Durston 1303 Gem Ring Stretcher - 148.349

Durston 1303 Gem Ring Stretcher - 148.349

The Durston 1303 Gem Ring Stretcher is purpose-built for enlarging stone-set rings without disturbing the setting. By selectively stretching the ring shank opposite the stone, this tool allows jewelers to size up rings that would otherwise be difficult or impossible to resize using traditional methods.

To use, select the roller that best matches the profile of the ring shank, place the shank on the center die, and roll back and forth across the bottom of the shank to gently and evenly stretch the metal. Once stretched, the ring can be rounded on a steel ring mandrel to restore its shape and finish the sizing process.

While not suitable for every stone-set ring, the Durston Gem Ring Stretcher accommodates the majority of shank profiles and thicknesses. The included 17-piece roller set provides the flexibility needed to work across a wide range of ring styles.

Features

• Selectively stretches the ring shank opposite the stone setting
• Allows sizing of most stone-set rings without removing the stone
• Choose from included rollers to match the ring shank profile
• Center die supports the shank during the stretching process
• Rolling action provides gentle, controlled metal stretching
• Finish resizing by rounding on a steel ring mandrel
• Includes a 17-piece roller set to accommodate most shank thicknesses

Specifications

What our Experts Think

• Precision Solution for Tight Ring Adjustments
  The Durston 1303 Gem Ring Stretcher (148.349) is designed to carefully enlarge stone-set rings without removing stones or stressing the setting, using controlled mechanical stretching.
• Stone-Safe Expansion Method
  Works by applying pressure to the ring shank opposite the setting, helping maintain prong security while gradually increasing ring size.
• Multi-Roller System for Versatility
  Includes a 17-piece roller set to accommodate different shank shapes and thicknesses, ensuring accurate contact and controlled deformation across a wide range of rings.
• Designed for Professional Bench Use
  Built with a heavy-duty cast iron body and bench-mount capability, providing stability and repeatable results in repair environments.
• Controlled, Low-Risk Adjustment Process
  Unlike aggressive stretching methods, this system gradually rolls and elongates the metal, reducing the risk of cracking, thinning, or loosening settings.
• Workshop Efficiency Tool
  Ideal for jewellers handling frequent ring resizing work, especially when speed and stone safety are both priorities.
• Durston Engineering Reliability
  Made to professional standards for long-term durability, smooth operation, and consistent sizing accuracy.

Q&A

Maintenance Tips

• Clean after use: Remove metal particles and polishing residue from mandrels and expanding components.
• Light lubrication: Apply a small amount of machine oil to moving parts and threaded sections for smooth expansion.
• Protect gemstone-safe operation: Ensure rings are properly aligned and stones are secure before stretching to avoid damage.
• Avoid over-expansion: Stretch gradually in small increments to prevent tool strain and ring distortion.
• Inspect mandrels regularly: Check for wear, scoring, or deformation that could affect accuracy.
• Keep mechanism aligned: Ensure smooth, centered operation to maintain even pressure distribution.
• Store in dry conditions: Wipe down with anti-rust protection and keep free from moisture and dust