    [Plow LC-61 (Cable)]
    [From the U.S. Government Publishing Office, www.gpo.gov]

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    WAR DEPARTMENT TECHNICAL MANUAL
    NON-CIRCULATING
    PLOW LC-61
    (CABLE)
    WAR DEPARTMENT
    NTSU LIBRARY
    1 2 JUNE 19 44
    WAR DEPARTMENT TECHNICAL MANUAL
    T M 11-370
    PLOW LC-61
    (CABLE)
    WAR DEPARTMENT •
    12 JUNE 1944
    United States Government Printing Office
    Washington : 1944
    WAR DEPARTMENT, Washington 25, D. C., 12 June 1944.
    TM 11-370, Plow LC-61 (Cable), is published for the information and guidance of all concerned.
    [ A.G. 300.7
    By order
    (6 May 44).]
    of the Secretary of War:
    G. C. MARSHALL, Chief of Staff.
    Official :
    J. A. ULIO,
    Major General,
    The Adjutant General.
    Distribution :
    As prescribed in paragraph 9a, FM 21-6; Armies (2) ; Corps (2) ; Sv C (10) ; Dept (1) ; Def Comd (1) ; D (2) ; I Bn 11 (3) ; IC 11 (6) ; Sig C Labs (15) ; P/E (25) ; ASF Dep (10) ; Sig C Dep (15) ; Sig C Rep Shops (10) ; Sig C Inspection Zones (5) ; Sig C Procurement Dist (5).
    I Bn 11: T/O and E 11-15, Sig Bn; T/O 11-25, Sig Cons Bn; 11-225, Sig Cons Bn Avn; 11-335, Sig Bn, Grd-A Spt Comd.
    I C 11: T/O and E 11-27, Sig L Cons Co; 11-67, Sig Hv Cons Co; 11-500, Sig Sv Orgn as follows: Column GP, Spiral 4 Cable Sec, Column GS Hv Wire Cons Team, Column GT L Wire Cons Team; T/O 11-107, Sig Dep Co; 11-127, Sig Rep Co; 11-277, Sig L Cons Co, Avn; 11-287, Sig Co Dep, Avn; 11-300-1, Hqs, Sig Sv Co; 11-327, Sig Port Sv Co; 11-587, Sig Base Maint Co; 11-597, Sig Base Dep Co.
    For explanation of symbols, see FM 21-6.
    II
    CONTENTS
    Paragraph Page
    SECTION I. DESCRIPTION.
    General.................................... 1	1
    Physical characteristics ........................ 2	1
    Main components and accessories ................. 3	2
    Identification of parts ......................... 4	3
    Motive power for Plow LC-61 (Cable) ............. 5	6
    II. INSTALLATION AND OPERATION. Unpacking ........................................... 6	7
    Assembling Plow LC-61 (Cable) ................... 7	7
    Limitations of use of plow ...................... 8	10
    Methods of burying wire or cable................. 9	11
    Advance planning ............................... 10	11
    Plowing depth .................................. 11	12
    Rate of speed .................................. 12	13
    Plowing team ................................... 13	13
    Plowing operations ............................. 14	14
    Precautions to be observed while plowing ....	15	15
    Procedure at splice or connector points.....	16	16
    Passing road crossings ......................... 17	17
    Use of culverts ................................ 18	17
    Crossing streams and swamps .................... 19	18
    Restoration of ground surface after plowing	20	19
    Marking locations of splices or connectors ...	21	19
    Marking buried wire and cable lines for identification and direction ......................... 22	20
    Recovery of buried wire	and	cable .......... 23	21
    Installation of cable recovery	attachments ...	24	24
    Precautions against mechanical injury to wire and cable ....................................... 25	25
    Removal of cable ............................... 26	25
    Transporting plow .............................. 27	26
    III
    Paragraph Page
    SECTION III.
    IV.
    FUNCTIONING OF PARTS.
    Attaching tow .............................. 28	27
    Placing wire or cable in feeding channel of plow ....................................... 29	27
    Tripping and lowering	standard ............ 30	28
    Starting to plow ........................... 31	28
    Lubrication of wire	or	cable	being- plowed-in 32	29
    Removing wire or cable from feeding channel of plow .................................... 33	29
    Raising standard ........................... 34	30
    Use of coulter ............................. 35	30
    Procedure when plow is caught by under-„ ground obstruction ....................... 36	30
    MAINTENANCE.
    Lubrication ................................ 37	32
    Care of tires .............................. 38	32
    Adjusting lifting-hook trip plates ......... 39	32
    Spare parts attached to plow ............... 40	33
    Repairing worn and broken parts ............ 41	33
    Replacing point ............................ 42	34
    Replacing shin ............................. 43	34
    Replacing coulter blade .................... 44	34
    SUPPLEMENTARY DATA. Maintenance parts list ..................... 45	35
    IV
    DESTRUCTION NOTICE
    WHY—To prevent the enemy from using or salvaging this equipment for his benefit.
    WHEN—When ordered by your commander.
