight. Imagine standing on the black line lifting. One single block A runner tackle is the next tackle in a series that lessens the pull required, but makes you run more rope through the pulleys. In a runner tackle, the weight is free to move along the rope, and you must pull up. Two ropes supporting the weight mean that the force on each rope is 50 pounds. You can lift the weight by exerting a 50 pound pull on the line, but you will have to pull twice as much line to raise it the same distance. This direction can be inconvenient though.

49 Gun Tackle Used 200 years ago to position frigate guns
Only 2:1 weight and rope pulling ratio Changed direction of pull Two single blocks (one with becket) This second illustration shows more what a gun tackle looks like. Lifting 10 cm by pulling 20 cm of rope, and only using 50 Newtons of force. A gun tackle A gun tackle line is attached to the becket of the top block, reeved through the lower block, and reeved through the upper block. Again, two ropes supporting the weight means 50 pounds pull, and twice as much rope. A gun tackle allows you to pull in the opposite direction of the weight (pulling down from a beam, rather than up to a beam.

50 Luff Tackle Luff tackle has three supporting lines
Therefore 1/3 the weight, 3x line to be pulled One double block and one single block (becket) A luff tackle is the next step. Attach the line to the lower block. Have two sheaves in the upper block. Now there are three lines supporting the weight, 33 1/3 pounds on each line. You pull 33 pounds, but three times as much line.

51 Double Purchase Tackle
Double purchase has four lines supporting weight Therefore ¼ the weight, 4x the rope pulled Two double blocks Common for mainsail sheets Some mainsails use triple purchase tackles Medium size (20-30 foot) sailboats will use double purchase. Most 30-foot sloops and larger will use a triple purchase tackle on the mainsheet. A double purchase is two sheaves in each block, four lines, 25 pounds, four times as much line. In reality, you always lose something to friction, about 10% more for each sheave.

52 Friction Loss There is a friction loss from the theoretical figures of 50%, 33% and 25% Plan on 5-10% loss per sheave, depending on the bearings in the sheave A

53 Reeving Block & Tackle Competition reeving (Minto) can be done as illustrated below Line attached to becket, in / out one side other block, back to same side first block Down second block again, other side, and back to first block I could not find a double block illustration. Minto Rendezvous uses triple blocks to reeve a double purchase tackle, so this is realistic. Just use two of the three sheaves. Reeving a double purchase tackle requires some thought to keep the lines from fouling each other. To minimize line handling, run the working end of your line through one side of the upper block. Set your lower block about three feet away to give you working room but be close. If using a hook, make sure it is properly positioned. Bring your working end through the same side of your lower block. Bring your working end back to the empty side of the upper block. Continue down to the empty side of the lower block. Attach your line to the becket (bottom) of the upper block with a bowline or other firm knot. Then stretch your tackle to fit the job. The main sheet on a 30 foot sailboat is often controlled with a double purchase tackle.

54 Questions? R


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