Can a rubber mold that has torn in production be repaired?

Although a repair may not be permanent, you can repair either a silicone or urethane rubber mold so that you can at least get a few more castings. You can then use that a casting to make a new mold.

Repairing a silicone mold – use Sil-Poxy silicone rubber adhesive. Important; all surfaces to be bonded must be clean. Use acetone or other solvent to clean the area to be bonded before applying adhesive.

Repairing a urethane mold – use Ure-Bond urethane rubber adhesive. Important; all surfaces to be bonded must be clean. Use acetone or other solvent to clean the area to be bonded before applying adhesive.

Disclaimer
This FAQ article is offered as a guideline and offers possible solutions to problems encountered during mold making and casting. No warranty is implied and it is up to the end user to determine suitability for any specific application. Always refer to the provided Technical Bulletins (TB) & Safety Data Sheets (SDS) before using any material. A small scale test is suggested to determine suitability of any recommendation before trying on a larger scale for any application.