Metal Grinder 50mm (Tsunami Glass)

Metal Grinder 50mm by Tsunami Glass

The Metal Grinder 50mm from Tsunami Glass is a 4-part aluminium herb grinder that turns whole dried herbs into an even, fluffy consistency in seconds. At 50mm across, it sits comfortably in one hand — substantial enough for a proper grip, compact enough to toss in a bag. The built-in pollen catcher on the bottom layer means you're not wasting a single crystal of your herb. It's the kind of grinder you buy once and forget about, because it just works.

Why a 50mm Metal Grinder Beats the Alternatives

We've sold grinders of every size and material over the years — acrylic, wood, ceramic, metal in every diameter from 40mm to 63mm. Here's what we've learned: 50mm is the sweet spot for most people. A 40mm grinder works, but you're loading it twice as often. A 63mm beast is brilliant at home but absurd in your jacket pocket. The 50mm Tsunami Glass grinder handles a solid pinch of herb per load without feeling bulky.

The teeth on this one are worth mentioning. They're diamond-shaped with sharp edges, arranged in a pattern that pulls herb down into the grinding chamber rather than just pushing it around. You get an even, fluffy result rather than chunks on one side and powder on the other. That consistency matters — whether you're rolling, packing a bowl, or loading a vaporiser, even particle size means even burning or heating.

The honest limitation? At 50mm, this is a mid-size grinder. If you regularly grind large amounts in one go — say, for batch-rolling sessions — you'll be reloading a few times. For that, you'd want a 63mm grinder. But for daily, single-session use, 50mm is the best size for portability without compromise. We'd pick this over most 40mm grinders every time — the extra 10mm of diameter makes a noticeable difference in how much herb you can process per twist.

How the 4-Part Design Works for You

A 4-part grinder gives you three separate chambers stacked on top of each other, plus the lid. The top two pieces — lid and grinding plate — do the actual work. Your herb falls through holes into the second chamber once it's ground fine enough. Below that, a fine mesh screen separates the herb catch from the bottom pollen chamber. Over a few sessions, trichome dust (the good stuff) sifts through the screen and collects in that bottom compartment. After a week or two of regular use, you'll have a nice little pile of concentrated pollen. Nothing goes to waste.

The magnetic lid is a small detail that makes a big difference. It keeps the grinder shut when it's bouncing around in a bag or pocket. No surprise herb spills. We've seen too many people learn that lesson the hard way with non-magnetic grinders — one fumble and your freshly ground herb is decorating the floor.

How to Use the Tsunami Glass Metal Grinder 50mm

1. Unscrew the lid from the grinding chamber. Break your dried herb into smaller pieces by hand — roughly pea-sized — and place them between the teeth. Don't overfill; leave room for the teeth to do their job. About 1-2 grams of loose herb per load works well.
2. Replace the lid. The magnet will snap it into place. Hold the bottom half of the grinder in one hand and twist the lid back and forth with the other. 8-10 rotations is usually enough for a fine, even grind.
3. Unscrew the grinding chamber from the herb catch below it. Your freshly ground herb is sitting in the middle section, ready to use.
4. Check the bottom pollen chamber every week or so. Unscrew it from the herb catch to find your collected trichome dust. A small scraper or guitar pick works well to gather it.
5. Clean the grinder every few weeks. Disassemble all 4 parts, brush out residue with a stiff brush or old toothbrush, and wipe the threads with isopropyl alcohol on a cotton bud. This keeps the twist smooth and prevents the parts from sticking together.

From Our Counter: What We've Noticed

The weight of this grinder is the first thing you notice when you pick it up. It's got a solid, satisfying heft — not heavy enough to be annoying, but enough that it feels like a proper tool rather than a toy. The anodised finish on the metal is smooth under your fingers, and the threading between sections is clean. No cross-threading on the first twist, which is something cheaper grinders get wrong constantly.

One thing to watch out for: the pollen screen can get clogged over time if you're grinding particularly sticky herbs. When that happens, your pollen stops sifting through and the middle chamber fills up faster. A quick brush with a stiff-bristled brush — or even a few minutes in the freezer to make the residue brittle — sorts it right out. This isn't a flaw specific to Tsunami Glass; it happens with every screen grinder. Just part of the maintenance.

Compared to acrylic grinders at a similar price point, the difference is night and day. Acrylic teeth dull quickly, the plastic flexes under pressure, and they tend to crack if you drop them. Metal grinders like this one keep their edge for years. The 50mm Tsunami Glass is the best metal grinder for everyday use if you want something reliable without spending a fortune.

Frequently Asked Questions

Last updated: April 2026