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ABL-6. Able Marlinspike. Instructors: George Crowl. Course Outline. a. Complete a back splice, eye splice, short splice, long splice and a palm-and-needle whipping.
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ABL-6 Able Marlinspike Instructors: George Crowl
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.
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.
ABL-6a Complete a back splice, eye splice, short splice, long splice and a palm-and-needle whipping.
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
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 (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
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
Short Splice Video • Video: www.animatedknots.com/spliceshort
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 (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
Eye Splice (3) • Pass top strand under next strand • Pass bottom strand under last remaining strand in standing part
Eye Splice (4) • Tuck three strands into the standing part as in the short splice • With synthetic line and critical splices, make more tucks!
Eye Splice Video • Video: www.animatedknots.com/splice/
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 (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
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
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
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
Back Splice Video • Video: www.animatedknots.com/backsplice/
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
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
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.
Long Splice (4) • Tie each pair with an overhand knot, tuck remainder underneath twice • Trim and roll to blend it together
Long Splice Alternate Instructions • www.samsonropes.com/Documents/Splice%20Instructions/3Strand_C1_Long%20Splice_AUG2012_WEB.pdf
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
Whipping (1) • Use whipping twine • Thread needle with doubled length of twine • Push needle completely through line • Knot end of twine, pull to knot
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
Whipping (3) • Drive needle through center of line, emerging on groove between strands • Pull twine tight
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”
Whipping (5) • To secure the end, push needle completely through the line, cut off twine as close as possible • End result looks like this
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.
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
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
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
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
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
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
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!
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
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
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.
Parts of a Block • Single and double block • Without and with becket
Types of Blocks • Snatch • Fiddle / Cam • Cheek • Pad eye • Rachet
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
Block Sizing • Blocks are sized by shell (outer) and sheave (rolling part) for a given rope size • Shell Sheave Rope Wire 4” 3” 1/2” 1/8” 5” 4” 5/8” 3/16” 6” 5” 3/4” 1/4” • Rope – Sheave diameter = rope diameter x 6 • Wire – Sheave diameter = wire diameter x 20
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
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
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)
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)