    HOW—1. Smash—Use sledges, axes, handaxes, pickaxes, hammers, crowbars, heavy tools.
    2.	Cut—Use axes, handaxes, machetes.
    3.	Burn—Use gasoline, kerosene, oil, flame throwers, incendiary grenades.
    4.	Explosives—Use firearms, grenades, TNT.
    5.	Disposal—Bury in slit trenches, fox holes, other holes. Throw in streams. Scatter.
    USE ANYTHING IMMEDIATELY AVAILABLE
    FOR DESTRUCTION OF THIS EQUIPMENT
    WHAT—1. Smash—Gate, tow bar, guides, sheaves, any and all moving parts.
    2.	Cut—Springs, wires, tires, tow rope.
    3.	Burn—Instruction books, tires, drawings.
    4.	Bury or scatter—Large square-headed bolts, any or all the parts listed above after bending or breaking them.
    DESTROY EVERYTHING
    V
    SECTION I
    DESCRIPTION
    1.	General
    a.	Plow LC-61 (Cable) is designed to plow-in wire or cable up to approximately 1 inch in diameter. At a speed up to 5 miles per hour, it is possible to plow-in each of the following at one operation:
    (1)	Two Cables WC-548 (spiral-four).
    (2)	One 5-pair cable.
    (3)	One 10-pair cable.
    (4)	Six pairs of field wire.
    Note. In extreme cases, and under ideal conditions over short distances, 12 pairs of field wire may be handled at the same time by plowing at slow speeds.
    b.	The plow can be adjusted to bury wire or cable at depths from 6 to 18 inches. Instructions for overcoming underground obstacles are given in paragraph 36.
    c.	Plow LC-61 (Cable) also is used to recover field wire and cable when a cable recovery device is attached to it. This recovery device can be mounted or dismounted easily (figs. 7, 8, and 9), and it is satisfactory when used in soils other than hardpan or very rocky ground, if cable or wire has been buried from 6 to 20 inches deep.
    2.	Physical Characteristics
    a.	For domestic use, Plow LC-61 (Cable) is shipped either completely assembled or disassembled in five separate packages. For oversea shipment, Plow LC-61 is packed in a single box.
    b.	Plow LC-61 weighs approximately 1,500 pounds assembled. It is ruggedly built and, with reasonable care and maintenance, will give satisfactory service.
    c.	Tractive equipment recommended for use in towing the plow is described in paragraph 5. Use of this equipment as directed will help the plow withstand difficult terrain conditions without damage.
    d.	Plow LC-61 is equipped with the same type of standard
    1
    pneumatic tires, wheels, and wheel bearings as the 1/4-ton, 4x4 truck. In transporting, the plow may be towed overland at ordinary speeds when it is attached directly to the pintle of a truck by a towing bar or a 10-foot steel rope (both supplied), or it may be carried on a truck. When plowing, the towing bar helps in backing up the plow to overcome obstacles.
    e.	A square hole in the gate, which fits the standard guide clamp bolts and standard clamp bolts, makes it possible to use the gate as a wrench. Many of the bolts and nuts on the plow fit the openings of lineman’s Wrench LC-25-A. Alemite grease fittings are placed on the plow assembly at points which require this type of lubrication.
    f.	A locking pin in the holding frame upright acts as a safety stop. This pin prevents the standard from falling if it becomes unhooked while the plow is being towed overland.
    3.	Main Components and Accessories
    Plow LC-61 (Cable) consists of the following main parts:
    1	frame assembly with front wheels, coulter and coulter control, trip lever, axle bearings, front cable sheave and guide, extra shin, extra point, extra gate, wire reel axle, and Talc Box M-401)
    1	standard assembly with rear cable sheave and guide assembly.
    1 axle and tumbling arm.
    1 lifting-hook assembly.
    1 holding frame assembly with trip links, holding block and center cable sheaves and guide assembly.
    1 sliding bar with adjusting screw and depth-adjusting nut.
    1 reel support with wheel scrapers.
    1 hitch plate.
    2 wheels and hubs with pneumatic tires mounted, less bearings.
    1 box of wheel bearings.
    1 towing bar.
    1 towing-bar pivot frame.
    1 towing cable.
    2 stops.
    2
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    Figure 6. Method of marking splices and connectors. tl-50031
    19
    (1)	To make delays as short as possible when replacing damaged lengths of wire or cable.
    (2)	Testing.
    (3)	Emergency talking connections.
    (4)	Recovery of cable.
    b. Method. Markers and stakes used for indicating the location of splices and connectors are often displaced, removed, or overgrown. The following method of marking locations (fig. 6) is outlined:
    (1)	At the splice point, dig a hole about 30 inches long, 18 inches wide, and 12 inches deep.
    (2)	Place the slack, or loop of the wire or cable in this hole. If marline has been used to hold the loop during plowing operations, do not remove it. However, if clamps have been used, remove them.
    (3)	Fill the hole with the earth that has been removed.
