New Home NH60 Service Manual & Parts List

1

SERVICE MANUAL

&

PARTS LIST

MODEL: NH60

2

LOCATE AND IDENTIFY PARTS ..................................................................................................3

WIND THE BOBBIN ......................................................................................................................4

PREPARE YOUR TOP THREAD ...................................................................................................5

LCD DISPLAY ...............................................................................................................................6

WHAT TO DO WHEN ................................................................................................................ 7-9

CHANGING EXTERNAL PARTS

FACE COVER..............................................................................................................................10

FREE-ARM COVER ...................................................................................................................11

FRONT COVER .................................................................................................................... 12-13

REAR COVER ............................................................................................................................. 14

MECHANICAL ADJUSTMENT

PRESSER BAR HEIGHT ............................................................................................................15

NEEDLE DROP POSITION ........................................................................................................16

ADJUSTMENT OF HOOK TIMING .............................................................................................17

REPLACING HOOK ....................................................................................................................18

ADJUSTMENT OF NEEDLE BAR HEIGHT ................................................................................19

CLEARANCE BETWEEN NEEDLE AND TIP OF HOOK ROTARY ............................................20

FEED DOG HEIGHT ...................................................................................................................21

TOP TENSION ............................................................................................................................22

REPLACING THE ELECTRONIC COMPONENTS

CIRCUIT BOARD-A CONNECTION ...........................................................................................23

SELF-DIAGNOSTIC TEST .................................................................................................... 24-28

CIRCUIT BOARD-A .............................................................................................................. 29-30

DRIVING MOTOR .......................................................................................................................31

SWITCHING REGULATOR UNIT ................................................................................................32

ADJUSTING BUTTONHOLE LEVER POSITION ........................................................................33

PARTS LIST .......................................................................................................................... 34-47

INDEX

3

LOCATE AND IDENTIFY PARTS

NEEDLE CLAMP

NEEDLE

PRESSER

FOOT HOLDER

PRESSER FOOT

CARRYING HANDLE

HANDWHEEL

POWER SWITCH

MACHINE SOCKET

FREE ARM

PRESSER FOOT LIFTER

THREAD

TENSION DIAL

SPOOL PIN BOBBIN WINDER

SPINDLE

BOBBIN WINDER

STOPPER

VALUE SET BUTTONS

CURSOR BUTTONS

SPEED CONTROL SLIDER

NEEDLE POSITION UP/

DOWN BUTTON

AUTO-LOCK BUTTON

LCD DISPLAY

REVERSE STITCH BUTTON

START/STOP BUTTON

EXTENSION TABLE

NEEDLE PLATE

NEEDLE

THREADER

THREAD

CUTTER

FACE COVER

DROP FEED LEVER

FOOT CONTROL JACK

4

WIND THE BOBBIN

1. Hold the thread with both hands and pass the bobbin winding tension disc (1).

2. Pass the thread through the hole in the bobbin from the inside to the outside. Put the

bobbin on the bobbin winder spindle (2).

3. Push the bobbin winder spindle to the right.

4. Hold the free end of the thread in your hand and start the machine.

Stop the machine when the bobbin has been wound a few layers, and cut the thread close

to the bobbin.

5. Start the machine again. When the bobbin is fully wound, it will stop automatically.

Stop the machine and return the bobbin winder spindle to its original position by moving

it to the left, and cut the thread with a pair of scissors. Remove the bobbin from the

bobbin winder spindle.

10

1/8 3/8 5/8

2. Guide the thread into notch on the front

side of the bobbin holder. Draw the thread

to the left, sliding it between the tension

spring blades.

3. Continue to draw the thread lightly until

the thread slips into notch. Pull out

about 6˝ (15.0 cm) of thread.

1. Place a bobbin in the bobbin holder with

the thread running off counterclockwise.

4. Attach the hook cover plate. Check the

threading by referring to the diagram

shown on the hook cover plate.

(1)

(2)

5

PREPARE YOUR TOP THREAD

* Raise the thread take-up lever to its highest position by turning the handwheel

counterclockwise.

* Raise the presser foot lifter.

* Place a spool on the spool pin, with the thread coming off the back of spool.

1. Draw the end of the thread around the

upper thread guide.

2. While holding the thread near the spool,

draw the end of the thread down around

the check spring holder.

