The Challenge 1640 is a versatile mechanical sewing machine with 40 built-in stitches, one-step buttonhole, automatic needle threader, drop-in bobbin system, adjustable stitch length and width, free arm capability, built-in LED light, and variable speed control. Powered by 120V AC, 60Hz. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.
Key components: Mechanical sewing head, built-in stitch patterns, automatic needle threader, drop-in bobbin system, free arm, accessory storage.
| Feature | Description |
|---|---|
| Built-in stitches | 40 different stitch patterns including utility, decorative, and stretch |
| One-step buttonhole | Automatic buttonhole creation with precise sizing |
| Automatic needle threader | Easy threading with built-in threading mechanism |
| Drop-in bobbin system | Top-loading bobbin with clear cover for easy monitoring |
| Free arm capability | Convertible for sewing sleeves and cuffs |
| Variable speed control | Adjustable sewing speed with foot pedal |
| Built-in LED light | Bright illumination of sewing area |
| Stitch length/width adjustment | Customizable stitch dimensions |
| Reverse stitching | Reinforce seams with reverse stitch button |
| Accessory storage | Built-in compartment for feet and accessories |
Unpack and inspect contents. Place on stable sewing table.
WARNING! Machine contains sharp needles; handle with care. Ensure stable placement to prevent tipping.
Prepare machine for first use with proper threading and bobbin winding.
CAUTION! Keep fingers away from needle area during operation. Always turn off when threading.
Access stitch selection via dial controls. Front Panel: Stitch selector dial, stitch length dial, stitch width dial, reverse stitch button.
Additional Controls: Power switch, bobbin winder, thread tension dial, presser foot lever, hand wheel.
Stitch Selection: Turn dial to choose from 40 built-in patterns. Stitch Length: Adjust from 0-4mm for different fabric types. Stitch Width: Adjust from 0-5mm for zigzag and decorative stitches. Tension Control: Dial adjustment for perfect stitch formation. Reverse Stitch: Hold button for backstitching at beginning and end of seams.
Various presser feet and accessories for different sewing techniques.
Tip: Always use correct presser foot for specific techniques (zipper foot for zippers, buttonhole foot for buttonholes).
Fundamental sewing techniques and machine functions.
WARNING! Never pull fabric while sewing; let feed dogs move fabric. Keep fingers clear of moving needle.
Automatic needle threader: Push lever to thread needle easily. Drop-in bobbin: Easy loading with clear view window. Built-in LED: Consistent lighting for precise sewing.
Unplug before cleaning. Remove lint and dust from bobbin area and feed dogs regularly.
CAUTION! Use only sewing machine oil for lubrication. Do not use household oils. Keep machine covered when not in use.
UL Listed: Certified for electrical safety in household use. Copyright © 2025 Challenge Sewing Machines; trademarks of Challenge Manufacturing Co. For support, visit www.challengesewing.com or contact 1-800-555-SEWING.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| Thread breaking | Incorrect threading/tension | Rethread machine; adjust tension; check for burrs on needle. |
| Needle breaking | Wrong needle/bent needle | Replace needle; ensure correct insertion; check for hitting pins. |
| Uneven stitches | Tension issues | Adjust upper and bobbin tension; rethread completely. |
| Machine not feeding | Feed dogs lowered | Raise feed dogs; clean feed dog area of lint. |
| Bobbin thread bunching | Incorrect bobbin threading | Remove and rethread bobbin; ensure correct direction. |
Maintenance: Oil moving parts every 6 months with sewing machine oil only.
Service: 1-800-555-SEWING; www.challengesewing.com