    (4)	Place additional earth up over the splice, obtaining this earth from a hole dug 6 feet off the line directly opposite the mound. This second hole should be about 3 feet in diameter and about 6 inches deep. Do not refill it.
    (5)	In the unfilled hole at the edge of the nearest cable, drive a wooden stake so that about 9 inches extend, above the bottom of the hole. The stake should be long enough so that it cannot be easily knocked over.
    (6)	Marks such as the mound, the hole, and the stake will remain distinguishable long enough to make it possible to find the splice or connectors without much trouble. When required, coded information about the splice, its number, and the distance from the terminal can be written on a wooden stake with a soft pencil or crayon.
    22.	Marking Buried Wire and Cable Lines for Identification and Direction
    a.	Avoiding Confusion. To avoid confusion in testing, and to carry out maintenance duties more effectively, a certain amount of marking of buried cable is necessary. Use code to show this information. The following information usually is furnished by marking:
    (1)	The trend of the line at connector or splice points.
    (2)	The number of cable sections back to some terminal point.
    (3)	Identification of one cable from another when two or more underground cables are placed together.
    b.	Indicating Trend. An effective way to indicate the trend of a line is to wrap a few turns of friction tape, rubber tape,
    20
    or copper wire around a cable or wire not more than 6 inches from the connector or splice. Apply this marking tape or wire to the length extending away from the origin point of the line.
    c.	Using Tags. Writing on paper or linen tags does not remain legible when buried. Two cables can be identified, however, by attaching a tag to one. When information is furnished regarding splice number, wire or cable number, or the distance from the origin of the line, place this information above ground for quick reference in maintenance work. Write the information, suitably coded, directly on the planed surface of a stake with a soft lead pencil or black lumber crayon. If tags are found upon which the markings will remain legible, even in exposure to weather, tie them to stakes, trees, or bushes.
    23.	Recovery of Buried Wire and Cable
    a.	Marking Route. Mark out the exact route when wire or cable is to be removed, except in places where it can be stripped out of the ground. When there is no remaining evidence on the surface to indicate where the plow has passed, use electrical-locating methods, such as an exploring coil, by applying tone to the buried wire or cable. Place stakes so that the recovery team can locate them quickly, and can follow all deviations in the route.
    b.	Methods. Recover buried wire or cable for re-use whenever possible. Methods used for recovery vary with the types of soil in which wire or cable is buried, and the depth at which it is buried.
    (1) Stripping. Where wire or cable has been buried in loose soil, such as sand or loam which is not compact, and the wire or cable is not buried very deep, strip it out of the ground and reel it up by means of Reel Unit RL-31 or RL-26 mounted in a motor vehicle which is run back over the path of the wire at slow speed. Though this is a comparatively rapid method, there is danger of injuring the wire or cable by too great tension and sharp bending. It is not necessary to know the exact location of the wire or cable after an end has been located.
    (2) Cable recovery device. The cable recovery attachments for Plow LC-61 (Cable) loosen the soil above the wire or cable and partially open a trench. The attachments consist of two parts: a flat plate (made in both 9-inch and 16-inch widths) which bolts to the standard in place of the plow point, and a pair of mold boards secured to a member which replaces the usual shin. Often, loosening the soil with the flat plate is all that is needed to allow the wire and cable to be pulled out of the ground.
    21
    However, when it is necessary to remove loosened clumps of soil, the mold boards are used in addition to the plate.
    Figure 7. Mold boards and plates of recovery device.
    (a)	Use of recovery attachments. Use of the plate alone or the plate and the mold boards together for recovery with a minimum of hand digging and damage to the cable or wire, depends on local conditions. The plate alone generally will be adequate in sandy soils and loams, while in clay and stony soils, or where there is heavy sand, use of the mold boards may be necessary. The mold boards disturb the ground surface much more than the plate does. Where great disturbance on the surface is objectionable, as on the shoulders of roads, use of the plate alone is better if it sufficiently loosens the soil. The plate, however, must not penetrate to such a depth that there is danger of it touching the cable. To allow for variations in the operation, the right depth is generally at least 2 inches less than the depth of the cable. Determine fairly accurately the cable depth. The most convenient way to do this is by digging a number of test holes along the route.
    22
    Figure 8. Recovery device when one plate is used.
    (b)	Since the plow will dig deeper with the recovery attachments in place than with the ordinary point for any given setting, this should be considered when making depth adjustments. To obtain the correct depth setting for the plow, make a few short trial runs to one side of the cable; measure the depth in each case, and adjust until certain of the proper depth setting before attempting to run the plow over the cable. Use the adjusting screw to aid in making minor depth adjustments.
    (c)	Soil conditions determine whether the 9-inch or the 16-inch plate is used. Generally, the 16-inch plate is chosen because this width permits a greater deviation of the plow track over the cable. When the soil is hard or stony, however, the 16-inch plate may ride out of the ground or may require more power than is available. Use the 9-inch plate in these cases.
    Note. The 9-inch plate, together with the mold boards, also can be used to provide an open trench in which to bury larger cables than can be fed through the Plow LC-61 (Cable).
