hobbylock 783 - Sewing machine PFAFF - Free user manual and instructions

USER MANUAL hobbylock 783 PFAFF

Line drawing of a sewing machine with no visible text or symbols

Notes on safety

A) Owing to the up and down movement of the needle and the upper knife, the user must take sufficient care to avoid injury and observe the sewing area continuously while sewing.

B) When leaving the machine, changing parts or accessories, the machine must be disconnected from the power source.

C) The maximum approved wattage of the light bulb is 15 watts.
D) The drive belt must never be adjusted by anyone but an authorized Pfaff agent.

Contents

Parts of the sewing machine 2,3

Electrical connection 4

Master switch and sewing light 4

Foot control 5

Notes on safety 5

Installing the thread spool stand 6

Opening the looper cover 7

Threading guide wires and the thread guides behind the carrying handle 7

Threading the right looper 8

Threading the left looper 9

Threading the needle 10

Thread reel change on threaded machine 10

Inserting the lint box 11

Seam allowance 11

Sewing test 12

Points to observe during sewing 13

Securing the seam 14

Axial blocking of the upper knife 14

Setting the standard thread tensions 15

Correcting the thread tensions 16

Thread chart for 3-thread overedge seam 17

Setting the stitch length 17

Disengaging the upper knife 18

Adjusting the seam width 18

Changing the sewing foot 19

Rolled hems 20,21

Changing the needle 22

Changing the knives 22

Changing the upper knife 23

Changing the lower knife 24

Changing the light bulb 25

Cleaning the thread tensions 25

Oiling the machine 26

Sewing problems and their removal 27

Accessories 28

Thread spool net/thread unreeling disc 28

Specifications 29

Contents of the cardboard box 29

Technical diagram of a sewing machine with numbered parts for identification

22 16 9 21 20

25 37 24 23 27 26 38

Parts of the sewing machine

1 Thread spool stand
2 Carrying handle
3 Needle thread tension dial
4 Housing cover
5 Right looper thread tension dial
6 Left looper thread tension dial
7 Thread tension cover
8 Lint box
9 Handwheel
0 Looper cover with recess
11 Upper knife
12 Work support (swivel-type)
13 Needle plate
14 Sewing foot
15 Needle bar
16 Sewing foot lifting lever
17 Thread spool holder
18 Thread guides
19 Thread guide bar
20 Machine socket
21 Master switch
22 Rear thread guide (4 x)
23 Feet
24 Accessory box
25 Stitch length adjustment knob
26 Seam width adjustment knob
27 Rotary lever for upper knife
disengagement
28 Foot control
29 Foot control plug for machine socket
30 Mains plug
31 Right looper
32 Left looper
33 Lower knife
34 Lower knife retaining screw
35 Retaining screw of upper knife
36 Thread spool centering piece
37 Accessories retainer
38 Retaining screw for blocking the upper knife

Technical line drawing of a mechanical component with labeled part '8' (no text or symbols beyond label)

30 28 29

11 33 34 31 32 35

Line drawing of a computer interface with an attached plug and cable (no text or symbols)

Electrical connection

Use this machine only on a flat surface or on a special sewing table.

Connecting the foot control:

Insert the plug of the control in the machine socket. Then connect the mains plug to a power source.

Caution: When the machine is not in use, switch it off at the master switch and disconnect the plug from the power source. Do not place any objects on the foot control.

Line drawing showing two views of a computer monitor with a left-side control knob (no text or symbols)

Switching the machine ON and OFF

Power and sewing light are switched on and off simultaneously with master switch 12.

Switching on:

Press switch. Machine and sewing light are switched on.

Switching off:

Press switch again. Machine and sewing light are switched off.

Technical diagram showing a device with labeled ports and directional arrows, including a play button icon.

Foot control

The speed of the Hobbylock is regulated as follows:

The more you press the foot control down, the faster the machine will sew.

Electronic foot control

Maximum speed can be pre-selected in two steps by the switch on the foot control.

Position ▶ = Half speed Position ◀◀ = Full speed

Notes on safety

A) Owing to the up and down movement of the needle and the upper knife, the user must take sufficient care to avoid injury and observe the sewing area continuously while sewing.
B) When leaving the machine, changing parts or accessories, the machine must be disconnected from the power source.
C) The maximum approved wattage of the light bulb is 15 watts.
D) The drive belt must never be adjusted by anyone but an authorized Pfaff agent.

Technical diagram showing five steps of a sewing machine operation with labeled parts A and B, including hand positioning and tool path.

