Seamless vs. Pressed Jars
Seamless or pressed, The Jar Store's glass containers are all candle-ready and produced using machines to ensure consistent and reliable candle making results. The selection of one over the other is a matter of personal preference and business application.
Seamless jars are machine blown using mass production lines that mimic the hand blowing process — but without the need for glass blowers. Blowing pipes attached to machines are tipped with molten glass and automatically injected into revolving molds. Air is time-released using special calibrators that ensure a consistent jar shape, size, thickness and weight. On the same production line, the jars are released from the molds, precision cut, heat tempered and flame polished. The resulting jars are seamless glass.
Pressed jars are manufactured using mass production lines that use a combination of blowing tubes and pressing equipment. The machine's blowing pipes create a molten glass balloon that is not directly injected into a single revolving mold. Instead, symmetrical halves of specific cast iron molds are automatically clamped around the glass balloon and steam-pressed together. Once released from the press, the resulting jars have small seams on each side at the exact point where the two halves of the mold were joined together.
0 items
in 