    23
    Figure 9. Recovery device, rising mold boards and plate.
    (3) Agricultural plow. When the cable recovery device is not available, loosen the surface of the soil over the wire or cable with an agricultural plow, then strip the cable out, using the same method as in loose soil ((1) above). Do not turn the furrow deeper than 2 inches above the wire or cable.
    C auction: Always examine the share of an agricultural plow used in recovering wire, to make certain that its edge is not sharp enough to damage wire and cable. Smooth off the rough edges to reduce the possibility of such damage.
    (4) Hand tools. Dig up the wire or cable with hand tools when other methods cannot be used. Also, where the agricultural plow has not cut deeply enough, use hand tools to free the wire or cable. Use a scooping motion along the conductors rather than a cutting or digging motion, so that the wire or cable will not be damaged.
    24. Installation of Cable Recovery Attachments
    a. Plate. Remove the point used on the plow when burying cable by taking out the two plow bolts holding it to the standard. Use the same plow bolts, to attach either the 16-inch or the 9-inch plate in place of the point.
    Note. If a plate is to be used without the mold boards, do not remove the shin. The bolts used for the point are 5/8-inch No. 3 plow bolts, one 3 inches long and one 4 inches long. In an emergency, any type of 5/8-inch bolts can be used, but they must be of the countersunk head type or the heads will wear off rapidly,
    24
    TL5O787
    b. Mold Boards. (1) Remove the shin at the front of the plow standard by taking out the bolt at the top which clamps it between the gusset plates.
    (2)	'Pill, the top of the shin forward from between the gusset plates; lift out the shin.
    (3)	Put the mold board assembly in position by first placing the lower end of the stem in the slot between the landsides in the same manner as the shin; then, tilt the upper end of the stem back between the gusset plates and adjust it so that the bolt hole in it lines up with the holes in the plates.
    (4)	Put the same bolt which was used for the shin in the holes and tighten it enough to pinch the top of the stem firmly between the plates so that no movement can take place.
    Note. Examine the plate and mold boards for looseness while using the plow and tighten the bolts holding them, if necessary.
    25.	Precautions Against Mechanical Injury to Wire and Cable Be careful to avoid cutting or crushing the insulation when wire or cable is being handled. Pay constant attention to the wire or cable as it passes into the plow to guard against kinks or too great tension. In stony soil, be careful to bury wire or cable deep enough so that it will not be pinched between stones by pressure of heavy vehicles. Be careful not to damage the insulation when working around wire or cable with hand tools. While wire or cable is being picked up, examine it carefully for cuts and other damage. Repair damaged cable before using it again. When the reeling is complete, test each length for continuity, shorts, and grounds. When any of these are found, mark the reel so that it will not be assigned for re-use before repairs are made.
    26.	Removal of Cable
    After the recovery attachments have been used, cable or wire should be removed either by hand or by some mechanical process that will not cause tensions strong enough to injure the cable through sharp bending or crushing in case the cable becomes caught on a root or stone. In such cases, careful handling frees the obstruction.
    Note. Where soil conditions are favorable and cable has not been installed long enough to allow the soil to be compacted, the cable can be removed without use of the trencher equipment. Where cable or wire is buried deeply and the soil is compacted and filled with stones, the removal for spiral-four cable in serviceable condition will be impracticable. Between these extremes, the use of the trencher equipment helps in recovery of spiral-four cable. The extent of damage to the cable in the process of removal will vary consider
    25
    ably; the amount of necessary testing’ and repair work determines the practicability of its recovery.
    27.	Transporting Plow
    a.	Towing. The plow can be towed behind a vehicle, or can be transported in the body of a cargo truck. Use the following procedure for towing:
    (1)	Raise the standard and insert the locking pin (25) above the sliding-bar assembly (3). This forms a safety stop that will prevent accidental lowering of the standard.
    (2)	Slide the standard guide clamp (12) to the top position, and clamp securely.
    (3)	Engage the eye on the hitch plate (44) with the towing hook on the towing vehicle.
    b.	Transporting by Truck. (1) It is not necessary to change the standard guide clamp setting when the plow is to be loaded on a truck. Raise the standard, however, and insert the locking pin (25) above the sliding-bar assembly (3).
    (2)	When a derrick and winch are available, raise the plow by attaching the hoisting line to the button (32) below the lifting eye (33). Pass the eye of the hoisting rope through the lifting eye, and then place it over the button.
    (3)	If skids are to be used, roll the plow up the skids from the ground to the truck platform. Remember that the plow weighs 1,500 pounds.
    (4)	If a steep bank is near, the plow may be loaded directly on the truck by using skids. Do not use the tail gate of the truck to support the weight of the plow.
    (5)	When loaded, lash the plow securely or chock it, to prevent it from moving during transportation.
