Check Spring 43946=8511 for Singer 31, 331K Sewing Machine
✉️ REQUEST PRICE, AVAILABILITY & SHIPPING
This item requires confirmation before ordering.
Current pricing, availability, lead time, and machine compatibility
will be verified for your specific requirement.
Please send your machine model, required gauge or size, quantity, and clear photos of the machine nameplate or existing components when available.
Please send your machine model, required gauge or size, quantity, and clear photos of the machine nameplate or existing components when available.
🌎 International customers are welcome.
We serve customers worldwide. Depending on product availability, orders may be sourced or fulfilled through our USA, Singapore, or international supply network.
Please include your destination country and postal code so we can review the most suitable shipping option.
REQUEST A QUOTE
We serve customers worldwide. Depending on product availability, orders may be sourced or fulfilled through our USA, Singapore, or international supply network.
Please include your destination country and postal code so we can review the most suitable shipping option.
U.S. customers may also text the product link and photos to
+1 (770) 744-3831
Check Spring (Part #43946 / 8511) – For Singer 31 & 331K
Ensure perfect tension and precise loop formation with the Check Spring (Part #43946 / 8511). This critical tension component is engineered specifically for Singer 31 and 331K industrial machines. It acts as the buffer for the upper thread, taking up the slack during the needle's descent and ensuring the thread is controlled at the exact moment the hook catches the loop.
Key Performance Features
High-Resilience Spring Steel: Manufactured from premium-grade tempered steel, providing the perfect balance of flexibility and "snap-back" required for high-speed industrial sewing.
Consistent Tension Control: Regulates thread slack to prevent "bird-nesting" and looping on the underside of the fabric.
Precision Coil Geometry: Designed to fit perfectly into the tension assembly of the Singer 31/331K series, ensuring smooth operation without binding or sticking.
Fatigue Resistant: Built to withstand millions of cycles, maintaining its tension strength even under the constant stress of heavy-duty production.
Most in-stock orders are processed within 3 business days, Monday through Friday. Special-order and non-stock items may require additional handling time
We ship from our Georgia, USA warehouse. If an item is temporarily unavailable in the U.S., we source it through our global supplier network and will notify you of the estimated lead time.
Free shipping is available on U.S. orders over $99.
Once your order ships, you will receive a tracking number by email.
For urgent orders or shipping questions, please contact us before placing your order.
We stand behind the quality of the products we sell.
• Genuine OEM parts are covered by the manufacturer's warranty where applicable.
• Aftermarket and generic parts are covered against manufacturing defects.
• If you receive a damaged, defective, or incorrect item, please contact us promptly. Please see our Return & Refund Policy for eligibility, notification requirements, and applicable return terms.
• Warranty does not cover damage caused by improper installation, misuse, normal wear, Return & Refund Policy modifications.
If you have any questions, our support team is happy to help before or after your purchase.