Compared to the tubes they are joining, how are solder fittings generally described?

Solder fittings are generally described as being slightly larger than the tubes they are joining. This design allows for an effective fit that accommodates the expansion of the solder when it is heated. When solder is melted, it flows into the joint between the fitting and the tube, creating a strong bond as it cools and solidifies. The slight size difference ensures that the fitting can easily slide over the end of the tube, allowing for proper alignment and a secure joint.

In plumbing, achieving a tight, leak-free seal is essential, and this method of sizing ensures that the solder fitting can fulfill that requirement while also enabling a straightforward installation process. Having fittings that are larger by just a small margin facilitates a snug connection when assembled, which is critical for the integrity of the plumbing system.