Glue sticks – 11 or 12 mm diameter?
We keep getting questions like: “Do 12 mm sticks also fit in an 11 mm glue gun?” or “Is there a difference between 11 and 12 mm glue sticks?”
The short answer: There are neither 11 nor 12 mm sticks!
As hot glue guns are originally from the USA, the measurements are not based on metric dimensions. The glue stick normally has a nominal diameter of ½ inch, which is approx. 12.7 mm.
Other common sizes are:
- Mini hot glue sticks in 5/16″ (referred to as 7 mm)
- Hot glue sticks in 1/2″ (referred to as 11 or 12 mm)
- Hot glue sticks in 5/8″ (referred to as 15 or also 18 mm)
In addition, there are also exotics such as 1″ diameter or ⅝“ with a corrugated surface.
Technical tolerances in glue stick diameter
Another factor is the manufacturing process of the glue sticks: These are filled into the mould while hot and then cool down before being cut to length (often to 20 or 30 cm). In doing so, they contract somewhat, which leads to slightly different diameters depending on the composition.
Hot glue guns move the stick gradually into the heating chamber by means of a mechanical transport system. A seal also prevents the hot glue from escaping to the rear. Both systems have a technical tolerance regarding the exact diameter of the stick.
So, whether a glue stick manufacturer decides to specify their glues as 11 mm or 12 mm sticks does not change the usability.