C64 Mini Keyboard Kits – Now awaiting stock

Hi All,

It’s been a rollercoaster few days with the Retro Receipies Youtube video.

I’ve now run out of some components for the C64 Mini keyboard kit. More have been ordered, I’m just waiting on a last few people to send over payment and i’ll pause things for a few weeks until parts arrive.

I’m hoping that the delay also will help some focus to drive the keycap development and a feature change to the PCB

I have to say Thankyou to Perrifractic for reaching out and increasing the profile of this little kit, and that the response has been unexpected. This is a little hobby that I have in my spare time between juggling the bill-paying day job and the wife and kids, it gives me the pocket money to buy more gizmos to help develop these gizmos.

I ordered most of the ‘long lead time’ parts last week, so i’d expect it to now be mid-late february before I can sell more full kits.

Hello!

Just a quick ‘Hi’ to anyone popping in from Retro Recipes!

And, if you’re just browsing here due to something else, go, have a look at Retro Recipes!

Whilst you’re there, go check out my “This Old Tony” style cameo in the video 🙂 ! yes, that’s official, it’s my HOLLYWOOD DEBUT!.

Oh, And it’s a little video about the C64 Mini keyboard kits, and a little reveal!

And, to get in touch, ping an email to KEYBOARDS AT Bleugh.biz

Cheers

Dean

3D printing – UV Curing Resins

Not sure where i’ll be going with this post, but here goes anyway

The CAD work progresses with the C64 mini keyboard keycaps and it’s getting close to the time where I need to be thinking about the end-game, the final product.

I can’t imagine that people will be happy with some watery grey colour, most would prefer at least some semblence to the original breadbin colours!

So, i’ve done some quite considerable googling on the subject

.Also, figured that ‘painted’ stuff used to commonly use the RAL standard to determine a standardised final colour, maybe there’s a RAL colour for commodore keycaps? (there’s one for the case!)

Turns out that finding 3D printer resin in the colour you want, isn’t easy

Also, turns out that creating your own 3D printer resin colour also, isn’t quite fully tried and tested yet

https://formlabs.com/uk/blog/medical-dyeing-coloring-sla/

a fantastic website –

https://www.3dprintedminiature.com/how-do-i-dye-resin-3d-prints/

and, many, many more websites were found, all with various anecodes, photos and information regarding colourant successes and failures

One colourant kit that kept cropping up – https://monocure3d.com.au/product-category/cmyk-pigment-set/?v=322b26af01d5 The Monocure CMYK kit.

So, it looks like if I want to create my own coloured resin, I’ll have to mix it myself.

So, where to start, and what ‘stuff’ to use to dye it?

Turns out that there’s a distinct terminology that may need to be used to figure out just what the process of colouring resin is.

https://letsresin.com/blogs/articles/epoxy-pigment-guide-what-is-a-pigment-in-resin-art

has an interesting summary.

However, for my purposes of colouring the resin..

If I use a Dye – the colours will likley be a little more ‘washed out’

so, i’ll need to use a Pigment – essentially an insoluble bunch of micro particles that sit in suspension in the resin and create a solid, opaque colour! – AKA Dark brown.

So, off to google to figure out Pigments

There’s pigments for Casting resins, Resins, Acrylics, everything…..Except, a clearly stated pigment that’s suitable for 3D printer resin!

Infact, just what is 3D printer resin? what chemicals

I found this website which goes into some depth about resin types

Also found another website that does resin pigments in a range of RAL colours

BUT, they go on about Polyester, epoxy, and I’ve no idea if those things are compatible with the Anycubic resin i’m using

Another google and, I come up with a chemicals safety sheet for some Anycubic resins –

Listed there is a key component – which ends in “acrylate” and “diacrylate”…

so, looks like it’s an acrylic / acrylate based resin? can’t say i’m a chemistry expert but an Acrylate is a group of chemicals, so i’ll run with that

I need to look for pigments suitable for use in Acrylates!

But, err, is it an Acrylated Epoxy, or an Acrylated polyester, or even something else?

2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one is part of it!