    26
    SECTION III
    FUNCTIONING OF PARTS
    28.	Attaching Tow
    The towing bar (56) for the plow has an eye which engages the towing hook of the cargo truck. If a tow line is used instead of the towing bar, remove the towing bar and turn it back along the beam. Pass one end of the loop of the towing line through the towing hook on the truck. Pass the other loop through the top of the towing eye (44) on the plow-hitch plate, and engage it in the hook (45) on the lower edge of the hitch plate. When turning corners, the tow bar will pivot or swing only 30° to either side of the center line of the plow. Therefore, when plowing, do not try to force a change in direction of more than 30° with the standard in the ground, as it may shear bolts holding the towing bar.
    29.	Placing Wire or Cable In Feeding Channel of Plow
    a.	If paying out wire or cable from a reel—
    (1)	Place the plow over the starting point.
    (2)	Have the frame in a raised position.
    (3)	Open the lid of the talc box.
    (4)	Remove the feeding channel gate.
    (5)	Place the wire or cable over the center sheave and guide (5), through the talc box (57), over the rear sheave and guide (14), and into the feeding channel.
    b.	If cable or wire has been laid on the ground—
    (1)	Pass it through the front sheave and guide (1), through the talc box (57), and through the rear sheave and guide (14). Place the lower end of the gate (17) against the rear of the standard (18), a little above the lower notches, and place one foot lightly against the gate.
    (2)	Snap the upper end into the latch hooks. The front sheave and guide can be used on either side of the plow.
    27
    30.	Tripping and Lowering Standard
    To trip the standard—
    a.	Remove the locking pin (25), and have the depth-adjusting nut (38) toward the handle end of the depth-adjusting screw (37). To operate this screw quickly, shift the handle (40) until it projects equally on either side of the screw, and can be spun around.
    b.	Before pulling the trip lever, stand clear of the plow so that the sole of the standard rests on the ground. Pull back on the trip-lever control rope (30).
    31.	Starting to Plow
    a.	Methods. (1) Release the plow standard. Place the wire or cable in the feeding channel (par. 29). Pull about 3 feet of wire or cable out of the rear of the standard, and anchor the end to a stake driven for the purpose. Pull the plow forward; the point will enter the ground. After the plow has moved forward 4 feet, the plow standard has reached the depth for which it is set. The wire or cable should slope from the surface of the ground for a few feet.
    (2)	Anchor the wire or cable (a above). Place the plow standard in a hole which has been dug to the depth of the standard setting. As the plow is pulled forward, the point will enter the side of the hole at that depth. Use this method if the first few feet of buried wire are to be fully covered. Use it also when laying small lead-sheath cables.
    b.	Fastening Wire or Cable. If a tree or other fixed object is available, use it to fasten the end of the wire or cable, instead of driving a stake. The conductors also may be fastened to a previously laid section of cable. Use a marline or field wire tie, or an approved cable clamp or grip. Never leave the end of the wire or cable unsecured, as it may follow the plow for a short distance and leave a gap between two sections.
    c.	Watching Plow. Give the truck driver the signal to proceed. Watch the plow carefully to be certain that the correct depth is being maintained, that kinks do not enter the guides, and that clumps of sod and vegetation do not pile up and drag under the frame.
    d.	Adjustments. Adjust the plow if the depth is not right. Four variables affect the maintenance of the right depth. They are: the consistency of the soil, the uniformity of the soil, the angle of the plow sole to the ground, and the weight of the plow. To adjust the plow to compensate for these variables, adjust the
    28
    height of the standard (18) in the frame by using the depth-adjusting screw (37) (par. 116 (4)), or add weight by having men stand on the steps (20).
    e.	Signals. The plow operator signals the truck driver by whistle code, or by interconnected telephones when he is riding in the back of the truck.
    32.	Lubrication of Wire or Cable Being Plowed-in
    a.	Need for Lubrication. When rubber-covered cable has no lubricating coating on the outer surface, and the cable enters the feeding passage under some tension, a snubbing action around the curved portion of the passage will be set up, resulting in the cable leaving the plow under dangerous tension. When burying cable in this condition, it is very important to make sure that the cable is slack as it is picked up. If the cable enters the plow with tension as low as 15 or 20 pounds, it may be damaged.
    b.	Talc Box M-401. Talc (powdered soapstone) is applied with Talc Box M-401 to lubricate the surface of the wire or cable. The talc box (57) is clamped to the supporting arm of the rear sheave and guide, at a height to permit the cable to pass through it before passing over the rear sheave. Put the wire or cable into the box by placing the conductor in the troughlike bottom, and push the cable or wire down between the rubber shields in the slots in the box ends. Fill Talc Box M-401 with powdered talc, and close the cover. The wire or cable is lubricated with talc by passing through the box as the plow moves forward. If the talc box is not available, run the cable through a cloth to which talc has been added freely.
    c.	Water. Use water as a lubricant when talc is not available. Apply the water by allowing it to trickle into the feeding passage of the plow from a small hose (3/16-inch or 1/4-inch) leading from a drum or tank in the truck body or on the plow. On the truck, tie a hose on the reel support at the rear cable guide, with the end just inside the feeding passage. This end should be visible so that the operator can see that water is flowing.
    d.	Oil. If jute-protected or bare lead-sheath cable is being plowed-in, treat the cable with oil when any friction develops in the plow. Waste engine oil will do for this purpose.