3. Firmly draw the thread up from right to

left over the take-up lever, and down into

the take-up lever eye.

4. Draw the thread through the thread guide.

Slide the thread behind the needle bar thread

guide on the left.

5. Thread the needle from front to back, or use a

needle threader.

1

3

2

5

4

6

LCD DISPLAY

The LCD display shows the following information when the machine is turned on.

q

STITCH PATTERN NUMBER

w CURSORS

e STITCH WIDTH

r STITCH LENGTH

z Press the cursor key to move the cursor under the stitch pattern number.

The cursors appear under both digits when turning the power on.

x Press the value set keys to change the stitch pattern number until the

pattern number of the desired stitch is indicated.

The number will increase or decrease by 1 each time you press the value set key.

c Press the key to move the cursor under the tens digit of the stitch pattern number.

The number will increase or decrease by 10 each time you press the value set key.

q

we r

z

x

c

7

CONDITION CAUSE HOW TO FIX REFERENCE

1. SKIPPING

STITCHES

2. FABRIC

NOT

MOVING

1. Needle is not inserted

properly.

2. Needle is bent or worn.

3. Incorrectly threaded.

4. Needle or thread are

inappropriate for the

fabric being sewn.

5. Sewing on

stretch fabric.

6. Inappropriate needle

bar height.

7. Inappropriate needle to

hook timing.

8. Inappropriate needle to

hook clearance.

9. Hook is damaged or too

worn.

1. Incorrect feed dog

height.

2. Feed dog is in down

position.

3. Thread on bottom side of

fabric is jammed up.

4. Feed dog teeth are worn.

Insert the needle properly.

Change the needle.

Rethread.

Use the recommended sewing

needle and thread.

Use a HA x #11 blue tip needle.

See mechanical adjustment “Needle

bar height”.

See mechanical adjustment

“Adjustment of hook timing”.

See mechanical adjustment

“Clearance between needle and tip

of the rotary hook”.

See mechanical adjustment

“Replacing hook”.

Adjust the presser bar level to make

the pressure stronger.

See mechanical adjustment “Feed

dog height”.

Raise the feed dog.

Make sure to bring both needle and

bobbin threads under the foot when

start sewing.

Change the feed dog.

P. 1 9

P. 1 7

P. 2 0

P.18

P. 2 1

WHAT TO DO WHEN

8

CONDITION CAUSE HOW TO FIX REFERENCE

3. BREAKING

UPPER

THREAD.

4. BREAKING

BOBBIN

THREAD.

5. NEEDLE

BREAKS

1. Initial sewing speed is

too fast.

2. Thread path is incorrect.

3. Needle is bent or dull.

4. Top tension is too strong.

5. Needle size is

inappropriate for fabric.

6. Needle eye is worn.

7. Needle hole in needle

plate is worn or burred.

1. Bobbin holder is

incorrectly threaded.

2. Too much thread is wound

on the bobbin.

3. Lint is stuck inside the

bobbin holder.

4. Thread quality is too low.

5. Thread is jamming around

the bobbin holder.

1. Needle is hitting the

needle plate.

2. Needle is bent or worn.

3. Needle is hitting the hook.

4. Fabric is being pulled

too strongly while sewing.

Start with medium speed.

Use the proper thread path.

Replace with a new needle.

Adjust top tension correctly.

Use appropriate needle for fabric

and thread in use.

Change the needle.

Repair the hole or replace the

needle plate.

See mechanical adjustment

“Needle drop position”.

Change the needle.

See mechanical adjustment

“Clearance between needle and

tip of the rotary hook”.

Guide the fabric gently while

sewing.

P. 1 6

P. 2 0

9

Eliminate the backlash.

Eliminate the looseness.

See part removal and

replacement “Driving motor (DC

motor)”.

Oil all moving parts.

Eliminate the looseness.

See mechanical

adjustment “Replacing hook”.

Adjust the feed balancing screw.

See mechanical adjustment

“Top tension”.

CONDITION CAUSE HOW TO FIX REFERENCE

6. NOISY

OPERATION

7. DEFORMATION

PATTERN

1. Backlash between hook

gear and lower shaft

gear is too great.

2. Lower shaft gear is loose.

3. Inappropriate belt

tension.

