Soldomat Solder Rings
Right-Tool had solid illustrations and was selling these gizmos for quite some time.
Enter Soldomat Rapid Solder Rings. A simple solder product that takes most of the error out of the job. You still must clean and prepare the joint, but the skill required in using just the right amount of solder at just the right moment to ensure proper solder flow, is unnecessary. The Soldomat solder ring provides just the right amount of solder and is applied cold into the fitting before coupling with the pipe. Apply the flame as usual and wait for the solder to appear at the edge of the fitting indicating a complete and solid joint. The solder flows from the inside to the edge and all around the joint at once. The conventional technique requires that the solder spread from one side around the joint to complete the seal, sometimes making it difficult to be sure the flow is complete. With the Soldomat Rapid Solder Rings the solder is visible all around the joint and since it came from the inside the seal is for sure complete. The product is available in three sizes, 1/2", 3/4", and 1" and sell 100 for $20.
These are pre-formed little rings of solder that slip into the fitting -- not bad -- can save a lot of time. But I cannot find them on Right Tool nor anywhere on the web. When the company comes back into business -- perhaps restrained by code approvals or capital -- please let me know.
Found them here:
Pace Machinery Group Inc.

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