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Double needle lock stitch machine:

1) Brand and make:a) Manufacturer of this machine is Brother.b)

The model No. of this machine is LT2-B845-3

2) Machine bed:a) Size of the machine is [40(l) * 19(b) * 10.5(h)] inch.b) The machine bed is flat bedc) Dimensions from the needle(bed)= (510*180)mm

3) Right-395mm, left-115mm, back-90mm, front-90mm, upright-270mm, underarm-295mm.

4) Head pulleya) The diameter of the head pulley is 105mm.b) The direction of rotation of head pulley is towards the operator i.e. anticlockwise.c) It is situated to right side of the machine.d) The v-belt pulley cover is a safety feature of the head pulley.

5) Stitcha) The stitch type is lockstitchb) Stitch number is 301*2c) Stitch mechanism is interlacing.

6) Needlea) There are two needles in this machine.b) The type of the needle is DP*5#14.c) Mounting mechanism: The needle is attached into the needle clamp and is

tightened with screw.

d) Since it is a double needle lockstitch machine, there are two needle clampse) The position of the needle on either side is opposite to each other.f) The scarf position of the right needle is at 3 oclock and scarf position of the left

needle is at 9 oclock.

g) The needle point is regular round point(FST-301)7) Bobbin:

a) Assembly: Consists of bobbin, bobbin case and rotary hook.b) Movement of the bobbin is in the clockwise direction

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c) There are two bobbins in this machine which are placed below the flat bed oneither sides of the throat plate and they are visible through the two circular gaps

(BOBBIN WINDOWS) seen on either sides of the throat plate.

8) Threading sequence:a) Needle threading sequence: the thread is passed in the following sequence;

thread stand- thread guide- stud screw- cylindrical rod- tension spring- metal

tension disk- check spring- thread take-up two thread guides-needle eye.

b) Bobbin threading sequence: the bobbin is inserted in rotary hook and thread ispassed through slot under the tension spring. The thread is passed through the

needle plate and 50mm (approx.) thread is pulled out.

9) Tension devices:a) The tension devices in a double needle lockstitch machine consists of tension

disk, spring and stud screw.

b) The tension devices are attached on the mid-left of the machine.c) The check springs in the tension devices are mainly essential for regulating the

thread tension with help of screw.

10)Take up lever:a) The take-up lever consists of thread take-up which assists the thread in an

oscillating motion.

11)Throat plate:a) The throat plate is fixed with help of two screws on the flat bedb) It is situated below the pressure foot.

12)Feeding mechanism:a) Feed dog:

i. Feed dog is situated below the throat plate and is attached to the rockershaft which controls its elliptical movement.

ii. There are two numbers of rows and there are 16 teeth in the feed dog.iii. The pitch is 1mm.

b) Presser foot:i. It is a standard presser foot.

ii. The presser foot is attached with the presser bar.iii. The presser foot is used for applying optimum amount of pressure on the

fabric depending upon the type of fabric which can be adjusted with help

of presser foot adjustment screw.

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iv. The presser foot can be manually lifted with help of hand lever situatedbehind the presser bar bush.

v. Also presser foot can be lifted with help of knee lifter situated below themachine bed.

c) Needle movement is elliptical.13)Stitch regulator:

a) The stitch regulator is situated on the right side of machine, on the left of backtack lever.

b) Stitch regulator, as the name suggests regulates the number of stitches.c) There are 5 divisions on the stitch regulator.

14)Lubrication:a) The oil manufacturer is Juki.b) The oil number of oil used in double needle lockstitch machine for lubrication is

New Defrix No.1.

c) Type of lubrication: minimum lubrication.

DNLS:

A double needle lockstitch machine works on the same principle as the single needle

lockstitch machine while using two needles and two bobbins thus resulting in two parallel

rows of lockstitch. The distance between two stitches depends upon the distance between

the two needles on the needle bar which can be adjusted. In our machine the distance

between two stitches is inch.

Stitch formed appears as:

When the stitch forms correctly equal amounts of bobbin and needle thread are used.

Needle thread can exceed up to 10%. Upper and lower threads interlock in the centre of the

fabric. LT2-B845-3 Model is used for stitching thin and thick material.

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The double needle lockstitch machine consists of clutch motor. The machines motor is

especially designed with powerful performance for industrial sewing machines purpose.

Vibration and noise are minimal. The temperature rising of the motor is extremely low.

The double needle lockstitch machine is mainly used for box pockets, top stitch front collar

edges, box pocket pleats, topstitch the collars, cuffs, inseam of trousers. The double needle

lockstitch machine is the tightest and most secure stitch which makes it a good choice for

stitching the in seams of the trousers.