Singer Heavy Duty 6700C User Manual

The Singer Heavy Duty 6700C is a high-performance sewing machine designed for demanding projects. It features a powerful motor, 70 built-in stitches, an automatic needle threader, a top drop-in bobbin, a one-step buttonhole, adjustable presser foot pressure, and a heavy-duty metal frame. Below are key sections for safety, features, setup, operation, maintenance, and troubleshooting.

1. Features at a Glance 2. Installation & Setup 3. First-Time Use 4. Specifications 5. Controls and Settings 6. Stitch Selection & Functions 8. Maintenance & Cleaning 9. Regulatory Information 10. Troubleshooting

Features at a Glance

Key components: Heavy-duty metal frame, LED work light, automatic needle threader, top drop-in bobbin system, built-in stitch patterns, and accessory storage.

FeatureDescription
Built-in Stitches70 stitches including basic, decorative, stretch, and buttonholes
Automatic Needle ThreaderEasily threads the needle with a lever
Top Drop-in BobbinClear view bobbin system for easy monitoring
One-Step ButtonholeAutomatically creates a buttonhole of precise size
Powerful MotorHeavy-duty motor for sewing through multiple layers
Adjustable Presser Foot PressureFor handling different fabric thicknesses
Stitch Length/Width DialAdjustable for custom stitch settings
Reverse Stitch LeverFor reinforcing seams
Free ArmFor sewing cuffs and tubular items
Accessory StorageBuilt-in compartment for feet, needles, and tools

Installation & Setup

Unpack and inspect contents. Place on a stable, flat surface.

  1. Assemble the Machine: Attach the accessory tray (if detachable) and the free arm cover.
  2. Power Connection: Plug the foot controller into the machine, then plug the power cord into a standard 120V AC outlet.
  3. Install the Needle: Loosen the needle clamp screw, insert the needle with the flat side facing back, and tighten the screw.
  4. Wind the Bobbin: Place thread on the spool pin, guide it through the bobbin winder tension disc, and wind onto the bobbin.
  5. Insert the Bobbin: Place the wound bobbin into the bobbin case with thread pulling counterclockwise. Pull thread into the slot.
  6. Thread the Upper Thread: Follow the numbered threading path on the machine and use the automatic needle threader.

WARNING! Keep fingers away from the needle area during operation. Always turn the handwheel towards you.

First-Time Use

Power on the machine; the LED light will illuminate.

  1. Test Stitch: Place a scrap fabric under the presser foot. Lower the presser foot lever and gently press the foot controller to sew a few stitches.
  2. Adjust Tension: For balanced stitches, the upper and bobbin threads should lock in the middle of the fabric. Adjust the tension dial if necessary.
  3. Select a Stitch: Turn the stitch selection dial to choose your desired pattern.
  4. Practice Basic Functions: Try the reverse stitch lever and the stitch length/width adjustments.

CAUTION! Always unplug the machine before changing needles, cleaning, or performing any maintenance.

Specifications

Controls and Settings

Access functions via dials and levers on the front and side of the machine.

Main Controls: Power Switch/ Light, Stitch Selection Dial, Stitch Length Dial (0-4 mm), Stitch Width Dial (0-6 mm), Reverse Stitch Lever, Bobbin Winder Spindle/Stop.

Basic Settings:
Thread Tension: Adjust dial for balanced stitches (usually 4-5 for medium weight fabrics).
Presser Foot Pressure: Adjust lever for thick or thin fabrics.
Needle Position: Use handwheel to raise/lower needle. The machine stops with needle up by default.

Stitch Selection & Functions

Supports a wide variety of sewing techniques for garments, crafts, and home décor.

  1. Selecting a Stitch: Turn the stitch selection dial to the icon or number of your chosen stitch.
  2. Straight Stitch: Use for basic seaming. Set stitch length as needed.
  3. Zigzag Stitch: For finishing edges, appliqué, or sewing stretch fabrics. Adjust width and length.
  4. Decorative Stitches: Select from built-in patterns. Practice on scrap fabric first.
  5. Buttonhole: Attach the buttonhole foot. Select the one-step buttonhole symbol. Place fabric under foot and start sewing; the machine will complete all four sides automatically.
  6. Blind Hem & Stretch Stitches: Use the appropriate stitch and foot for invisible hems or sewing knits.

Tip: Always match the needle type and thread to your fabric for best results.

Maintenance & Cleaning

Regular maintenance ensures optimal performance and longevity.

  1. Daily Cleaning: Unplug machine. Use the small brush provided to remove lint from the feed dogs, bobbin area, and needle plate.
  2. Oiling: Refer to the manual for specific oiling points. Use only high-quality sewing machine oil. Apply 1-2 drops as instructed.
  3. Needle Replacement: Replace the needle after every project or 8 hours of sewing. A dull needle can cause skipped stitches or fabric damage.
  4. Storage: Cover the machine when not in use to prevent dust accumulation. Store in a dry place.

WARNING! Never use compressed air to clean the machine as it can force lint deeper into the mechanism.

Regulatory Information

FCC Compliance: This device complies with Part 15 of the FCC Rules. Operation is subject to the condition that it does not cause harmful interference. Copyright © Singer Manufacturing Company. All trademarks are the property of their respective owners. For support, visit www.singer.com or contact Singer Customer Service at 1-800-4-SINGER.

Troubleshooting

SymptomPossible CauseCorrective Action
Machine does not runNot plugged in / Power switch offCheck power cord connection and ensure power switch is ON.
Thread bunching underneath (bird nesting)Incorrect threading / Bobbin inserted wrongRe-thread the upper thread and bobbin, ensuring correct direction and path.
Skipped stitchesDull/bent needle / Wrong needle for fabricReplace needle with a new, correct type (e.g., ballpoint for knits).
Needle breaksWrong needle size / Pulling fabric / Bent needleUse correct needle size, do not pull fabric, let feed dogs move it. Insert needle properly.
Uneven or loose stitchesIncorrect tensionRe-thread completely. Adjust tension dial gradually. Check for lint in tension discs.
Fabric not feedingPresser foot pressure too low / Feed dogs loweredIncrease presser foot pressure. Check that feed dogs are in the raised position.
Unusual noiseLint or thread jam / Lack of oilUnplug, clean bobbin area thoroughly. Oil machine if needed.

Reset: Unplug machine for 60 seconds to reset electronic components if experiencing erratic behavior.

Service: For persistent issues, contact authorized Singer service center. 1-800-4-SINGER; www.singer.com

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