Top Six Mistakes in Heat-Applied Graphics and How to Correct Them

Josh Ellsworth

Josh is the VP of sales, dealer channel for Stahls'. He deals in the sales and implementation of heat-applied, apparel-decorating systems with a focus on customization. He holds skills in the production, sale, and marketing of customized apparel. He presents seminars at trade shows and contributes articles to trade publications, like Printwear magazine.

When expanding into a new technology, everyone is a novice. Although easy to pick up, this story is no different when getting into heat-applied graphics. Working in the field for more than 10 years, I can attest that the same questions and problems come up time and again. Every once in a while there will be something unique, something we’ve never heard of before—but for the most part, the same usual problems arise. Here is a review of those six most common mistakes in heat-applied graphics.

Mistake #1: Oops—it’s crooked!

This could be the most common mishap with heat applied graphics. Is there really any way to make sure things are all lined up? Not exactly, or at least not without the help of lasers and rulers. But there are simple measures to prevent a crooked design from happening.

Start by ensuring the shirt is loaded onto the heat press straight. One tactic is lining up the tag with the backbone of the heat press. Once the garment is loaded correctly, the job gets a little easier. 

Sometimes, loading exactly straight is impossible, so consider this technique: fold the shirt in half, sleeve to sleeve, and press a center line in the garment. This line provides a placement mark for centering designs or positioning them properly for a left or right chest print.

Alternatively, some tools exist to help with this. These see-through plastic alignment grids make sure the shirt is on right. Or, for maximum production efficiency, consider a more elaborate system such as those that project a laser line onto the garment. 

Even with the tools available for the job, most keep it simple and do it by eye or with the help of a homemade template or simple ruler. Placing transfers 2" down from the collar or three fingers down (depending on the width of your fingers) is another good reference that’s always handy. Whatever way you choose, learn from the crooked transfer mistake and come up with a plan to keep things straight.

Mistake #2: They’re all backward! 

With heat applied film, sublimation, inkjet transfers for light colors or even with plastisol transfers, it’s necessary to mirror the image before cutting or printing. One of the most costly mistakes is running an entire order through the print process without mirroring the designs… only to realize it at the heat press before pressing the first one. 

Mistake #3: Uh oh, where did my design go?

This one plagues even the best. After going through a long run of orders on the heat press do you realize, oh yes, that transfer was placed upside-down. This can get messy.

Make a complete garment from start to finish, including pressing it, before printing and cutting the entire job. This will ensure the steps to print it properly were taken and it’s likely the rest will be right. Believe it or not, some industry software programs have prompts before you send the job to cut/print asking if you’d like to mirror the image. This helps, especially for those of us who make this a chronic problem.

Transfers applied upside-down get all over the heater. Clean it off with a non-abrasive cleaner and rag. Wipe the press while hot or warm and be sure not burn your hand. This is why some transfer manufacturers always recommend using a cover sheet on top of the design. This practice can prevent ever making this mistake, or at least make it less time consuming. Everybody does it once... if you haven’t, you will!

Mistake #4: Uh oh, where did my design go (the sequel)?

This time it’s not on the heater. It was pressed properly and all of the settings on the application sheet we followed. Still, the design is nowhere to be found on the garment. What gives? 

If decorating dark colored garments, be sure to use an opaque transfer technology. Printing on clear/transparent paper and pressing onto darks doesn’t work. Transfer paper manufacturers make solutions specifically for dark colors, so it’s important to know what color the transfer will be transferred to in order to select the right solution. 

Mistake #5: The heat press just melted the bag, scorched the jersey or discolored the T-shirt!

Different fabrics have different thresholds and melting points. Likewise, there are specific adhesives used for low-temperature applications. If using 375º for everything on the heat press, you’ve probably melted a few items. Take care when selecting a heat transfer for the specific type of fabric. Polypropylene/non-woven bags are the toughest, but there are compatible heat transfers that apply at a very low temperature in less time.

Also, this problem shouldn’t be confused with the discoloration of red or burgundy T-shirts when pressed. Often, you’ll see a big press marking; this almost always disappears within 15–20 minutes.

Mistake #6: I can’t believe it’s peeling off! 

This can be the scariest scenario when dealing with any form of decorating—when the garment is in the customer’s hands and then the decoration fails. It’s very important to implement some rules for heat pressing to prevent this.

  1. Always preheat the garment. Preheating helps release moisture and wrinkles that can affect adhesion. Preheat by locking the press down for a few seconds (possibly several times) on each shirt, until you can no longer see moisture releasing.
  2. Ensure adequate pressure. Remove any barriers to an adequate pressure by building the press area up with pads and pillows. If seams, buttons or collars are on the pressing area, they are absorbing pressure that is intended to be distributed to your graphic. Compensate by increasing pressure or removing the barriers.
  3. Temperature and time specifications need to be followed. Higher temperature isn’t always better. Likewise, more time isn’t always better. Transfer adhesives call out specific settings; use them to ensure long-lasting results.
  4. Check the “it sticks to” recommendations. Many transfer adhesives are great for cotton and polyester fabrics while others are intended to stick to nylon. Some work on mesh, others don’t. Choose a transfer that will stick to the intended fabric.
  5. Include care instructions. Not all heat transfers are created equal. Some will last through industrial wash cycles for workwear, while others, such as foils, must be line dried. Others call out specific instructions such as “do not dry on high heat.” Establish the types of transfers that will be utilized for decorating and then make it a point to come up with care instructions to be included with each order. Having these instructions can save a lot of headaches when everything else is done properly.

Now, there are plenty more mistakes that will happen along the way and, trust me, they have been made before. These mistakes turn into lessons; some even into new processes. Whether you’re a novice or an expert, don’t be embarrassed when you make a mistake. Learn from it and move on.