Avoid getting a headache by understanding the principles of Cap design.

Troubleshooting Cap Decorating

Caps serve the purpose of keeping heat from escaping from our heads, the sun out of our eyes and a bad hair day under wraps, all while delivering a personalized statement of loyalty, interests and endorsements to the world. A lot of good from a little wearable, but on the flip-side, they are also often many a decorator’s nemesis.

No matter what the method, the rounded design of a cap can cause an inevitable headache to those embellishing it.

While it may seem easier to disregard structured headwear altogether, a better understanding of what to expect in each discipline, and how to combat popular problems can help alleviate some of the head trauma.

Curved Heat Press

While one of the more verstile disciplines, heat transfers require cap-specific equipment like a curved heat press to keep deigns smooth. (Image courtesy Geo Knight and Co.)


Embroidery is the most traditional of decorating methods for caps. Popular retail styles such as six-panel caps and over-sized, off-center designs have become increasingly popular in the decorated and promotional markets. However, it is still one of the more problematic practices. A major cause of this is the movement involved with stitching. To stitch on a curved surface, the machine must turn and rotate the cap, which usually turns it more than desired, points out Andrea Bommarito, Prodigi, who also notes that hooping is another major factor.

A headwear hoop is a long flexible bracket with clips on the back rails which holds the cap in place… but only to an extent, Bommarito says. A cap frame, as opposed to a round T-shirt hoop which supplies full coverage of the garment, can grip only the bottom and part of the cap’s sides. This fact results in considerable slippage, image distortion, puckering and flagging.

One way to combat bad stitching is to begin at the digitizing level. Hirsch’s Ed Levy suggests digitizing from the center out, which pushes the material away from the curve of the cap and prevents excessive puckering. Levy also suggests using a light zig-zag stitch beneath the seam to help build and stabilize the construction, creating a smoother, more uniform area for stitching.

Varying the stitch direction and sequencing, adds Bommarito, will also help. She explains that a balanced stitch direction will accommodate push and pull while enhancing the design itself, and sequencing can fill the large areas, followed by the outline or details, to help eliminate shifting. She also mentions distortion as a key culprit in design—when digitizing a circle it can oftentimes end up looking oval. She suggests looking at the stitch angle and how that affects the material in the area. From there, adjust the design to where it may not look right on the screen but will result in a properly-formed design.

Flagging is another problem common to cap embroidery that causes bobbin threads to show through the front of the cap. The jostling of the sewing also results in broken needles and cap frames. Even though this is most commonly caused by stitching a cap that has too much curve for the machine, Levy advises that a tear-away backing can help by reducing the space between the needle and the cap plate. This same solution can be realized with a cap-specific needle plate, which features a raised center that closes the gap when the presser foot and needle stitch.

Finally, Bommarito notes that a combination of steam to make the cap more pliable, underlay and a semi-wide cap frame are all good aids to get around the troublesome center-seam.

Screen Printing

Many would assume that the age-old practice of screen printing would have perfected the process for caps by now. But the best solution that’s been presented thus far is to print the caps pre-fabrication. “The best quality screen prints are done on the cap prior to assembly,” notes Nazdar’s Dave Julo. This may be best, but not common practice.

In most cases, caps are pre-assembled, ready for decoration, in a variety of styles, notes Mark Vasilantone, Vastex. “If caps were more uniform, one universal system could accommodate all styles,” he says. Since this is not the case, a variety of different platens and techniques are necessary for the various seams, crown heights and fabrics.

Another wrench in the screen printing process is screen tension. Even working on cap-specific platens and screens, the curved nature of the screens do not allow uniform tension. Julo explains that less tension provides a lot more opportunity for distortion and movement. To counter, a printer’s best bet is a good hold-down, he remarks.

A cap’s bill also poses its own unique problems. When working around the bill, Vasilantone suggests using a screen that has one side made with a metal bar to assist in pulling it down to allow the user to print as close to the base as possible.

Other problematic construction features include raised seams. If the seam overlaps, it can be very difficult to get even coverage, Julo reports. Special platens with lowered centers that accommodate the excess fabric and help build up either side of the seam can be used in this case. Coupled with a thicker ink deposit, low off-contact and a limited color selection, print practitioners are able cover the raised profile, reducing cracking and gaps in the design.

Both Vasilantone and Julo agree that large or overly-complicated, multi-color designs are the easiest avoidable problems when screen printing caps. “Keep it simple. Small, forgiving and one-color is generally the best approach,” states Vasilantone.


The biggest obstacle when printing directly on caps with a digital direct-to-substrate/garment (D2) printer, says Mark Bagley, Digital Marketing Solutions, is getting the printable area of the cap at the proper distance from the bottom of the print heads. Too far of a gap, he explains, can cause blurry designs, while printing too close can result in unexpected head strikes that damage the print heads.

Printing on machines with industrial print heads is the best bet, he says, since these designs typically have a larger gap, making it easier to print on areas like seams and bills.

Like any other dark item being printed with a direct-to-substrate machine, the pre-treatment is a vital step to maintaining bright colors and washability. However, in the case of headwear, where moisture-management is a popular feature, another important additive is polyester pre-treat fluid to prevent inks from wicking. Bagley suggests utilizing a wide strip of painters tape to protect the areas that do not require pretreatment.

As with other decorating methods, a flat printing surface is a desirable surface. Bagley states that many manufacturers have cap platens which flatten and mount the cap to the machine. To make these platens work to full potential, the bill must be held at or below the height of the printable area, never above.

Beyond this, he notes to consider the cap selection—structured styles have additional backing behind the front panels that make it stiffer and thus harder to flatten and print. Bagley suggests opting instead for unstructured caps, job permitting.

Heat transfers

Heat transfers are arguably one of the easiest forms of cap decoration. The biggest factor here is the press itself. While a flat heat press may work on the bill of a cap, Geo Knight and Company’s Aaron Knight notes, “A cap press is a common necessity by the sheer nature of the curved surface not staying smooth and clean.”

Rounded cap heat presses feature interchangeable upper platens to accommodate various types of designs from low profile, full crown, oversized or low crown, for example says Stahls’ Cara Cherry.

The bottom platen plays a role as well. Knight reports that many will order the next size down to better fit the caps to the press, which creates a smoother design while accommodating a wide variety of styles.

While not nearly as problematic as embroidery or screen printing states Cherry, the dreaded center seam still plagues this versatile medium. Highly pronounced seams can make transfers look bumpy or cause the inks to adhere incorrectly. Knight’s advice: “Revolve artwork and the style of the heat transfer embellishment around the limitations of the cap.”

Regardless of the medium, the limitations of cap design are set by construction, tools and know-how. With a little troubleshooting and trial-and-error, caps can become part of your repertoire