Singer CG-590 C Service Manual

The Singer CG-590 C is a heavy-duty commercial-grade sewing machine designed for professional use, featuring a high-speed straight stitch, automatic lubrication system, and robust construction for continuous operation. This manual provides comprehensive information for service technicians, including safety procedures, technical specifications, disassembly/assembly instructions, troubleshooting, maintenance schedules, and parts diagrams. Below are key sections for service and repair.

1. Safety Precautions 2. Technical Specifications 3. Machine Overview & Components 4. Disassembly Procedures 5. Assembly Procedures 6. Lubrication System 7. Timing Adjustment 8. Needle & Hook Alignment 9. Tension Adjustment 10. Troubleshooting Guide 11. Parts List & Diagrams

Safety Precautions

Before servicing, disconnect power and follow safety protocols.

Hazard	Precaution
Electrical Shock	Unplug machine before opening covers or servicing electrical components.
Moving Parts	Ensure machine is completely stopped. Do not activate motor during service.
Sharp Components	Wear cut-resistant gloves when handling needles, hooks, and knives.
Hot Surfaces	Allow machine to cool after extended use before servicing motor or lubrication points.
Chemical Exposure	Use gloves when handling lubricants and cleaning solvents; ensure ventilation.

WARNING! Only qualified technicians should perform service. Incorrect repair can cause injury or machine damage.

Technical Specifications

Model: Singer CG-590 C
Stitch Type: Single-needle, lockstitch (straight stitch)
Maximum Speed: Up to 5500 stitches per minute (SPM)
Stitch Length: Adjustable 0-5 mm
Needle System: DBx1, size #11-21 (70-110)
Presser Foot Lift: Manual, 10 mm maximum
Motor: Clutch motor, 550W, 220V/110V (depending on region)
Lubrication: Automatic oil circulation system with visible oil tank
Machine Weight: Approximately 35 kg (77 lbs)
Dimensions (LxWxH): 450mm x 200mm x 350mm

Machine Overview & Components

Key components: Head, arm, bed, motor, handwheel, stitch length regulator, tension assembly, take-up lever, needle bar, hook assembly, bobbin case, feed dog, presser foot.

Head: Houses main shaft, needle bar mechanism, and take-up lever.
Arm: Contains upper tension assembly and thread guides.
Bed: Holds hook assembly, bobbin case, and feed dog mechanism.
Motor & Belt: Located under table; drives main shaft via V-belt.
Control Pedal: Regulates speed; connects to motor controller.

Note: Refer to Parts Diagram (Section 11) for component identification.

Disassembly Procedures

Follow sequence to avoid damage. Document screw locations.

Unplug machine. Remove needle, presser foot, and throat plate.
Remove top cover screws; lift off cover to access upper mechanism.
Remove side covers to access hook area and lower shaft.
To remove needle bar: Loosen set screw, slide bar out from top.
To remove hook assembly: Remove race cover, loosen hook holder screw, extract hook.
For main shaft removal: Remove handwheel, loosen pulley set screw, slide shaft out toward arm.

CAUTION! Label all parts and screws. Do not force components.

Assembly Procedures

Reverse disassembly order. Ensure all parts are clean and lubricated.

Install main shaft: Insert through arm, align timing marks, secure pulley.
Install hook assembly: Set hook in place, align with driver, tighten screw.
Install needle bar: Insert into bushing, align at top position, tighten set screw.
Reinstall covers and throat plate.
Check timing and needle-hook clearance (see Section 8).

Tip: Use manufacturer-recommended torque for screws. Test run without thread first.

Lubrication System

Automatic oil pump circulates oil to bearings, shafts, and hook race.

Oil Type: Use only Singer recommended sewing machine oil (light grade).
Oil Tank: Located at rear of head. Fill to MAX line; do not overfill.
Check Flow: Run machine at low speed; verify oil reaches sight glasses.
Manual Points: Also oil needle bar bushing, presser foot bar, and tension discs periodically.
Oil Change: Drain and refill every 500 operating hours or annually.

WARNING! Incorrect oil can damage seals and bearings. Never run machine without oil.

Timing Adjustment

Correct timing ensures proper stitch formation.

Set needle at highest position (top dead center).
Remove throat plate and bobbin case.
Rotate handwheel until needle begins descending.
When needle is 2.2 mm above needle plate, hook point should be at center of needle, approximately 1-1.5 mm above needle eye.
Adjust by loosening hook driver set screw and rotating hook slightly.
Tighten screw and recheck.

Note: Use timing gauge if available. Incorrect timing causes skipped stitches.

Needle & Hook Alignment

Clearance between needle and hook is critical.

Needle to Hook Clearance: 0.05-0.1 mm when hook passes needle.
Needle Alignment: Needle must be perfectly straight in bar; replace if bent.
Hook Check: Inspect hook point for wear or burrs; polish or replace if damaged.
Bobbin Case Alignment: Ensure bobbin case sits flush; adjust spring tension if thread loops underneath.

Tool: Feeler gauge recommended for clearance measurement.

Tension Adjustment

Balanced tension produces even stitches.

Upper Tension: Turn dial clockwise to increase, counterclockwise to decrease. Standard setting: 4-5.
Bobbin Tension: Adjust small screw on bobbin case spring. Turn slightly (1/8 turn increments).
Test: Sew on two layers of test fabric; stitches should lock in middle, no loops on top or bottom.
Checkpoints: Ensure tension discs are clean and spring is not fatigued.

Tip: Always adjust with machine threaded and under normal operation conditions.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Skipped stitches	Incorrect timing, bent needle, worn hook	Check and adjust timing; replace needle; inspect hook.
Thread breaking	Burred needle eye, incorrect tension, rough thread path	Replace needle; adjust tension; polish thread guides.
Uneven feed	Worn feed dog, incorrect pressure, debris	Replace feed dog; adjust presser foot pressure; clean under plate.
Noisy operation	Low oil, worn bearings, loose parts	Check oil level; inspect bearings; tighten screws and covers.
Motor does not start	Pedal fault, broken belt, electrical issue	Test pedal continuity; check belt; verify power supply and fuse.
Oil leakage	Overfilled tank, worn seals	Drain to correct level; replace shaft seals if necessary.

Reset: For electronic errors, power cycle machine.

Parts List & Diagrams

Reference exploded-view diagrams for part numbers and assembly order.

Diagram A: Head Assembly (Needle bar, take-up lever, linkages)
Diagram B: Hook & Bobbin Assembly (Hook, race, bobbin case, shuttle)
Diagram C: Feed Mechanism (Feed dog, lift cam, adjusting eccentric)
Diagram D: Tension Assembly (Tension discs, spring, dial, regulator)
Diagram E: Motor & Drive (Motor, pulley, belt, pedal connector)

Ordering: Use exact Singer part numbers when ordering replacements. Contact authorized Singer parts distributor.

Service Support: For technical assistance, contact Singer Industrial at 1-800-4-SINGER or visit www.singerindustrial.com.