Alrighty, today to my delight, we have a nice and easy build in this cute little box, courtesy
of my mate Kodazzle, courtesy of his mate Goddream.
And this is the Tentaku mechanical calculator from A&N Laboratory in Japan.
So we get all our little hardware pieces which includes stabilisers, feet, standoffs, and
screws.
And here’s the actual thing.
And you can pretty much see how it all goes together with 3 acrylic pieces and the actual
unit.
The reason why I was so delighted with building this, besides the whole cool factor, was that
there’s absolutely minimal soldering work needed.
Everything is soldered on, besides the keyswitches.
Normally for these sorts of things, you’d expect to have to solder on most of the parts,
but we’ll get back to that.
Here’s the acrylic pieces, with the base, plate, and cover for all the components at
the top.
Acrylic is especially useful for DIY kits like this.
Nice and cheap, and gets the job done.
Having a closer look at the PCB and the components.
There’s only the standard numpad layout, so completely fixed, and it supports MX style
keyswitches, which you will have to supply yourself, as the kit doesn’t come with any.
Then everything else is up top.
Here are the LED display thingos, in which there are 2 side by side.
Quite big things actually, nice and thick.
I did a quick Google on these and didn’t find them, because I’m hoping they cost
a little bit to justify the price.
And on the right-hand side we have our on and off switch, very basic.
And on top is our slot for a AAA battery, so yes, it is a completely independent unit.
I never really show this stuff, so I might as well now.
Bandaid mod just because.
Not necessary at all, just gives that extra little bit of softness for the bottom out
on the stabilised keys.
And these are just fabric bandaids cut up.
The included stabs are standard Cherry clip ins.
It’s actually been quite a while since I’ve used clips in, rather than screw ins.
And actually clipping the stabs in fact, as most modern ones come pre-clipped.
And as always, lube your stabs.
I went pretty heavy here with some dielectric grease.
I was given some Gateron Browns, so a light tactile keyswitch.
And I decided to lube them with Christo MCG 111.
And this is the only part where you actually have to solder, so you will need an iron to
do this.
But it’s super beginner friendly for soldering.
2 pins for each keyswitch, and that’s it.
I did make this more complicated for myself though, like the absolute novice that I am.
These switches were kind of loose in the 1.5mm acrylic plate, so everytime I put a new keyswitch
in, the plate would go down.
So then I decided to put the whole thing together, to hold the plate up, and you’ll see why
that makes completely 0 sense.
And clearly I didn’t read the instructions, in which they do have a PDF of, and even a
build guide video.
And this worked really well for putting in the keyswitches.
But yeh.
Now you can’t solder.
And because of that, I decided that actually we needed some clicky switches in here.
It’s a novelty product, and you’ll be showing people, so you definitely need a few
clickies, and I went with Kailh Box Whites.
In the guide they do say to put the switches into the plate first, which makes complete
sense.
Being quite flexible though, the switches do easily pop out.
Honestly, if you haven’t soldered before, give it a go.
It’s easy as, and is just a really useful skill and tool to have in life.
This however is as easy and as basic as it gets, making a really cool DIY gift for beginners.
I ended up going with GMK Minimal, thanks again Jono.
Although I was given SA Miami nights, but I felt something shorter was better suited,
and because of the translucent black acrylic on top, I think the black and white theme
is super classy.
And yet another mistake from not reading the instructions.
There’s a proper direction the black acrylic piece needs to go, as it was hitting the keycaps.
Before I turn it on.
The plate and base were clear, and I wasn’t liking the look, especially with this black
and white aesthetic I have going on.
I took a real gamble here and decided to colour in the sides with a Sharpie, including
the PCB.
So so cool.
The good news is, is that after soldering, literally all you need to do is to switch
it on, and it works.
No flashing or configuring or anything.
It just works straight away.
And well, that’s because it really is JUST a calculator.
It’s not programmable, you can’t plug it into a computer, so it’s not a numpad,
sooo yeh very much more of a novelty thing, again a perfect gift for a tinkerer in which
this actually was.
But I love it.
And I think the black acrylic sides do look especially aesthetic.
With GMK Minimal on top, it looks super classy, but mixed with the super DIY look with the
acrylic and open sides, so we can see all the components, it makes for an unexpected
match in my opinion.
Although the gamble didn’t fully pay off, as the Sharpie does come off a little bit
on the fingers.
The numbers are nice and bright.
Really bright actually which looks perfect under the translucent black acrylic.
So actually using it.
Num lock is the clear button, enter is equals, and then everything else is as labelled.
It can handle up to just 6 digits.
So we can only input that many, and it can only output that many.
So if we do say 500k plus 600k to make 7 digits, it comes up with error.
Very very basic, but I’m totally cool with that.
I do have a Ducky Pocket which is like the legit version.
Works independently with a battery, but can also plug into a computer and be used as a
numpad.
And of course comes in a complete package with switches, keycaps, RGB backlighting,
etc etc.
But in a weird sort of way, if I came across these in a store, I’d get the Tentaku just
because it’s cooler and you get to build it.
I have a mix of lubed Gat Browns and Kailh Box Whites.
I lubed both the stabs and the Browns pretty heavily, so they ended up being pretty quiet,
which is the opposite to the Box Whites.
And even more so, because check out this mad flex.
Nice soft bottom out, no need for any other dampening.
The kicker though is that it’s listed at 5500 Yen online, which is like 50USD.
This was picked up in Japan though, so I don’t know how much it was there.
But a Ducky Pocket is like 70USD.
So it is pretty pricey, especially since it is very basic being just a calculator, and
adding in switches and keycaps will increase that.
Ignore the fact that I used GMK keycaps on here, which makes this quite the unit.
But it is what it is.
I really loved how it turned out.
It really is very aesthetically pleasing to me with the raw but classy look.
It’s extremely beginner friendly for soldering work.
You just chuck in the switches, solder, turn it on, and it’s all good.
So disregarding the price, this is legitimately one of my favourites builds I’ve done, ever.
So if you’re looking for something fun, possibly for someone else, especially for
mech people, I think this is awesome.