What is the Buckram of a Baseball Cap?

This is one of the more niche questions that our clients ask us about baseball caps.

So, what is the buckram of a baseball cap? Buckram is the fabric lining the inside of the front two panels of a baseball cap. It is made of stiff material (traditionally cotton), and gives the cap its shape. Most baseball caps have a buckram, though not all: baseball caps with this inner lining are called “structured caps”, and caps without this lining are called “unstructured caps”. With an unstructured cap, the cap gains its shape only when worn, as the wearer’s forehead supports the “structure” of the front of the cap. Let’s look into how it is made, and the functions it performs.

How Buckrams Are Traditionally Made (And Types)

Traditionally, buckram is made from cotton which has been soaked in a starch paste (to give it strength), before being allowed to dry. This buckram is typically sold to milliners (hatmakers) in sheets or rolls. Buckram comes in three standard weight classes:

·       Baby buckram [Light] – normally used in children’s and dolls’ hats

·       Single-ply buckram [Medium] – used to make baseball caps

·       Double-ply buckram [Heavy] – commonly used in costume headwear for theatre

For baseball caps, we are interested in single-ply buckram (with a weight of around 200 gsm), though strictly speaking even medium weighted buckram comes in different weights/thicknesses.

How The Buckram Is Applied To The Baseball Cap

After being cut to the correct shape, the buckram fabric is placed behind the front panels of the cap and lightly sewn into place along the outer edges. From there the buckram is fused in place behind the front panels by placing the fabrics into a mould and heat pressing the fabric layers together.

Before the buckram is sewn behind the front panels, the two front panels are themselves sewn together, then any embroidery and printing are applied beforehand. This is because, if we were to apply the buckram first and then embroider artwork onto the front of the cap, we would have two bad results:

1.       The embroidery machine would perform to a lower quality standard, as the machine would have to embroider through both the fabric of the front panels AND the (thick!) buckram.

2.       The back of the embroidery will show through the buckram, creating an unprofessional-looking finish.

So, the buckram actually performs two roles. The first is the give structure to the baseball cap. The second is to hide the back of the embroidery.

This is why at HYPERSUPPLY, when we make caps, we always manufacture from scratch, first embroidering artwork onto the front panels, then applying the buckram after the embroidery stage. With other companies who claim to offer “customised” services, they are often just buying pre-made blank caps and embroidering onto them. The quality difference for the embroidered artwork on the front is huge, and increasingly savvy consumers can see the difference between truly custom-made caps (ours) vs “customised” caps (others) simply by looking at the underside of the hat and checking the buckram.

Quality is also the reason that the front two panels are sewn together before any artwork is embroidered onto the front of the cap: If the front panels were sewn together after the front artwork is completed, the top-stitching would sit on top of the artwork, ruining it.

This same logic extends to why, after embroidery artwork on the front panels, the buckram is sewn behind these panels along the outer edges of the whole shape: If the buckram were also sewn into place down the middle seam between the two front panels, any embroidery or printing on the front of the cap would again be ruined.

This also highlights a process which is purely for display purposes: If a cap has a buckram, then seam tape going down the middle of the buckram (see when looking at the inside of a finished hat) serves no real purpose (other than “symmetry”), as there is no exposed seam that needs to be sealed; the buckram is already covering the seam between the front two panels.

Modern Buckrums

Nowadays, the buckram can be made of either cotton or polyester (or a blend of both), is stiffened with either starch or a chemical additive, and is available in numerous colours beyond the standard white. The latter allows you to match the buckram with the colour scheme of the rest of the cap.

There is also a newer type of buckram available, called adhesive buckram. As the name suggests, this type of buckram glues itself to the front panels. It’s not simply a matter of putting this material behind the front panels, however. The material glues itself to the front panels after the application of heat and pressure from a thermal pressing machine. So, in the section above where we describe how the buckram is applied to the cap, we are using adhesive buckram in this case - and in most modern-day cases too. Here, one side of the buckram has heat-activated adhesive on one side, and this is the side which faces the back of the front panels before the application of heat.  

Really, buckram should be called as interfacing. In the rest of the apparel industry, interfacing is a term for fabric used on an unseen part of a garment, to make that area stiffer, and also to prevent that area from stretching out of shape. One example is the interfacing used to stiffen shirt collars, which increases the usable life of the shirt. Where the interfacing has heat activated adhesive, it is known as fusible interfacing. Without this adhesive, the interfacing would have to be sewn into place. However, remember that in the case for baseball caps, the buckram is typically lightly sewn into place (even though it is adhesive buckram), and will be fused to the front panels with the use of a thermal press.