    Caution: Do not use oil on rubber-covered cable.
    33.	Removing Wire or Cable from Feeding Channel of Plow Operation of the gate latch lever (15) releases wire or cable from the plow. If the operator rides on the steps, he pushes the lever
    29
    back with his foot. When the operator walks behind the plow he pulls the trip chain attached to the lever. Pulling the lever unlocks the gate (17) and lifts it out of the retaining notches. The same chain which operates the latch lever also attaches the gate to the plow. Always release the wire from the feeding channel before raising or backing the plow.
    34.	Raising Standard
    a.	Procedure. To raise the standard out of the ground, proceed as follows:
    (1)	Release the gate (17).
    (2)	Engage the lifting hooks (27) by pushing forward on the lifting-hook lever (4) until the hooks on both sides have caught the roller lugs in the racks (47) attached to the rear wheel hubs.
    (3)	Continue the forward movement of the plow. This raises the standard out of the ground, and releases the lifting hooks. If the lifting hooks fail to disengage, adjust the lifting-hook trip plates (par. 39).
    Caution: Always pull the plow forward until the hooks release. Stand clear of the lifting hooks and lever because they spring back sharply when disengaged.
    b.	Increasing Traction. On marshy or icy ground, there may not be enough traction from tires to raise the standard out of the ground. When this is true, disconnect the plow from the truck, back the truck far enough to pass the loop of the towing line under the center sheave (5), and hook the line over the notch (7) near the top of the tumbling arm (8). Chock the plow wheels. Pull the plow forward until the frame and standard are raised and latched.
    35.	Use of Coulter
    The coulter (28) is used when the plow is operated in soil overgrown with vines and roots. Use of the coulter reduces the tendency for debris to build up across the shin. Lower or raise the coulter by moving the coulter control lever (39) backward or forward. When the coulter is not needed, it should always be kept ra;sed. This is especially true when plowing over rocky ground or roadways.
    36.	Procedure When Plow Is Caught by Underground
    Obstruction
    When the point of the plow contacts an underground obstruction that is firmly fixed, pass over the obstruction by releasing the gate
    30
    (17) and clearing the wire or cable before raising the standard. Pull the wire or cable out of the trench for a few feet, and move the portion above ground to one side, where it will not become damaged. Proceed by one of the following methods:
    a.	If ground traction is good, back the plow 6 feet or more. Use the lifting hooks to raise the plow frame, and pull the plow forward, raising the standard over the obstruction. If the towing bar is used, back the plow with the towing truck. If the towing rope is used, back the plow by pulling on the hook (22) at the rear of the plow with a line attached to a light motor vehicle.
    b.	If ground traction is poor, move the plow back so that it will be well clear of the obstruction. Be sure to chock the wheels well to prevent any forward movement. Raise the standard (a above).
    c.	If a truck equipped with derrick and winch is available, back up the plow and lift it clear of the obstruction by attaching the winch line to the lifting eye on the plow.
    d.	Relieve any strain on the towing line or bar. Loosen the upper standard clamp bolt (51) and remove the lower bolt. Pull the plow ahead, so that the standard pivots as it is dragged over the obstruction. As soon as the plow has moved over the obstruction, engage the lifting hooks (27) and raise the standard. This will cause the standard to swing back into normal position. Replace the lower bolt and tighten both bolts. Trip the standard. Replace the wire or cable and the gate. If necessary, allow enough slack to bury the wire or cable around the obstruction. Tie any slack to a stake. Resume plowing in the normal manner.
    31
    SECTION IV
    MAINTENANCE
    37.	Lubrication
    a.	The moving parts of Plow LC-61 (Cable) are easily lubricated because of the location of the Alemite fittings. Lubricate all moving parts before using the unit, and frequently thereafter. The Alemite fittings are located at the following points:
    (1)	The two front wheel hubs.
    (2)	Coulter axle bolts.
    (3)	Two rear wheel hubs.
    (4)	Four rear axle bearing caps.
    (5)	Front cable guide axle bolt.
    (6)	Center cable guide axle bolt.
    (7)	Rear cable guide axle bolt.
    b.	The lightest grease-gun lubricant used on motor vehicles under comparable climatic conditions lubricates all moving parts of the plow unit satisfactorily. Grease-gun lubricants recommended are general purpose grease No. 0, U. S. Army 2-106, for temperatures below 32° F., and general purpose grease No. 1, U. S. Army 2-107, for temperatures above 32° F. Use engine cylinder oil for other parts needing lubrication. The engine cylinder oil recommended is engine oil U. S. Army 2-104B.
    38.	Care of Tires
    Tires used on Plow LC-61 (Cable) are high traction, nondirec-tional six-ply mud and snow tread, 6.00x16 inches. Inflate and care for them as for tires on a 1/4-ton truck, or similar vehicles under similar climatic conditions. Keep tires inflated to 30 pounds, and check inflation before using the plow.
