Manual for Singer Sewing Machine Dec 1948

The Singer Sewing Machine from December 1948 is a classic mechanical sewing machine featuring a cast-iron body, manual treadle operation, straight stitch capability, adjustable stitch length, built-in bobbin winder, tension control, and various presser feet attachments. This comprehensive manual covers operation, maintenance, threading, troubleshooting, and care instructions for this vintage model.

1. Features at a Glance 2. Machine Setup 3. First-Time Operation 4. Specifications 5. Controls and Adjustments 6. Threading Instructions 7. Stitch Settings 8. Maintenance & Oil Points 9. Care & Cleaning 10. Warranty Information 11. Troubleshooting

Features at a Glance

Key components: Cast-iron body, Treadle mechanism, Bobbin winder, Tension dial, Stitch length regulator, Presser foot, Needle clamp, Hand wheel.

Feature	Description
Treadle mechanism	Foot-powered operation for hands-free sewing
Bobbin winder	Built-in bobbin winding mechanism
Tension dial	Adjustable thread tension control
Stitch length regulator	Control for stitch spacing adjustment
Presser foot	Standard presser foot with lifting lever
Needle clamp	Secure needle holding mechanism
Hand wheel	Manual control for precise stitching
Thread guides	Multiple guides for proper threading path
Bobbin case	Front-loading bobbin system
Throat plate	Removable plate with stitch guidelines

Machine Setup

Unpack and inspect all components. Place on stable table or sewing cabinet.

Assemble treadle: Attach treadle mechanism to cabinet base following numbered diagrams.
Install belt: Connect drive belt between hand wheel and treadle wheel.
Level machine: Adjust leveling screws on cabinet for stable operation.
Oil points: Apply sewing machine oil to all designated points before first use.

WARNING! Machine is heavy; use assistance when lifting. Ensure all connections are secure before operation.

First-Time Operation

Prepare machine for initial sewing session.

Thread machine: Follow numbered threading guide from spool to needle.
Wind bobbin: Use built-in bobbin winder with empty bobbin.
Insert bobbin: Place wound bobbin in bobbin case following directional arrow.
Test stitches: Use scrap fabric to adjust tension and stitch length.
Practice treadling: Develop smooth rhythm with foot pedal.

CAUTION! Keep fingers away from moving needle. Always lower presser foot before sewing.

Specifications

Machine Type: Treadle-operated straight stitch
Stitch Type: Straight stitch only
Stitch Length: Adjustable 0-4mm
Bobbin Type: Class 66 metal bobbins
Needle System: 15x1 household needles
Tension Control: Dial adjustment 0-9
Presser Feet: Standard, zipper, buttonhole attachments available
Weight: 28 lbs (machine head only)
Materials: Cotton, linen, wool, light synthetics
Manufacture Date: December 1948

Controls and Adjustments

Primary controls: Stitch length regulator, Tension dial, Presser foot lifter, Hand wheel, Reverse stitch lever.

Stitch Length: Turn regulator clockwise for longer stitches, counterclockwise for shorter.

Tension: Higher numbers for tighter tension (heavier fabrics), lower for lighter tension.

Presser Foot Pressure: Fixed pressure suitable for most fabrics.

Needle Position: Center needle position standard.

Threading Instructions

Proper threading is essential for smooth operation.

Raise presser foot and needle to highest position.
Place thread spool on spindle.
Follow numbered guides: Through first thread guide, around tension discs, through take-up lever, down to needle.
Thread needle from front to back.
Pull up bobbin thread by turning hand wheel toward you.

Tip: Always thread with presser foot raised to open tension discs.

Stitch Settings

Straight stitch settings for various fabrics.

Light fabrics: Stitch length 1.5-2mm, tension 3-4
Medium fabrics: Stitch length 2.5-3mm, tension 4-5
Heavy fabrics: Stitch length 3-4mm, tension 6-7
Basting: Stitch length 4mm, tension 2
Gathering: Long stitch length with tight upper thread

WARNING! Test settings on fabric scrap before sewing project. Adjust tension gradually.

Maintenance & Oil Points

Regular maintenance ensures longevity and smooth operation.

Oil points: Bobbin case area, Take-up lever, Needle bar, Presser foot bar, Tension assembly, Hand wheel bearing.

Oil Schedule: Every 8 hours of use or monthly. Use only sewing machine oil.

Care & Cleaning

Unplug treadle belt before cleaning. Remove lint buildup with small brush.

Weekly: Brush out bobbin area and feed dogs. Wipe exterior with soft cloth.

Monthly: Remove throat plate for thorough cleaning. Oil all designated points.

CAUTION! Do not use compressed air; can force lint into mechanisms. Never use household oils.

Warranty Information

Original warranty: 25-year limited warranty on cast-iron parts. Serial number located on bed plate. For service, contact authorized Singer repair centers. This manual published December 1948 by The Singer Manufacturing Company.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Thread breaking	Incorrect threading/tension	Re-thread completely; reduce tension; check for burrs on needle.
Uneven stitches	Tension imbalance	Adjust upper and bobbin tension; ensure proper threading.
Machine jams	Lint buildup/thread tangle	Clean bobbin area; remove tangled thread; oil moving parts.
Needle breaks	Bent needle/wrong size	Replace needle; ensure proper insertion; use correct needle size.
Fabric not feeding	Presser foot pressure/dirty feed dogs	Clean feed dogs; check presser foot is lowered; replace feed dogs if worn.

Service: Contact authorized Singer service center for major repairs.

Parts: Genuine Singer parts recommended for optimal performance.