Managing Pallet Temperature and Avoiding Over-Flashing

Two of the most overlooked variables in screen printing are pallet temperature and flash control. Both have a direct impact on print quality, inter-coat adhesion, and overall consistency. This seemingly simple tip sets apart the elite printers from the machine operators that just press and guess. Let’s break down why they matter and how to manage them.

Over-Flashing: Stabilize, Don’t Cure

A flash unit’s job is simple: gel the ink, not cure it. The goal is to make your underbase stable enough to accept the next layer of ink without sticking to and building up on the screen.

If you over-flash and fully cure the underbase, you create a hard film that the top coat of ink can’t properly bond to. This leads to poor inter-coat adhesion, which often shows up as ink flaking off in the wash or other wash-related issues.

Think of it like painting a car: the base coat is porous, designed to “grab” the top coat. If the base coat is sealed off (cured), the top coat has nothing to bite into. In screen printing, the same principle applies—your underbase should remain soft enough for the top layer to fuse into it.

Pallet Temperature

As a print run goes on, pallets heat up. Hot pallets, in turn, heat the bottoms of your screens. Once the screen surface gets hotter than the garment surface, ink begins to migrate toward the screen instead of staying on the shirt. The result? Ink build-up and print defects.

Here’s a way to visualize it: when sweating copper pipes together, you heat the female side of the joint so the solder flows toward it. Ink behaves similarly—it’s drawn toward heat. Now, you might think a hot pallet would draw the ink downward, and it would, except the garment itself acts as an insulating barrier. Meanwhile, every squeegee stroke transfers pallet heat into the screen, making the screen surface hotter than the shirt surface. That’s why build-up occurs.

How to Measure Pallet Heat

Managing pallet temp starts with measuring it correctly. Use an infrared laser thermometer right after a pallet comes out from under the flash. Keep in mind, you’re only measuring reflected surface heat, not the core pallet temperature—so the numbers are guidelines, not absolutes.

Here’s what to aim for:

• Standard cure inks (320°F cure): keep pallet surface readings between 140–150°F

• Low cure inks (270°F cure): keep readings closer to 125–130°F

Anything higher, and you risk screen build-up, adhesion issues, and unstable printing conditions.

How to Control Pallet Temperature

If your pallets are creeping too hot, try these adjustments:

• Lower flash energy (if your flash unit allows)

• Shorten flash time to avoid over-gelling

• Slow down the press. Even a slight adjustment to squeegee speed buys the pallets recovery time

• Adjust dwell time if needed. Remember: your ink needs 60 seconds in the dryer to anneal fully. You should only print as fast as your dryer can process prints.

Pro Tip: If you’re stopping frequently to wipe screens because of ink build-up, you’re already losing more time than you would by running a touch slower.

Final Thoughts

Flash control and pallet management are easy to overlook, but they’re critical for consistent results. Keep your underbase soft enough for proper inter-coat adhesion, and manage pallet heat so the ink stays where it belongs—on the garment, not the screen.