Stop Struggling with Telegraphing

You’ve laminated a beautiful decorative surface onto a panel only to step back and see faint ridges and dips. When the surface of your core isn’t perfectly flat or uniform, those highs, lows, and patterns can “print” up through the overlay. That show-through is called telegraphing—and (good news!) it’s preventable.

In the plywood and laminate world, telegraphing is the visible (and sometimes tactile) transfer of substrate irregularities - voids, patches, grain raise, sanding ridges, or glue lines - through the overlay (HPL, TFL, foil, veneer, paint, etc.). It can appear as faint lines, ripples, or localized highs/lows that you can feel.

Beyond the obvious appearance issues, telegraphing adds cost and time: re-sanding, filling, and re-pressing are all expensive. It can also create downstream problems—uneven surfaces that throw off hardware fit, and compromised sealing and edge quality.

Because of the problems associated with telegraphing, it’s important to follow best practices during and before manufacturing has begun. Here are some steps you can take to prevent telegraphing:

·         Start with a quality core

Choose cores less likely to print through: higher-grade plywood faces or MDF for ultra-flat work. You may still need to fill and sand localized defects, but you’ll do less prep when the core is more uniform to begin with.

·         Prep the Surface

Be sure you’ve started with a flat panel and fill/sand any defects prior to laminating.

·         Acclimate Panels to Temperature

Keep your panels moisture content in a stable range and condition them to the shop’s humidity before laminating. Extreme changes in humidity can raise grain and move the panel after it’s been pressed.

·         Get your Glue Right

Use the adhesive system specified for your overlay and press. Apply a uniform spread as uneven application can cause glue lines which telegraph as lines or ridges.

·         Use a crossband

Use a crossband between the core and the decorative face to create a smoother, more uniform surface. This is standard practice in plywood and HPL/TFL layups when finish quality is critical.

There are many solutions to telegraphing, and it definitely doesn’t have to be an ongoing problem. If you’re struggling with telegraphing, we’d love to offer support and resources. Reach out to our team of experts today for help in achieving a perfectly balanced panel.