    39.	Adjusting Lifting-hook Trip Plates
    The lifting hooks (27) should trip from engagement with the rack roller lugs (47) as soon as the sliding-bar stop-pin roller has moved 1/2 inch beyond the forward edge of the holding block. If the lifting hooks release before the sliding-bar stop pin is com
    32
    pletely over the top of the hoisting block, the plow will not remain in a raised position. To correct this condition, loosen the tripplate bolts (26), and move the plates up a little at a time until the lifting hooks operate correctly. If the hooks fail to release, lower the trip plates.
    40.	Spare Parts Attached to Plow
    Bolted to the left side of the frame are an extra point, shin, and gate. Bolts are provided for attaching the point and shin to the standard. After these parts have been removed for use, replace them with a new set of spares. Paragraph 45 gives a complete list of maintenance parts.
    41.	Repairing Worn and Broken Parts
    a.	Plow LC-61 (Cable) is constructed almost entirely of steel shapes and castings containing 0.35 to 0.45 percent carbon. Occasionally these parts become worn and broken. Usually it is practicable to re-form damaged parts and build up worn parts, such as the point, shin, standard, and landside, by oxyacetylene or electric arc welding.
    b.	When the oxyacetylene method of welding is used—
    (1)	Clean the metal thoroughly with a wire brush. Using an oxyacetylene torch adjusted for a carbonizing flame (excess acetylene), apply any high carbon steel rod to the worn part, building the part up to its original size.
    (2)	Heat the base metal to a sweating temperature; flow onto the surfaces, subject to abrasive wear, a layer (not thicker than 1/8 inch) of stellite, stoodite, tube borium, tube haystellite, or some other composite rod of like type to serve as a hardened surface.
    Caution: Putting on the hardened surface is an application, not a fusion process. Do not let the base metal get too hot. Because of its extreme hardness, the surfacing material will not stand severe shock; therefore, be careful not to apply it too thickly (see pars. 221 to 226, incl., TM 9-2852).
    c.	If electric arc welding is the method chosen, proceed also as described in TM 9-2852 (pars. 221 to 226, inch). Use a stellite rod or equal.
    d.	Most of the tubular rollers and spacers are made of standard pipe or steel tubing. The sizes of these parts are included in the list of maintenance parts (par. 45). New rollers and spacers may be cut from pipe, if these parts are not available.
    e.	The towing cable (29), furnished as original equipment, is
    33
    a length of 1/2-inch 6x19 plow-steel wire rope, with 12-inch loops spliced on each end. The cable is 10 feet long over-all. Make replacement cables from usable ends of winch rope, 1/2 to 5/8 inch in diameter.
    42.	Replacing Point
    One 5/8x3-inch and one 5/8x4-inch No. 3 plow bolts are used to attach the point to the upper face of the landside. The point is provided with three holes. When new, use the two holes nearer the sharp end of the point. As the point wears away, move it forward one hole. The point always should project below the bottom of the landside. Replace the point when it is worn too short to do this. The bevel on the point is normally placed on the bottom. As it wears back, turn it over to obtain projection below the bottom of the landside. This also will aid penetration in hard soil.
    43.	Replacing Shin
    The shin (19) is attached between the standard gussets by one 5/8x3-inch bolt. The shin is reversible end for end, and can be changed by removing the bolt, lifting the shin until the lower end can be removed from the landside, and then pulling it diagonally down and out. The shin usually is self-sharpening. Replace it or build it up when its thickness has been reduced to about 1 1/8 inches.
    44.	Replacing Coulter Blade
    The coulter (28) turns on a tubular steel axle which is clamped rigidly in place by the coulter axle bolt. The coulter can be removed by taking out this bolt. The edge of the coulter blade will become rounded in use. It is not practicable to keep this edge sharp. If the blade becomes bent, straighten it if possible. If the blade breaks, or wears to less than 10 inches in diameter, replace it. For field replacement, replace the entire assembly (blade, hub, and bushing) rather than attempt to install a new blade in an old hub.
    34
    35
    SECTION V
    SUPPLEMENTARY DATA
    45. Maintenance Parts List
    Note. Order maintenance parts by stock number, name, and description.
    Reference	Signal Corps	M	,	...	Quantity	Lowest
    symbol	stock No	Name of part and description	per major	maintenance
    ‘____	•____________________________ unit	echelon
    6H2061........Plow LC-61 (Cable) ......................
    6H2061/A10....Arbor: steel; cold-finished, bonderized	....... 1.........Depot.
    24..........6H2061/A20....Axle Assembly: steel .......................... 1.........Depot.
    6H2061/B10....Bearing: axle; steel casting ........................ 4...Depot.
    6L612-3.1H....Bolt: hexagonal-head, machine; 3/4"	diameter, 3 1/8". 2...Depot.
    over-all length .......................
    29..........6Z1960........Cable: towing, plow; steel wire; 120" long, 1" diameter. 1.Depot.
    5..........6H2061/G25....Cable	Guide	Assembly:	center .................. 1.........Depot.