4. Not enough oil.

5. Upper shaft gear is loose.

6. Hook is damaged or too

worn.

1. Inappropriate feed

balance.

2. Top tension is too strong.

P. 3 1

P.18

P. 2 2

10

CHANGING EXTERNAL PARTS

FACE COVER

TO REMOVE:

1. Loosen the setscrew (1) and lift the face cover to disengage the rib on the inside.

Remove the face cover (2).

TO ATTACH:

2. Follow the above procedures in reverse.

(1)

(2)

11

CHANGING EXTERNAL PARTS

FREE-ARM COVER

TO REMOVE:

1. Loosen the setscrew (1) and (2). Move the free-arm cover (3) to the left. remove the

free-arm cover.

TO ATTACH:

2. Follow the above procedures in reverse.

(1)

(3)

(2)

12

Thread tension unit

CHANGING EXTERNAL PARTS

FRONT COVER (1)

TO REMOVE:

1. Remove the face cover and free-arm cover (see page 8 and 9).

2. Remove the setscrews (1) (2 pcs.).

3. Remove the setscrews (2) (5 pcs.), back cover (3) .

4. Remove the setscrews (4) (2 pcs.).

5. Loosen the setscrew (5).

6. Disconnect all the connectors from the circuit board A.

NOTE:

Do not disconnect the connectors by pulling on cord.

To disconnect, grasp the connector, not the cord.

TO ATTACH:

7. Follow the above procedures in reverse.

(1)

(3)

(2)

(2)(2)

(4) (4)

(5)

13

CHANGING EXTERNAL PARTS

FRONT COVER (2)

1. Disengage the front cover and rear cover hooks.

2. Remove the front cover.

TO ATTACH:

3. Follow the above procedures in reverse.

14

Back cover

Rear cover

CHANGING EXTERNAL PARTS

REAR COVER

TO REMOVE:

1. Remove the face cover and free-arm cover (see page 8 and 9).

2. Remove the setscrews (A) (4 pcs.).

3. Remove the setscrews (B) (5 pcs.) and back cover.

4. Remove the setscrews (C) (2 pcs.). Remove the rear cover.

TO ATTACH:

5. Follow the above procedures in reverse.

Setscrews (A)

Setscrews (B)

Setscrews (C)

15

MECHANICAL ADJUSTMENT

PRESSER BAR HEIGHT

The distance between the bottom of the presser foot in up position and the needle plate should be 6.0

mm.

1. Remove the face plate and needle.

2. Lower the feed dog below the needle plate. Place a block 6 mm thick under the presser foot and

lower the presser foot lifter (1).

3. Loosen the setscrew (2). Raise the presser foot lifter and tighten the setscrew (1) ﬁrmly.

Attach the needle and face plate.

NOTE:

Make sure that the presser foot should be parallel to the feed dog slots (3) in the needle plate.

Presser foot should be parallel

to the feed dog slots.

6.0 mm

(1)

(2)

(3)

16

MECHANICAL ADJUSTMENT

NEEDLE DROP POSITION

Set the stitch pattern to “ ”. The standard needle drop position should be at center of the needle

plate hole (1). Select zigzag stitch “ ”, and set the stitch width at “5.0”. The clearance between the

needle and the edge of the needle hole in the needle plate should be at least 0.2 mm on either side.

If not, adjust as follows:

1. Turn the power switch off. Remove the face cover. (see page 10.)

2. Loosen the hexagonal socket screw 3 x 4 (2). Adjust the needle drop position by turning the

eccentric pin.

3. Attach the face cover.

4. The direction of eccentric pin should be as shown in Fig. 1.

NOTE:

Check the hook timing after this adjustment.

0.2 mm

or more

0.2 mm

or more

A=B

Fig. 1

(1)

(2)

17

MECHANICAL ADJUSTMENT

ADJUSTMENT OF HOOk TIMING

MACHINE SETTING:

1. Remove the free-arm cover.

2. Select Pattern: No.00 (straight stitch)

3. Turn the power switch off.

TO ADJUST:

1. Remove the needle, presser foot, needle plate (A) and bobbin holder (B).

2. Insert the radial timing gauge (C) so that the small ﬁnger on the gauge ﬁts into the slot near the tip

of the hook.

