Kannastor make one thing properly: a grinder you can tinker with. Where most grinders give you a single fixed mesh and that’s your lot, the Kannastor GR8TR lets you swap the screen for a coarser or finer one and store the result in a jar that screws onto the bottom. That’s the whole pitch, and it’s a good one if you’re particular about your grind.
People in Australia went looking for them for a simple reason. Dry herb vaporizers care a lot about grind texture, more than a pipe or a joint does, and being able to dial that in without buying three different grinders is genuinely handy. Add the built-in storage and you’ve got a grinder that does a job a normal one can’t.
It’s a small range. One grinder and the two parts that make it interesting. Here’s the honest version of each.
GR8TR V2
The GR8TR (say it “grater”) is a four-piece aluminium grinder, and the V2 is the current sizing. Teeth up top do the grinding, the ground herb falls through a screen in the middle, and a kief catch sits at the bottom. So far, so normal. The trick is the screen.
Instead of one permanent mesh, the V2 takes an Easy Change Screen you can pop out and swap. Coarse for a chunkier grind, fine for the fluffy, even texture that convection vaporisers love. That flexibility is the reason to buy one. Most people leave the fine screen in and forget about it, but the option’s there when you want it.
The teeth are sharp and the action is smooth once it’s worn in. New ones can feel a touch stiff for the first week, which is normal for any tight-tolerance aluminium grinder. The aluminium is anodised, so it won’t react with your herb. It’s a chunky unit, more bench grinder than pocket grinder, so it lives at home rather than in a jacket.
It doesn’t run a temperature, so there’s no °C to quote here. The number that matters is your vaporizer’s, and a fine, even grind from this lets you sit lower, say 180-190°C, and still pull good vapour because the heat reaches more surface.
Easy Change Screen
This is the bit that makes a GR8TR a GR8TR. It’s a swappable mesh plate that drops into the grinding chamber, held in place when the pieces thread together. Different plates give different hole sizes, so one grinder covers coarse, medium and fine without you owning three.
Why bother? Grind texture changes everything in a vaporiser. Too coarse and the hot air rushes past without touching much, so you get thin, wasteful draws. Too fine and it packs down, airflow chokes, and you’re sucking hard for not much. The Easy Change Screen lets you match the texture to the device instead of fighting it.
One quirk worth knowing. The screens are device-specific by diameter, so a plate sized for the V2 won’t seat in an older body and the reverse is true too. Buy the right one for your model. They clean up with a soft brush, and if one ever clogs with resin past saving, you swap a cheap part rather than bin the whole grinder.
Jar Body
The Jar Body replaces the standard kief-catch base with a small screw-on glass jar. Grind straight into it, twist it off, and you’ve got your herb stored and ready, no tipping the grinder out into a separate container.
For anyone who grinds a session’s worth ahead of time, it’s a nice touch. Less mess, less wasted herb stuck to the sides, and the glass lets you see how much you’ve got left. The trade-off is you lose the dedicated kief screen on the bottom, so heavy kief collectors will miss that. Most people don’t, and the convenience wins.
It’s glass, so treat it like glass. Screw it on firmly but don’t crank it, and don’t drop it on the tiles. Beyond that there’s nothing to it.
Living with one
The good news is everything comes apart. The pieces unscrew fully, the screen lifts out, and the jar twists off, so cleaning is just a tear-down and a soak. Iso alcohol and a soft brush gets resin off the teeth and out of the screen. Let it dry properly before you put it back together or the threads grab.
A finer grind clogs the screen faster, so if you’re running the fine plate, give it a quick brush every week or two and a proper soak monthly. Keep on top of it and the grinding action stays smooth. Let resin build up and it’ll feel gritty and stiff, same as any grinder.
If you want fixed, do-everything-well grinders to compare against, have a look at our herb grinders range, or the grinder parts for replacement screens and bits. Worth a read too: Introducing A New Herb Grinder Kannastor Gr8tr V2 for the background, and All About Grinders if you’re weighing up what actually matters in a grinder.
Which setup suits you
Quick version. Want to dial in your grind for a vaporiser: the GR8TR V2 with the fine Easy Change Screen in. Want to grind ahead and store it tidy: add the Jar Body. Just want a solid grinder and no tinkering: a plain four-piece from Santa Cruz Shredder, Space Case or SLX will serve you better and save you the fiddling.