Casio SUF-100 – Restoration

Introduction

Every once in a while, you stumble on a Casio that feels like a time capsule from the early 90s. That’s exactly what happened when I found a Casio SUF-100 Surfing Timer from 1991 in a second-hand shop. This watch is pure retro surfing culture. It has a bold wave-style dial, a rotating bezel for timing, and a plastic case that originally came in bright pink. Back then it was Casio’s way of mixing sports function with fun design.

When I picked it up, it was far from ready to hit the waves. The strap was missing, the battery was dead, the glass was scratched, and the once-vibrant pink had faded to a dull orange. Still, something about this oddball model made me want to save it. Watches like these are not the icons everyone talks about, but they show Casio’s creative side. For me, that makes them worth restoring. 🏄‍♂️⌚

What was the initial condition of the watch?

The SUF-100 was not in terrible shape when I found it. It was missing a strap. The battery was dead. The acrylic glass had scratches. And the original bright pink resin had faded into an orange tone from years of sun and age.

One accident made it worse. I wore the watch on a hike before the restoration. While spraying Mugga mosquito repellent on my arm, some of it hit the case. The strong chemicals damaged the printed text on the bezel. The letters started to peel, so I had no choice but to polish them off later.

Overall, the watch was still solid. It just needed some care to bring back the colors, clear up the glass, and get it running again.

How did the restoration process go?

Step 1: Cleaning the case

I started with a deep clean. Warm water, mild soap, and a soft brush were enough to remove years of dirt. After drying, I used an oxidant polish to bring back the faded resin. The orange case slowly revealed its original bright pink color, which is the signature look of this model.

Step 2: Polishing the glass

The acrylic glass had many scratches. I worked step by step with sandpaper: 800 → 1200 → 2000 → 2500 grit. After that I applied Polywatch to finish the polish. The result was a smooth, clear surface with almost no marks left.

Step 3: Battery replacement

I opened the back, checked the gasket, and fitted a fresh battery. The watch powered up immediately. No issues with the module, which was a relief.

Step 4: Strap replacement

To make the SUF-100 wearable again, I sourced a new strap. It is not the original, but the fit and style match the watch. Fresh spring bars secured it in place.

Step 5: Fixing the damaged text

The Mugga repellent had eaten away at the printed bezel text. I polished the surface carefully until all loose fragments were gone. It left the bezel clean and uniform, without half-damaged letters.

Step by step, the SUF-100 started looking like a watch again. The pink case shined, the glass was clear, and the functions came back to life. 🛠️⌚

What challenges came up during the restoration?

• Faded color. The resin had turned from pink to orange after years in the sun. I was not sure if it could be saved. Careful polishing with oxidant brought the bright pink back.
• Scratched acrylic glass. The crystal looked rough at first. It needed patient sanding through several grits before Polywatch could make it clear.
• Damaged bezel text. The Mugga mosquito repellent accident removed part of the original lettering. Instead of leaving half-flaked marks, I polished the bezel clean.
• Missing strap. Finding a good replacement was not easy. I finally sourced a strap that matched the watch and fitted it with fresh spring bars.

Each of these problems looked small on its own. Together, they made the SUF-100 a real project. Solving them step by step was the only way to bring this surf timer back to life. 👍

What is the final result?

After all the work, the Casio SUF-100 Surfing Timer came back strong. The case shines again in its original pink tone. The acrylic glass is clear. The watch runs with a new battery, and the new strap makes it wearable. On the wrist, it has the same loud retro-surf energy it had in 1991. 🌊⌚

But one detail could not be saved. The original printed text on the bezel was destroyed by the mosquito repellent. I had to polish it off completely. The watch looks clean now, but without that lettering it is not the same. The bold text was a big part of the originality of this model.

Even with that loss, the SUF-100 is functional and vibrant again. It went from a faded relic to a colorful, working Casio that can still turn heads.