Installing the thread spool stand

Loosen clamp screw A a little and pull washer up to the screw head. Insert thread spool stand 1 from the top.

Tighten clamp screw A securely

Insert four thread spool holders 17 with centering pieces 36 fully in the holes of the thread spool stand.

Push thread guiding part 18 into guide bar 19.

Pull up guide bar and align it so that thread guides 18 are exactly above the spool holders.

Technical line drawings of mechanical components and assembly (no text or symbols)

Opening and closing looper cover and work support

Push looper cover fully to the right, hold it, and swing it down.

To close the looper cover, push it up until it locks.

To open work support 12, push it to the left. To close the work support, push it to the right until it locks.

A threading diagram is fixed to the machine behind the looper cover. This diagram shows the different threading paths by different colors (see Fig. A).

Technical line drawings of mechanical components labeled B and C, showing assembly or assembly steps without any text or symbols.

Threading the guide wire of the thread spool stand and the thread guides behind the carrying handle

The machine must be threaded correctly. First pull the respective threads through their corresponding guides (Figs. B and C).

Then thread the tensions in the following sequence:

1. right looper (red)
2. left looper (yellow)
3. needle (blue)

Figure B shows the threading path of the individual threads for thread guides 18. For threading the guides behind carrying handle 2, the handle must be pulled up (Fig. C).

After threading carrying handle 2 must be pushed down again.

Technical diagram of a sewing machine with numbered components and labeled parts

Threading the right looper:

Thread the right looper in sequence 1 to 8 and pull approximately 10 cm (4") of thread through the looper eye (the thread path is marked red).

important.

In order to obtain perfect sewing results, the thread must be pulled between the tension discs when threading the tensions.

Technical diagram of a mechanical assembly with numbered components for identification

Technical diagram of a sewing machine with numbered components for identification

Threading the left looper:
Insert the left looper thread in sequence 1 to 9 and pull approximately 10 cm (4") of thread through the looper eye (the thread path is marked yellow).

Technical diagram of a mechanical assembly with numbered components and labeled parts

Technical diagram of a sewing machine with numbered components for identification

Threading the needle

Threading of guide wires 18 and of the thread guide behind the carrying handle is shown on page 7.

In the left-hand illustration the threading path is shown from the blue tension (1) up to the right needle (6). At point 5 the thread must be pulled behind the thread retainer.

Line drawing of a sewing machine with no visible text or symbols

After threading the machine, push handle 2 down, and close work support 12 and looper cover 10.

Thread spool change on threaded machine

Cut the threads close to the thread spool. Place new thread spools on spool holders 17. Tie the threads still in the machine and the new threads together. Pull the needle thread out of the needle. Now pull at the thread ends until the knots are about 15 cm past the last thread guide before the needles. Cut the knots off and pull the threads through the respective needle eyes. The looper threads can be pulled until past the looper eyes without interruption. Pull about 10 cm of thread through the looper eye.

Line drawing of a sewing machine with a sewing machine base and a hand operating it (no text or symbols)

Inserting the lint box:

Insert the two tabs of the lint box downwards in the recess of the looper cover. Then push the bottom of the box against the machine

For removal of the lint box, use the reverse order.

Line drawing of a sewing machine needle and foot (no text or symbols)

Seam allowance

If the cutting is guided along below marking N on the looper cover, a seam allowance of 16 mm must be taken into consideration when cutting the fabric.

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Sewing test

After threading, a sewing test test should be made.

Raise sewing foot lever 16, as shown in the illustration

Line drawing of a sewing machine needle stitching fabric (no text or symbols)

Insert test fabric up to the upper knife and lower the sewing foot.

Line drawing of a hand operating a sewing machine needle (no text or symbols)

Hold thread ends with your left hand while turning hand wheel with your right hand in the direction indicated by the arrow on the wheel. Lay the threads back under the sewing foot. Make sure that threads have interlocked correctly.

Line drawing of a sewing machine needle stitching fabric (no text or symbols)

Points to observe during sewing

Place the fabric completely under the sewing foot when starting to sew. (Also after the machine has been rethreaded)

Sew the first stitches slowly.

Since the fabric is fed automatically do not pull or push the fabric. Use your hand for guiding only.

Technical line drawing showing two views of a sewing machine needle and fabric work (no text or symbols)

Sew approximately 5 cm beyond the end of the seam and use a scissors to cut the thread chain.

Securing the seam:

Knot the thread chain. For knit fabrics, a crochet needle can be used to pull the thread chain into the seam

Or:

Sew about 5 cm (2") beyond the end of seam. Then turn the workpiece around and sew a few stitches over the seam just sewn without cutting the thread chain.