    1..........6H2061/G26....Cable	Guide	Assembly:	front ................... 1.........Depot.
    14..........6H2061/G27....Cable	Guide	Assembly:	rear .................... 1.........Depot.
    15..........6H2061/L1.....Cable	Guide	Latch Assembly .................... 1.........Depot.
    6Z7906........Rope RP-17: 1/2" diameter .................... 1..........Depot.
    6H2061/C2.....Cap: axle bearing; steel casting .............. 4...■.....Depot.
    39..........6H2061/R20....Coulter Control Rod and Lever Assembly ........ 1.........Depot.
    28..........6H2061/C20....Coulter and Wheel Assembly .................... 1.........Depot.
    Rsymboie	S'ftock No*™	Name of part and description	p^maicr	maintenance
    ‘	unit	echelon
    34..........6Z6012-14......Fastener: swivel, snap hook;	North	&	Judd, #16-1/2" . 1...Depot.
    6H2061/F10....Frame Assembly ................................. 1.........Depot.
    6Z3859........Fitting: hydraulic; Alemite,	#1610-1/4" ........ 4.........Depot.
    17..........6H2061/C10....Gate Chain Assembly ............................ 1.........Depot.
    35..........6H2061/F11.....Holding Frame Assembly ........................ 1.........Depot.
    27..........6H2061/H10.....Lifting Hook Assembly .......>................. 1..........Depot.
    6H2061/N25....Nut: hexagonal; 11/4"-12; Timken, #K-8110 ...... 2.........Depot.
    6L3962-47P....Pin: steel; 1" diameter, 2 15/16" long ......... 1.........Depot.
    54..........6H2061/F12.....Pivot Frame Assembly .......................... 1.........Depot.
    6H2061/P10....Plate: steel; hot-rolled; 5" x 2 1/2" x 5/8" ... 1.........Depot.
    6H2061/P11....Plate: hitch; steel casting .................... 1.........Depot.
    6H2061/P12....Plate: guide; steel; hot-rolled; 10"x3 1/4" .... 1.........Depot.
    43..........6H2061/S10....Reel Support Assembly .......................... 1.........Depot.
    3..........6H2061/S5......Sliding Bar and Adjusting Screw Assembly ...... 1.........Depot.
    6H2061/S20....Spacer:	steel;	1" of 3/4" standard black	pipe .. 1.........Depot.
    6H2061/S21....Spacer:	steel;	7/16" of 1/2" standard black	pipe . 2......Depot.
    6H2061/S30....Spring:	steel;	15" long, 11/2" diameter	..... 2.........Depot.
    6H2061ZS31....Spring:	steel;	10" long, 11/4" diameter	..... 1.........Depot.
    6H2061/S32....Spring:	steel;	11" long, 11/2" diameter	....... 2.......Depot.
    6H2061/B40....Spring Bracket Assembly ........................ 1.........Depot.
    36
    Reference	Signal Corps	XT f	,	...	Quantity	Lowest
    symbol	stock No.	Name of part and description	per major	maintenance
    »	_________________________ unit	echelon
    6H2061/C15....Spring Clip: steel; hot-rolled .......................... 1.Depot.
    18..........6H2061/S15.....Standard Assembly .............................. 1.........Depot.
    20..........6H2061/S16.....Step Assembly .................................. 2.........Depot.
    57..........6Z1042.........Talc Box M-401 ................................. 1.........Depot.
    52, 53,
    54, 55, and 56.....6H2061/B1.....Towing Bar Assembly ............................ 1..........Depot.
    34..........6H2061/L8......Trip Lever Assembly ........................... 1..........Depot.
    6L58004.......Washer: 11/4"; Timken, part #K-6135 ..................... 2.Depot.
    6H2061/W10....Wheel Assembly: rear  .......................... 2..........Depot.
    General Hardware
    6L608-1.5P....Bolt: machine; l/2"-13 x 11/2" long; square head, steel. 4..Depot.
    6L608-1-7P....Bolt:	machine;	l/2"-13	x 1 3/4" long;	square head,	steel. 2.Depot.
    6L608-2-2P....Bolt:	machine;	l/2"-13	x 2 1/4" long;	square head,	steel. 1.Depot.
    6L608-2.7P....Bolt:	machine;	l/2"-13	x 2 3/4" long;	square head,	steel. 1.Depot.
    6L610-1.7P....Bolt:	machine;	5/8"-ll	x 1 3/4" long;	square head,	steel. 2.Depot.
    6L610-2.5P....Bolt:	machine;	5/8"-ll	x 2 1/2" long;	square head,	steel. 4.Depot.
    6L610-2.7P....Bolt:	machine;	5/8"-ll	x 2 3/4" long;	square head,	steel. 2.Depot.
    6L612-1.7P....Bolt:	machine;	3/4"-10	x 1 3/4" long;	square head,	steel. 1.Depot.
    6L612-2P......Bolt: machine; 3/4"-10 x 2" long; square head, steel . 1....Depot.
    37
    Reference	Sieniil C