3. Put the test pin (D) in the needle clamp. * Push it up until it stops.

4. Tighten the needle clamp screw (E).

5. Loosen the 2 screws (F) in the lower shaft gear (G).

6. Hold the handwheel so that the test pin (D) will not move, and turn the lower shaft gear (G) until

the test pin (D) comes in be tween the two white lines of gauge (C).

7. Tighten 2 screws (F).

8. Attach the bobbin holder, needle plate, presser foot and needle.

9. Attach the bed cover and base cover.

(A)

(B)

A

C

B

(C)

(D) (E)

(G)

(F)

18

Hook

(B)

(D)

(E)

(D)

(F)

Needle plate setscrew

Needle plate

Bobbin holder

(A)

Hook (C)

Marks

Right edge of feed dog teeth

Hook point

MECHANICAL ADJUSTMENT

REPLACING HOOk

If the hook point is damaged or too worn, the hook needs to be replaced.

TO REMOVE:

1. Remove the needle plate and bobbin holder.

2. Remove the front cover (see page 12 and 13).

3. Turn the handwheel toward you to align the hook point and the right edge of feed dog teeth.

4. Mark both the handwheel and the rear cover to indicate where the hook point and the right edge of

feed dog teeth meets.

5. Loosen the setscrew (A).

6. Push the hook shaft(B) from the hole (C) with allen screwdriver. Remove the shaft, washers (D),

(E) and (F). * Washers (D) are transparent. washer (E) has a projection on its edge.

Insert the projection in the groove of the gear when attaching.

7. Remove the hook from the hook race. do not remove the feed dog teeth when removing it.

TO ATTACH:

8. Reverse the procedure above. align the hook point and the right edge of feed dog teeth when

attaching the hook to the hook race. (Match the marks on the handwheel and rear cover. Wipe out

the marks after this attachment.)

9. Check the hook timing (see page 17) after the replacement.

If necessary, adjust the hook timing.

19

(F)

(A)

(B)

(C)

(E)

(G)

(D)

(I)

(H)

(J)

(C)

MECHANICAL ADJUSTMENT

ADJUSTMENT OF NEEDLE BAR HEIGHT

NEEDLE BAR HEIGHT

MACHINE SETTING:

1. Remove the face cover. (See page 10)

2. Select Pattern: No.00 (straight stitch).

3. Turn the power switch off.

TO ADJUST:

1. Remove the needle, presser foot, needle plate (A) and bobbin holder (B).

2. Insert the radial timing gauge (C) so that the small ﬁnger on the gauge ﬁts into the slot near the tip

of the hook.

3. Attach the needle bar height gauge (D). * Push it up until it stops.

4. Tighten the needle clamp screw (E).

5. Loosen the screw (F) on the needle bar holder.

6. Turn the handwheel toward you until the needle bar reaches its lowest position.

7. Move the needle to adjust the position of the needle bar so that the face (G) touches the side of

pin (H) and the end of pin (I) touches the surface (J) of gauge (C).

8. Tighten the screw (F) securely.

9. Attach the bobbin holder, needle plate, presser foot and the needle.

20

MECHANICAL ADJUSTMENT

CLEARANCE BETWEEN NEEDLE AND TIP OF THE ROTARY

HOOk

* The clearance between the needle and the point of hook should be –0.1 to +0.05 mm.

ADJUSTMENT PROCEDURE:

1. Remove the needle plate and bobbin holder. Attach the master needle. Turn the power switch on

and set the zigzag width at maximum.

2. Remove the face cover.

3. Loosen the setscrew (A) (2 pcs.).

4. Turn the handwheel toward you. Adjust the clearance between the needle and the tip of the rotary

hook, by moving the hook base plate up or down, to within –0.1 to +0.05 mm at the left and right

needle position.

5. Tighten the setscrew (A) (2 pcs.).

6. Attach the face cover. Remove the master needle. Attach the bobbin holder and

needle pate.

7. Check the clearance between the needle and the edge of the needle hole in the

needle plate (see page 16).

Tip of hook

–0.1 to +0.05 mm

Needle bar supporter

adjusting plate

Hexagonal socket screw

(A)

Needle plate

Bobbin holder

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New Home NH60 Service Manual & Parts List

New Home NH60 Service Manual & Parts List

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