Blocking the upper knife

Sewing very thick fabrics and workpieces with different thicknesses:

On this machine, all kinds of fabric from extremely thin to extremely thick can be processed. When sewing extremely thick fabrics or workpieces with different thicknesses, the screw of the upper knife must be tightened, as shown in the illustration.

By tightening the screw, axial movement of the upper knife is inhibited.

Note:

When sewing thin or medium fabrics, the screw of the upper knife holder must be loosened by about 2 turns, so that the upper knife can move axially.

Technical line drawing of a mechanical assembly with a tool and component (no text or symbols)

Reverse side Left looper thread Right looper thread Needle Top side

Setting the standard thread tension N

The thread tension to be set depends on the fabric type and thread size used. Set the N on the thread tension dials opposite the front edge of thread tension cover 7 (see illustration below).

Make the correct adjustment after examination of the interlocking of threads (the illustration on the left shows a correct seam)

Page 16 lists examples for correction of the individual thread tensions.

Line drawing of a sewing machine with two circular buttons and handle (no text or symbols)

Correcting the thread tensions

When the thread tension is turned in (+) direction, the tension is increased. When turned in (-) direction it is decreased.

The needle thread A is too loose (blue thread tension)

The right looper thread C is too loose (red thread tension) or the left looper thread D too tight (yellow thread tension).

The left looper thread D is too loose (yellow thread tension) or the right looper thread C too tight (red thread tension).

Thread chart for 3-thread overedge seam

Material	Thread		Stitch length
Light materials:
Organdy, light knit fabric, Taffeta, silk, lining materials	Cotton	No. 80-100	20 to 40 mm
	Silk	No. 80-100
	Synthetic thread	No. 70-140
Medium-heavy materials:
Cotton, tricot, linen, dress materials	Cotton	No. 60-100	20 to 40 mm
	Silk	No. 50-100
	Synthetic thread	No. 70-140
Heavy materials:
Tweed, suit materials, denim, heavy cloth	Cotton	No. 40-60	20 to 50 mm
	Silk	No. 40-60
	Synthetic thread	No. 70-140
Knit fabrics:
Rolled hem	Cotton	No. 40-60	20 to 50 mm
	Silk	No. 40-60
	Synthetic thread	No. 70-140
	Polyester thread	No. 120-140	1.0 to 2.0 mm
	Mercerized thread (bulk thread)

Technical line drawing of a mechanical assembly with no visible text or symbols

Setting the stitch length

Open work support 12. Hold hand wheel 9 fast and set stitch-length adjustment knob 25 at the stitch length desired between 1 and 5 mm. Standard setting N is 3 mm.

Illustration of a person using a camera and a device, showing motion phases (no text or symbols)

Disengaging the upper knife

Remove lint box 8. Open work support 12 and looper cover 10 If necessary, loosen screw 38 for axial upper knife blocking

Push rotary lever 27 of the axial upper knife guide fully to the right, hold it, and turn it forwards until pin A engages in the hole of the knife. Now the upper knife is disengaged.

Line drawing of a hand operating a mechanical device with no visible text or symbols

Adjusting the seam width

The standard seam width setting is marked with N (3.5 mm).

Disengage the upper knife according to the above description.

The desired seam width is set with adjusting knob 26. The scale on the seam-width adjustment knob ranges from 3 to 5.

Set the upper knife at its basic position again and close the looper cover.

When processing thick fabrics, securely tighten screw 38 for blocking the upper knife, see page 14.

Sew a test seam

Note:

After adjusting the seam width, it may be necessary to re-adjust the thread tension.

F H G

Changing the sewing foot

Raise sewing foot lifting lever 16.

Disengage the sewing foot by pressing lever F

Engage the sewing foot.

Place the sewing foot under the sewing foot holder so that when you lower the sewing foot lifting lever, crosspiece G of the foot engages in groove H of the sewing foot holder.

The illustration on the left shows a correctly engaged sewing foot.

Top side Reverse side 1

Rolled hem

sewn with polyester thread 120-140

A rolled hem is used for light, delicate fabrics and is an attractive finish for open edges. Without any effort you can sew professional rolled hems on neck scarves, shawls and valances (see page 21).

