These bobbin winder springs are designed for Singer 500 and 503 Rocketeer sewing machines. The bobbin winder mechanism uses two springs to control the winding process: the return spring brings the winder back to its rest position after winding, while the release spring disengages the winder when the bobbin is full. These springs are essential for proper bobbin winding operation.

Specifications:

• Return Spring Part Number: 172552
• Release Spring Part Number: 172555
• Type: Replacement (aftermarket)
• Function: Controls bobbin winder engagement and return mechanism

Available Options:

• Return & Release Springs Set - Both springs (Part # 172552 & 172555)
• Return Spring - Part # 172552 only
• Release Spring - Part # 172555 only

Machine Compatibility:

Fits Singer 500 Series (Rocketeer): 500, 500A, 503, 503A

Function & Benefits:

The bobbin winder springs work together to ensure smooth, automatic bobbin winding. The return spring (172552) pulls the winder mechanism back to its rest position after winding is complete, while the release spring (172555) automatically disengages the winder when the bobbin reaches full capacity, preventing overwinding and thread breakage. Replace worn, broken, or missing springs to restore proper bobbin winding function.

Installation Note:

Replace damaged, stretched, or missing bobbin winder springs to restore proper winding operation. Ensure springs are correctly installed in their designated positions for proper engagement and release function.