Stainless steel is my favorite wristwatch case material. It is tough, practical, and easy to polish to a fine mirror finish or an elegant brushed finish. But if you wear the watch long enough, it gets greasy and grimy. Some guys have watches that look like they have a special crusty exoskeleton that’ll need to be chiseled off.

We don’t want to be that guy, so how should we clean a steel watch?

Our Test Subject

For example, here’s a stainless steel Seiko case. The top is brushed, but the sides are polished to a mirror finish.

If you inspected this side of the case under a 10x loupe and raking light, you’d conclude that it is nearly flawless: virtually no swirls, scuffs, or micro-scratches. In fact, it’s hard to photograph because it so shiny that it is “black polished.”

This case is fresh from the polishing lathe and has some polishing compound on it, so we need to clean that off. But instead of polishing compound, you can imagine the gross paste of old skin cells, hand soap, and sweat that a gentleman’s watch eventually accumulates.

A lot of people will clean a watch like this with a soft toothbrush and some gentle dish soap. For example, here’s an old, soft-bristle child’s toothbrush.

The “toothbrush method” is widespread on the watch forums. On the jewelry-making forums, though, people know better. Even an old, soft brush will scratch your hard steel case.

Behold the enemy and its scowling and sinister visage!

To demonstrate, I ran the case and toothbrush under cold water, put some dish soap on the brush, scrubbed normally for around 10 seconds, and then dried the case with a clean microfiber cloth.

The case seemed unaffected to the unaided eye in normal light. Notice the excellent mirror finish on the case side.

But we are obsessive here at Adjusting Vintage Watches, whether we’re adjusting to positions or polishing a case, so what does the case side look like when magnified?

Here’s the case photographed at a raking angle under the LED. The light micro-scratches are easy to see.

A toothbrush will scrape off the gunk but leave small scratches behind, and removing those scratches will take some equipment and skill.

What to Do Instead?

So how should we clean our steel watch cases and bracelets?

It’s best if you can take apart the case and remove the movement. A jewelry steamer will work wonders on steel cases and bracelets. If you don’t have one of those, a heated bath in an ultrasonic cleaner will give excellent results. You’ll find dozens of cleaning solutions that will work well. I get great results with Simple Green diluted 1:1 with distilled water, for what it’s worth.

If you don’t have a steamer or ultrasonic cleaner, you know what to ask Santa to bring you for Christmas. Until then, you can use ammonia-based cleaners, like the streak-free blue stuff used on windows. A napkin or clean microfiber cloth dipped in the blue stuff can be used to dig out and dissolve your watch case’s grime.