I’m not sure if crazing is a British term… or if it’s just something my family made up at some point.

Either way, it’s a topic that comes up in almost every Bootcamp -usually because delegates have seen it many times but never knew what it was called… or why it happens.

So let’s clear it up.

Crazing = micro‑cracks in the surface of acrylic caused by stress, chemicals, or heat. They don’t always break the material, but they do weaken it and make it look cloudy, cracked, or frosted.

If you’ve ever made a beautiful acrylic plaque, placed it on the dispatch table for QC, and had it bounced because it’s suddenly covered in tiny cracks…

Or worse – installed it, only for the client to call the next day saying it’s “cracked”… That’s crazing. And once it starts, you can’t fix it.

It weakens the panel, makes illumination patchy, looks unsightly, and leads to premature failure.

Why crazing happens (the real causes inside sign shops)

1. Solvent / Alcohol exposure

Acrylic hates solvents, alcohols and harsh cleaners and extruded acrylic is especially vulnerable. Even a quick wipe with a rag that has alcohol on it can cause crazing if the sheet is under stress or has micro‑scratches.

Cast acrylic is more stable BUT if the edges have been laser‑cut or flame‑polished those edges will crack instantly when exposed to solvents.

2. Stress from fabrication

▪️ Over‑tightened fixings

▪️ Poorly designed folds

▪️ Too much heat during bending

Cast acrylic reduces the risk, but technique still matters.

3. UV + age

Older acrylic (especially extruded) becomes brittle and far more prone to crazing.

4. Wrong adhesive

Using the wrong glue, or too much solvent cement, can attack the surface and trigger crazing.

So how do we prevent crazing (the part your team really needs)

▪️ Use cast acrylic for anything fabricated or lasered

▪️ Advise clients to clean signs with mild soapy water, not chemicals

▪️ Don’t overtighten fixings

▪️ Use adhesives designed specifically for acrylic

▪️ Let laser‑cut parts “rest” before assembly

▪️ Avoid exposing stressed acrylic to solvents

We touch on these fundamentals in The First Drill and Signage Bootcamp, because crazing is one of those issues that quietly costs sign shops time, money, and reputation.

If crazing (or any other fabrication mystery) is driving your team crazy, reach out.

We can map out practical, confidence‑building training that helps your staff understand why things go wrong and not just how to fix them after the fact.

Drop me an email – michelle@makeih.com