Top side Reverse side 2

Rolled hem with polyester thread

Preparation of the sewing machine:

Needle insert needle

Sewing foot. engage rolled hem foot "R

Seam width. from 30 to 40 mm (depending on material)

Stitch length: from 10 to 20 (short stitch length)

Thread: polyester thread 120-140 for blue, red and yellow thread tensions

Threading path:

1	right looper, red path	polyester thread
2	left looper, yellow path	polyester thread
3	needle thread, blue path	polyester thread

For threading of needle and loopers, see pages 7 to 11

Tension setting: round edge, Fig. 1 flat edge, Fig. 2

Red thread tension, right looper	approx. "N"	approx. +5
Yellow thread tension, left looper	+5	approx. "N" to -1
Blue thread tension, needle thread	approx. "N"	approx. "N" to +1

Depending on material and thread, the respective thread tension must be set higher or lower

Rolled hem, sewn with bulk thread:

This hem requires three threads, one bulk thread and two polyester threads 120-140

Preparation of the machine, as described above.

Thread: bulk thread - red tension polyester thread 120-140 for blue and yellow tensions

Threading path:

1. right looper, red path	bulk thread
2. left looper, yellow path	polyester thread 120-140
3. needle thread, blue path	polyester thread 120-140

For threading of needle and loopers, see pages 7 to 11

Tension setting:	round edge, Fig. 1	flat edge, Fig. 2
Red thread tension, right looper	approx. "N" to -3	approx. "N" to +5
Yellow thread tension, left looper	approx. +5	approx. "N"
Blue thread tension, needle thread	approx. "N"	approx. "N"

Note:

Rolled hems can also be sewn with two bulk threads and one polyester thread. The bulk threads must then be threaded in the left and right looper

Depending on material and thread, the respective thread tension must be set higher or lower.

Pure mechanical diagram showing a lever mechanism with rotational arrows, no text or symbols present

K L M

Changing the needle

Pull out the mains plug. Lower the sewing foot. Turn the hand wheel in the direction of the arrow until the needle bar is at its highest position. Use the needle change tool from the accessories (see p. 31, item 11) as follows: Insert the needle in hole M of the needle change tool. Loosen the set screw of the needle with the screw driver. Remove the needle by pulling it downwards.

Inserting the needle

Insert the needle in hole M of the needle change tool in such a way that flat side K of the needle shank faces surface L of the needle change tool. Then push the needle up into the needle holder as far as it will go. Tighten needle set screw securely. Remove needle change tool from the needle.

Notes:

The following needles are used on these machines: System 130/705 H (75-90) Although the correct needle size depends on the material and the thread size used, we recommend needle size 75-90. An incorrectly inserted needle will cause thread breakage and skipped stitches.

Line drawing of a hand holding a small object with a labeled arrow (no text or symbols present)

Changing the knives

Knives are available as spare parts.

Pull out the mains plug

Disengage the upper knife, see page 18.

Simple line drawing of a person standing near a vehicle, possibly a robot or robotic arm (no text or symbols)

Changing the upper knife:

Pull out the mains plug.

Unscrew knife retaining screw 35 and remove upper knife

Line drawing of a hand operating a mechanical device with a tool (no text or symbols visible)

Insert the new upper knife and tighten its retaining screw securely.

Pure mechanical component diagram without any text, numbers, or symbols

Set upper knife with knife guide 27 up (cutting position). Turn the handwheel until the upper knife is at its lowest position.

In this position, the front edge of the upper knife must be 0.5 to 1 mm below the needle plate surface.

Technical line drawing of a mechanical clamp or bracket assembly (no text or symbols)

Changing the lower knife

Pull out the mains plug!

Disengage the upper knife (see page 18). Remove retaining screw 34 of the lower knife.

Line drawing of a hand holding a metal bracket with mounting holes (no text or symbols)

Place the new lower knife against the left guide of the lower knife holder and push it up, as shown in the illustration. Replace the screw with the pressure plate.

Technical line drawing of a mechanical clamp or bracket assembly (no text or symbols)

Align the cutting edge of the lower knife so that it is flush with the needle plate surface.

Before tightening the retaining screw, align the pressure plate. Reset the upper knife to cutting position.

Simple line drawing of a hand holding a small object, possibly a tool or device, with no visible text or symbols.

Changing the light bulb:

Pull out the mains plug.

Loosen housing cover retaining screw 4

Open the housing cover.

Behind it, the light bulb of the sewing light is situated

Sketch of a person standing near a vehicle, possibly a robot or robotic arm, with no visible text or symbols.

Removing the light bulb:

Push the light bulb upwards and turn it fully to the left

Inserting the light bulb:

Insert the new bulb (15 Watt max.) with the pins in the slots, push it up and turn it fully to the right.

