Singer 6235 Service Manual

The Singer 6235 is a versatile sewing machine designed for home use, featuring multiple stitch patterns, adjustable stitch length and width, built-in buttonholer, free arm capability, and easy threading system. This service manual provides detailed information for maintenance, troubleshooting, and repair procedures to ensure optimal performance and longevity of the machine. Below are key sections covering safety, features, maintenance, adjustments, and troubleshooting.

1. Features at a Glance 2. Safety Precautions 3. Maintenance Procedures 4. Specifications 5. Controls and Settings 6. Needle and Threading 7. Tension Adjustment 8. Motor and Drive System 9. Troubleshooting Common Issues 10. Exploded View and Parts List 11. Warranty and Service Information

Features at a Glance

Key components: Stitch selection dial, stitch length/width controls, free arm, built-in buttonholer, drop feed, bobbin winder, reverse stitch lever, presser foot pressure adjustment.

Feature	Description
Stitch Patterns	Multiple built-in stitches including straight, zigzag, decorative
Buttonholer	One-step automatic buttonhole function
Free Arm	Removable extension table for cylindrical sewing
Stitch Length/Width	Adjustable controls for customization
Drop Feed	Allows for free-motion sewing and darning
Bobbin System	Top-loading, jam-resistant bobbin
Presser Foot Pressure	Adjustable for different fabric thicknesses
Reverse Stitch	Lever for reinforcing stitches
Lighting	Built-in LED work light
Power	Foot pedal control with speed adjustment

Safety Precautions

Always follow safety guidelines when servicing the sewing machine.

Disconnect power: Unplug machine before any maintenance or repair.
Use proper tools: Employ correct screwdrivers and lubricants as specified.
Avoid pinch points: Keep fingers clear of moving parts during adjustment.
Secure machine: Place on stable surface before servicing.

WARNING! Electrical shock hazard: Always unplug from power source before opening covers or accessing internal components.

Maintenance Procedures

Regular maintenance ensures optimal performance and prevents issues.

Cleaning: Remove lint and dust from bobbin area, feed dogs, and tension discs after each project.
Oiling: Apply sewing machine oil to designated points every 8-10 hours of use (see diagram).
Needle replacement: Change needle after every 8 hours of sewing or when dull.
Belt inspection: Check drive belt for wear and proper tension quarterly.

CAUTION! Use only Singer-recommended oil. Over-oiling can attract lint and cause staining.

Specifications

Model: Singer 6235
Stitches: 23 built-in stitches
Stitch Length: 0-4mm adjustable
Stitch Width: 0-5mm adjustable
Buttonhole: One-step automatic
Speed: Up to 750 stitches per minute
Needle System: 130/705 H
Bobbin: Class 15 transparent
Power: 110V, 60Hz (US/Canada)
Weight: 12.5 lbs (5.7 kg)
Dimensions: 15.2" x 6.7" x 12"

Controls and Settings

Front Panel: Stitch selection dial, stitch length/width controls, reverse stitch lever, bobbin winder.

Adjustments: Presser foot pressure dial, thread tension dial, feed dog position lever.

Stitch Selection: Rotate dial to desired stitch pattern (numbered 1-23). Stitch Length: 0-4mm (0 for darning). Stitch Width: 0-5mm for zigzag and decorative stitches. Tension: Adjust upper thread tension dial (3-5 for normal fabrics). Bobbin Winding: Disengage clutch by pulling handwheel outward.

Needle and Threading

Proper needle installation and threading are critical for good stitch formation.

Needle installation: Loosen needle clamp screw, insert needle with flat side to back, tighten securely.
Upper threading: Follow numbered path on machine; ensure thread passes through tension discs.
Bobbin threading: Wind bobbin evenly; insert with thread running clockwise through tension spring.
Thread pickup: Hold needle thread, lower and raise needle to catch bobbin thread.

Tip: Always raise presser foot when threading to open tension discs.

Tension Adjustment

Correct tension produces balanced stitches with no loops on either side.

Upper tension: Adjust dial (higher number = tighter tension).
Bobbin tension: Small screw on bobbin case (turn clockwise to tighten).
Test: Sew on scrap fabric; adjust until stitches appear identical on both sides.
Fabric considerations: Light fabrics may require looser tension; heavy fabrics tighter.

WARNING! Make small adjustments (1/4 turn at a time). Extreme adjustments can cause thread breakage.

Motor and Drive System

The motor and drive mechanism require periodic inspection and adjustment.

Belt Tension: Should have 1/2" deflection when pressed midway between pulleys. Brush Inspection: Replace carbon brushes when worn to 1/4" length. Handwheel: Should turn freely without binding. Clutch: Engages/disengages bobbin winding mechanism smoothly.

Troubleshooting Common Issues

Symptom	Possible Cause	Corrective Action
Thread breaking	Incorrect threading/tension	Rethread completely; reduce tension; check for burrs on needle.
Needle breaking	Bent needle/wrong size	Replace needle; ensure correct size for fabric; check alignment.
Skipped stitches	Dull needle/wrong type	Replace needle; use ballpoint for knits, sharp for wovens.
Uneven feeding	Presser foot pressure	Adjust pressure dial; clean feed dogs; check foot alignment.
Machine jams	Lint buildup/thread tangle	Clean bobbin area; remove tangled thread; rethread.
No power	Power cord/foot pedal	Check connections; test outlet; inspect foot pedal switch.
Noisy operation	Lack of lubrication/lint	Clean and oil machine; check for loose parts.

Exploded View and Parts List

Refer to diagrams for component identification and part numbers.

Major Assemblies: Head, arm, bed, free arm, motor, handwheel, bobbin case, feed mechanism. Fasteners: Screws, nuts, washers (specify sizes). Electrical: Motor, light, foot pedal, power cord. Common Replacement Parts: Needles (134R), Bobbins (40111), Belts (453251), Brushes (457341), Bulbs (457601).

Note: Always use genuine Singer replacement parts for optimal performance.

Warranty and Service Information

Singer 6235 comes with a 25-year limited warranty on the head, 5 years on electrical components, and 1 year on labor. Warranty requires proof of purchase and registration. For service, contact authorized Singer service centers only.

Service Centers: Locate at www.singer.com/service

Technical Support: 1-800-4-SINGER (1-800-474-6437)

Parts Orders: www.singerparts.com or authorized dealers