Lid for Kinu m47 coffee grinder - Review and making of

Lid for Kinu m47 coffee grinder - Review and making of

It's quite a strange thing to make a review on your own products. I usually prefer to just enjoy them after creating, since the main reason I produce something - is to fix something in my life.

And while it’s true for the first lid / cover that I’ve created (which is just a 3d printed lid) - it took way more resources to produce a proper one. So I decided to also make your life better by making a long lasting, predictably reliable and from the material which will look good.


The beginning

The initial shape is intended to be ergonomic (so that it’s easy to take and most importantly take off the grinder). But it’ll look too weird on the grinder, so I switched to the “dome shaped” lid. Overall concept remained untouched - I wanted a lid, not an insert which is tricky to take out. My fingers are too big for such tasks.

lid cover for kinu m47 concept

I did a couple of them initially, but the fit wasn’t good. It’s hard to predict how it’ll fit, because precision is the key here. And after a couple of attempts, I’ve made an extraordinarily good one. Though, the look is still “3d”.


Production

While it was tempting to make it with my own hands, it’s better to rely on professionals. Luckily there is a company which has special equipment for doing just that. Though the process takes ages, I finally received the first sample and was completely satisfied with the result. 

Smooth, durable with the perfect outside texture. Sits extremely reliably on my Kinu m47 Phoenix. Even makes the grinding slightly quieter. Of course, some particles are able to fly out through the planned gap, but it was night and day compared to using it without the lid, when I always had particles near the coffee corner. And the main part - I don’t risk any of them flying into my face, that’s the main part.

Everything was great until I shipped it to my mate who owns the Kinu m47 Classic model. Which happens to have slightly different dimensions. “It falls away!” he said. At this moment I was shocked. I did everything so perfect and after all of that - it doesn't work. I couldn't accept this fact. 

After figuring out what’s the root of the problem, I tried to modify the lid to have a lower height. So that it’ll lock properly when attached. The height of the lid is the only thing that prevents it to be perfect. 

Taking off the material, which is polyurethane, was a very intense work. I didn’t expect it to be THAT durable. My sharpest scalpel couldn’t cut it like I wanted. After 15m of work I ended up with this: 


But with the rollerblading background, where the wheels are also made out of polyurethane, I remembered about the most exciting discipline - slides. When you stop by having friction between the wheels and asphalt. Which partially takes off the material from the wheel and in some cases - even makes it square. 

So I grabbed the file and finished the work and shipped the lid.


Kinu m47 Classic - Silicone Rubber lid

After that, similar work was done to ship the lid to the customer. So I decided to make a lid which is specifically designed for Kinu m47 Classic.

The first concept I wanted to try is the new locking mechanism - to lock it on the handle itself, not the knob. So that I’ll not end up with the countless amount of units until it fits perfectly. For that, I’ve ordered an SLS print. Which looks very nice, but it’s extremely dense and sounds terrible. And the mechanism doesn’t work as expected.


Then, I nailed the thinner version from TPU (also 3d print), which to this day is my favorite. Flexible enough to be pleasant, but not too flexible to hold the shape nicely.

I also wanted to make it from silicone rubber this time, to have zero smell (which polyurethane has. It’s not noticeable, unless you receive the batch of 30 units in a sealed bag. Or sniff the lid from a distance of a few centimeters). And higher flexibility. Because polyurethane, while being a great option, with which you can easily throw the grinder into a backpack without the case and it’ll not fall off - it requires a little bit more force to attach than I want. I usually press it down with two thumbs to lock completely. Or press with the palm.

This time I decided to not even check the first sample and received the whole batch.

Lid for Kinu m47 Classic - First impressions 

Right away I understood that it wasn’t the right choice to make it that thin. While it worked extremely well for 3d - here the material is way softer. And when trying to attach it for the first time - slight disappointment signals were running through my brain. It was skewed and didn’t sit properly on the handle. 


Even though this lid has a bigger gap on my grinder, which is Phoenix, I wanted to test it to be sure it is usable. And just with a couple of attempts felt the relief. I needed to get used to this feature - flexibility. The only thing that needs to be done here - to align it before pressing with the palm. Or with the thumbs. And the great thing - I can take it off with ease by just squeezing. No force required unlike Polyurethane for Phoenix. 

It became my favorite lid and I’m using it now despite the gap. The only thing it lacks - is the ability to stop the handle from rotating by touching the lid. But I adapted to that by tilting the grinder by 45 degrees. 

Yes, it collects the dust more easily, but it works seamlessly. Even with such a gap - the amount of coffee particles on the floor is still close to none after a week of use. And I can finally proceed to the next projects. Which I recently did - the coffee filter holder for big filters like Chemex. 

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