The Singer Spool Pin Spring (part # 172512) is a specialized metal spring designed for the pop-up spool pin assembly on vintage Singer Slant-Needle sewing machines. This spring acts as a holder and tension provider for the spool pin (#172509), ensuring the pin stays in place and operates smoothly during sewing. The spring is critical for the "pop-up" functionality of the spool pins found under the top lid of high-end vintage Singer models.

Specifications:

• Part Number: 172512
• Type: Replacement 
• Material: Metal spring
• Application: Pop-up spool pin assembly
• Function: Holds and provides tension for spool pin #172509
• Quantity: Sold individually

Machine Compatibility:

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

Key Function and Design:

This spring is critical for the pop-up mechanism that allows spool pins to retract under the top lid of high-end vintage Singer models. It serves as the standard replacement for worn-out, rusted, or missing springs in the spool pin assembly. The spring provides the necessary tension to keep the spool pin (#172509) securely in place while allowing smooth operation during thread delivery.

Related Parts:

This spring works with Spool Pin #172509 for complete pop-up spool pin assembly.

Installation Note:

Simple installation - the spring is designed to fit precisely over the spool pin holder. Replace a worn-out, rusted, or missing spring to restore proper pop-up spool pin function and ensure secure thread spool retention during sewing.