Close and fasten housing cover.

Simple line drawing of a desk with a chair and a pen, no text or symbols present

Cleaning the thread tensions:

Pull thread tension cover 7 with both hands to the front (direction of arrow) and remove it.

Technical diagram showing a hand operating a mechanical device with labeled component A and internal components

Use the brush provided with the accessories to remove dust and lint from between the tensions.

Replace the thread tension cover by engaging the tabs of the cover in retainers A of the housing.

Oiling the machine:

Every time before you take the machine into operation, you should apply a little oil to the places indicated. The bushings and other important moving parts are made of special material and need to be oiled only once or twice a month. One to two drops of high quality sewing machine oil are sufficient for oiling.

Technical line drawing of a mechanical device with no visible text or symbols

Technical line drawing of a mechanical clamp or bracket with two circular holes and a droplet symbol (no text or labels)

Technical line drawing of a mechanical assembly (no text or symbols)

2.1. 3.1. 4.1. 5.1. 6.1. 7.1. 8.1. 9.1. 10.1. 11.1. 12.1. 13.1. 14.1. 15.1. 16.1. 17.1. 18.1. 19.1. 20.1. 21.1. 22.1. 23.1. 24.1. 25.1. 26.1. 27.1. 28.1. 29.1. 30.1. 31.1. 32.1. 33.1. 34.1. 35.1. 36.1. 37.1. 38.1. 39.1. 40.1. 41.1. 42.1. 43.1. 44.1. 45.1. 46.1. 47.1. 48.1. 49.1. 50.1. 51.1. 52.1. 53.1. 54.1. 55.1. 56.1. 57.1. 58.1. 59.1. 60.1. 61.1. 62.1. 63.1. 64.1. 65.1. 66.1. 67.1. 68.1. 69.1. 70.1. 71.1. 72.1. 73.1. 74.1. 75.1. 76.1. 77.1. 78.1. 79.1. 80.1.

these machines have been developed for easy operation, and there are no difficult adjustments to be made. Sewing problems of the kind described below may occur due to minor adjustment- and peration errors. They can easily be corrected by following the instructions below.

Problem	Cause	Solution
Needle breakage	Needle bent or point damaged	Insert new needle
	Needle not fully inserted	Insert new needle correctly (see page 22)
	Material pulled	Do not pull material during sewing
Thread breakage	Incorrectly threaded	Thread correctly (see pages 7-10)
	Thread has caught	Check whether thread catches at the reel stand, etc.
	Thread tension too tight	Regulate tension, (pages 15, 16)
	Needle not fully inserted	Insert needle correctly (page 22)
	Incorrect needle used	Use needle system 130/705 H
Skipped stitches	Needle bent or point damaged	Insert new needle
	Needle not fully inserted	Insert needle correctly (page 22)
	Incorrect needle used	Use needle system 130/705 H
	Incorrectly threaded	Thread correctly (pages 7-10).
Incorrect stitch formation	Incorrect setting of thread tensions.	Set thread tensions correctly (pages 15, 16)
Puckered seams	Thread tension too tight	Reduce thread tension (especially for light materials) (pages 15, 16).
	Incorrect setting of differential feed.	Re-adjust differential feed.
	Thread has caught due to incorrect threading	Thread correctly (pages 7-10).

Accessories

1 Screwdriver (big)
2 Screwdriver (small)
3 Lint brush
4 Tweezers
5 Upper knife
6 Thread unreeling disc
7 Needles
8 Sewing machine oil
9 Rolled hem sewing foot
0 Thread spool net
1 Needle change tool

Thread spool net

Very useful for synthetic threads which tend to become loose, unravel and slip down (Fig. A)

Thread unreeling disc

The thread unreeling disc shown as item 6 of the accessories is used for smaller thread spools.

Remove thread spool centering piece 36 from the thread reel pin.

Put the thread spool on the thread reel pin and place the thread unreeling disc on top of it, with rounded-off section C facing down, as shown in Fig. B.

Specifications:

Maximum sewing speed	1,300 stitches/min
Seam width	3-5 mm
Stitch length	1-5 mm
Sewing foot	Hinged
Lubrication	Manual
Sewing foot height	5 mm
Needle system	130/705 H (no. 75 - no. 90)
Number of threads	4
Dimensions	315 x 280 x 330 mm
Weight	approx 80 kg

Contents of cardboard box

1 machine with motor
1 foot control
1 instruction manual/guarantee certificate
1 lint box
1 thread spool stand
4 thread spool stand bars
1 thread guide
1 machine cover