The Mystery Of Gate Marks: Unlocking The Secrets Of Antique Cast Iron Pans

Gate marks are a line where a pan was broken from its mould. They are found on all cast iron pans and refer to the area where the piece separates from the pattern when it is made. In the 19th century, advancements in casting technology led to the technique of side gating, which moved the gate away from the bottom of the pan. Bottom gating was still used on large pieces like cauldrons, where side gating was impractical, and by smaller foundries. Bottom gating also continued to be used by individuals or small foundries making copies of other pans. While gate marks are not exclusive to antique cast iron pans, they can indicate that the pan is from the late 18th or 19th century.

Gate marks are a by-product of older iron casting methods

Prior to the adoption of side gating, the casting process was much simpler. Craftsmen would pack sand into a box, create a cavity in the desired shape, drill a hole, and pour molten iron into it. This traditional method, known as bottom gating, often left a noticeable mark on the bottom of the pan where the iron was poured into the mould.

While side gating offered improved aesthetics and convenience, it required more elaborate patterns with runners, multiple gates, and risers to ensure even filling of the mould. Companies like Wagner and Griswold, who entered the market during this transitional period, embraced side gating from the outset.

However, smaller foundries, particularly those producing large-format pieces like cauldrons, continued using bottom gating due to its practicality and simplicity. Additionally, individuals or small foundries creating copies of others' pieces also favoured the traditional method.

Today, gate marks are still present on modern pans, but they are typically found along the upper edge of the pan and are ground off as part of the finishing process, making them less noticeable compared to their vintage counterparts.

The presence of a bottom gate mark on a cast-iron pan often indicates production in the late 18th or 19th century. However, it's important to note that some foundries continued using bottom gating well into the 20th century, especially for larger pieces.

Bottom gating was replaced by side gating in the late 1800s

Gate marks, also known as casting marks, are lines on antique cast iron pans where the pan was broken from its mould. Advancements in casting technology in the mid-to-late 19th century led to the development of side gating, which replaced bottom gating. This new technique moved the gate away from the bottom of the pan, instead placing it on the side, where its remnant would no longer be physically obtrusive and any vestige of it could be rendered inconspicuous.

Side gating was an improvement on the previous method because it allowed the iron to fill the cavity more completely and evenly, from the bottom up, against gravity. However, it required a more elaborate process with runners and multiple gates and risers. Companies like Wagner and Griswold, who began hollow ware manufacturing around this time, used side gating from the outset.

Bottom gating continued to be used by smaller foundries without the capability to adopt the new technique, but they quickly fell by the wayside. Bottom gating also persisted for large pieces like cauldrons, where side gating was impractical, and for copies of other pieces made by individuals or small foundries.

While the shift from bottom to side gating happened in the late 1800s, some foundries continued to use bottom gating well into the 20th century.

Bottom gating continued to be used for large pieces like cauldrons

Gate marks, or casting marks, are lines on cast iron cookware that indicate where the pan was broken from its mould. In the 19th century, cast iron was poured into a mould through a line on the bottom of the mould, which left a mark on the iron once it hardened. This method of pouring iron through the bottom of the mould is known as bottom gating.

In the mid-to-late 19th century, advancements in casting technology led to the development of side gating, where the gate was moved away from the bottom of the mould to its side. This innovation allowed for a more aesthetically pleasing final product, as the lip of the pan could be ground down and made to look like the rest of the pan. Side gating also resulted in a more uniform cast, as it allowed the iron to fill the mould evenly from the bottom up, against gravity.

Despite the emergence of side gating, bottom gating continued to be used for large pieces like cauldrons, where side gating was impractical or deemed unnecessary. Bottom gating was also used for tall castings, where metal was slowly poured into the mould from the bottom of the cavity. Additionally, bottom gating was advantageous over top gating, as it resulted in less chaos and sand erosion.

However, bottom gating had some drawbacks. For instance, there was a risk of the metal flow getting clogged due to solidification before the mould was full. Additionally, the temperature range generated by bottom gating was often difficult to reach the standard, leading to uneven solidification.

Bottom gating was also used by individuals or small foundries making copies

Gate marks, also known as casting marks, are a line where the pan was broken from the mould. They stopped making them this way in the 1890s, so gate marks are a sign of a vintage cast iron pan.

In the mid-to-late 19th century, advancements in casting technology brought about the technique of side gating. This moved the gate away from the bottom of the pan, meaning any vestige of it could be rendered inconspicuous. However, bottom gating continued to be used by smaller foundries without the capability to side gate, as well as by individuals or small foundries making copies of other manufacturers' pieces.

Bottom gating was also used for large pieces like cauldrons, where side gating was impractical or unnecessary. It was also used for large format pieces like sugar kettles long after the majority of cookware manufacture had moved to side gating.

While it's difficult to identify the makers of unmarked cast iron pans, there are some clues to look out for. For example, the shape of the handle's hole, the contours of the top and bottom of the pan, and any raised or incised numbers or general markings. The typeface used could be a giveaway, or at least point you in the right direction.

If your pan has a brand label, comparing its logo design and font to other pans of the same brand can help give you an idea of when it was made. For example, Lodge's iconic egg logo was created in 1973, so any pan with just the name "Lodge" carved into it is at least over 45 years old.

Gate marks are the area where the piece separates from the pattern

Gate marks are an integral part of the casting process, and they are found on antique cast iron pans as well as modern cast products. Gate marks are the area where the piece separates from the pattern, and they can vary in terms of style and location depending on the specific casting process.

In the past, the technique of bottom gating was commonly used, where the gate was located at the bottom of the mould. This method left a noticeable mark on the final product, and it was often necessary to drill a hole or slot to create a path for the molten iron to fill the mould. However, with advancements in technology, side gating became prevalent in the mid to late 19th century. This technique moved the gate to the side, making it less obtrusive and allowing for more elaborate patterns with runners and multiple gates.

Today, there are three common types of gate styles used in plastic injection moulding: tab gates, hot tip gates, and pin gates. Tab gates are the most widely used and offer flexibility in placement. They produce a tapered rectangle that can be easily trimmed, but they may leave a larger witness mark. Hot tip gates, on the other hand, use a heated nozzle to keep the plastic at an optimal temperature, resulting in a small, round bump that can be trimmed flush. Pin gates, also known as post or tunnel gates, are typically used for parts that cannot have gate vestiges on the parting line or cosmetic side. This type of gate injects resin through a cone-shaped hole and is sheared off during ejection, leaving a small post that can be manually removed.

Gate marks are an inevitable part of the casting process, and their placement and style are carefully considered to minimise their impact on the final product's appearance and functionality.

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