NEVER USED A CONVEYOR DRYER FOR SCREEN PRINTING? HERE'S A GUIDE TO HELP YOU FIRE IT UP
How good is your SPM (shirts per minute) right now? Can you crank out 20, 50, 100 shirts an hour? One way to increase your output while enhancing the end result is using a conveyor dryer to cure garments. Conveyor dryers are faster and more efficient at curing prints compared to flash dryer or heat presses. Keep reading to learn more about conveyor dryers and how you can get one up and running in your shop soon.
HOW CONVEYOR DRYERS WORK
A conveyor dryer is a device that uses heat to cure a print. A conveyor dryer has a belt that carries the garment into a tunnel where the heating element sits above, emanating the heat down onto the print and garment. Conveyor dryers are the most optimal machinery for curing prints because they cover the entire garment, providing an even, consistent cure. They’re also the best because they keep up with large volume runs, allowing multiple shirts to be cured at once.
Multiple types and iterations of conveyor dryers exist and each has its own advantages. If you’re new to screen printing, working out of a small space, or have a lean budget, a small-but-mighty conveyor like the RileyCure Table Top will suffice.
HOW TO USE A CONVEYOR DRYER
Conveyor dryers come with standard controls like on/off switches for the belt and heating element and belt speed control. Larger dryers have more features like temperature control. With these settings you can adjust the dryer to accommodate the needs of the print and garment.
FACTORS THAT CHANGE DRYER SETTINGS
One factor you have to consider when selecting the settings is the garment type. Take cotton shirts for example. Cotton absorbs moisture. When it goes through the dryer, the moisture evaporates and becomes steam. The steam cools down the dryer, which means it’ll take longer for the print to hit full cure. On the other end of the spectrum is polyester garments. Since there’s no cotton in it, there’s nothing to absorb moisture and therefore, the shirt heats up quickly.
Garment density and thickness also plays a factor. Sweatshirts or hoodies are airy, so while it may be half cotton, the fabric has low density and can heat up quickly. Also, hoodies are thick so they sit higher up on the belt compared to a t-shirt. Since they’re taller, they’re closer to the heating element, which also speeds up the curing process.
Aside from garment types, the ink and ink deposit affect the dryer settings as well. Let’s start with ink deposit. The thinner the ink deposit is, the quicker it’ll cure (so, faster belt speed). The thicker the ink deposit is, the longer it’ll take to cure (slow down the belt).
Ink type will inform you what temperature the dryer should be at. Refer to the label on the ink container to learn what temperature the ink needs to reach in order for it to cure. Most inks cure between 260°F-320°F.
HOW TO RUN A TEST
Before you go into production, test the dryer to ensure it’s working properly. Here’s how to run a heating test:
- Plug the control panel into the proper circuit.
- Turn the Main Power Switch to the ON position. The green indicator light will illuminate.
- Turn the Belt Speed to the suggested speed located in your dryer’s manual. This will change a little bit depending on the dryer.
- Flip the rocker switch for Belt Speed to the ON position to start the belt. Listen for any unusual noises. Check if the rubber edge guide is riding in the TruTrak™ roller drum grooves.
- Turn the Heat Control to 5. Flip the rocker switch for Heat Control to the ON position. Do not operate the heating element when the belt is not moving. Heat can damage the belt.
- Verify that the heating element is functioning. After about a minute of operation, briefly feel just inside both the entrance and exit ends of the chamber. The area should be warm. Keep your hand close to the belt to avoid injury. Some smoke/vapor and odor may be noticed during the initial start-up due to residual material from the manufacturing process burning off the elements.
- The working temperature will be reached after a ten-minute warm-up. You can run a test shirt through to make sure the dryer is working properly.
Proper conveyor speed can be determined by placing a small item, like a coin, on the conveyor belt and recording the time it takes to travel through the chamber. Start a stopwatch once the coin enters the entrance to the dryer chamber. Keep the stopwatch going until the leading edge of the coin exits the dryer. The coin should stay in the chamber for a minimum of 30 seconds (recommended 40-45 seconds).
Once the dryer has been tested and determined that it is running well, create a test print and run it through the dryer. Once it has cooled down, perform a stretch test to start gaining preemptive knowledge on whether or not the ink has cured properly. For a true cure test, run the print through the washer and see how the print holds.
Increased output, faster production, and consistent cures are a few of the benefits printers experience when using a conveyor dryer. It’s an investment that pays itself back in no time. Increase your SPM today.