Still clueless

https://pubchem.ncbi.nlm.nih.gov/compound/22019754#section=Depositor-Supplied-Patent-Identifiers

has some amazing information, including use in photosensitive resins

I’ve found a few websites that suggest urethrane acrylates are the go for UV resins

or, is it Acrylate polymers, or Epoxy Polymers!…….I’m leaning away from epoxy

SO, here goes – a quick google for Acrylate Polymer Pigment

I give up!. I’m just gonna buy a couple of bottles of ‘stuff’ and just see what works, This stuff seems to be recommended, and cheap, it’s brown and dyes resin, what can go wrong!

C64 Mini – Cheap and easy keycap ‘solution’

It’s taking ages to get progress on the 3D printed keycaps, I’m so close, but still have a few months of tweaking until I get it perfect enough to consider it a saleable item. watch this space 🙂

In the interim, I went and purchased a bunch of these

https://www.aliexpress.com/item/1005001616660795.html?spm=a2g0s.9042311.0.0.27424c4dI4vhMo

They’re a “100Pcs A28 Tactile Push Button Switch Cap 6*5.1mm Applies to 5.8*5.8 7*7 8*8 8.5*8.5 Self-Locking Switch Button Cap”

And, judge for yourself……

Old school!

Err.

Well, it’s more comfortable than nothing, and certainly opens up some options for unusual keyboards in the future 😛

yes, it’s not perfect, BUT for £1.68 you can have non painful pokey bits and actually do a reasonable job of typing on basic

or, splash out £3.36 and go for a dual colour like I did 😛

BONUS PRIZE TIME………………..

THE first person to order a kit and mention that they want these keycaps, I’ll chuck in a set of grey/black ones as pictured for nothing – I purchased enough to do properly do 2.5 keyboards, or 3 if you don’t mind a mix / match of black and grey!

Note, if you’re ordering your own keycaps off aliexpress, the internal dimension is key here, they fit, you can go a little smaller

the absolute maximum external dimension is 9mm, this leaves about 0.48mm clearance between keycaps.

Woo, Featured on Retro Recepies youtube!

That’s right, A few of you found me from Mr Perri Fractic’s channel on Youtube

The Video, 27 minutes in!, ME!!

There’ll be a little more coming up i’ve been told!

Highly recommend if you like anything slightly retro, give his channel a watch, superb production quality to it, great sense of humour and , generally seems to be a lovely chap that really brings out your inner childhood enthusiams for these weird old gadgets that a lot of us love.

Also, he’s getting close to 100,000 subscribers, so definitely is doing something right

Thanks Mr Fractic!

C64 Mini keycaps, Bleugh’s Log, date 12012021….second print!

This one went well 🙂

Note, the intentional ‘stone effect’ finish 😉

Most people would say this was caused by an over excited person, whom, upon waking early and discovering the complete print decided to not follow the correct drying / washing procedures in order to get it finished quickly!

I, err, disagree…

Either way, I now have a firm grasp of changes needed to the CAD model and also the supports needed in the slicer.

Those changes are fairly substantial, so I expect it’ll be a little while for my next update, happy to document them also if anyone’s interested.

Freshly dried and washed
Perfect size
A quick comparison

Keycaps progress! Still a long way to go….

Hot off the printer!
Somehow I lost the E again

Wow! An exciting day today.

After quite some nervous trepidation, I finally shoved some resin into the printer and achieved my first ever resin print.

And, amazingly, some stuff worked! Significantly more than I’d expected to work actually.

I’ve been quite ‘scared’ of actually starting a print, I‘ve read too much about toxicity and fumes, which aren’t things you want with two young kids.

Well, I spent a couple of hours doing some final reading, and setting up on the dining room table. Levelled the bed, levelled it again. Shoved in the resin and…a Spectacular success for me!

I know the print failed mainly due to poor supports, some text is also too fine. Both were concerns with the cad and the slicer and easily fixed 🙂 there’s probably a dozen other issues I’ve not found yet also (it’s been 30 minutes since I wash and cured them fresh off the printer)

Next step, iterating, optimising . It could be done in a few weeks at print 3, it could be print 10 and take a few months , but now I’m over the first hurdle, onwards and upwards!!

Here’s looking at U

C64 Mini Keycaps – Xmas CAD Milestone!

Doesn’t look like much. BUT

They’re all now working! I just need to tweak only 10 keys settings to significantly alter the entire keyboard – those 10 parent keys are copied through the rows

And I can now also alter all keyswitch holes simultaneously by changing two parameters.

Next step, latching mechanism in the holes (a small, sticky outy lump) and then figuring out how to print it!

Underside Wireframe view of the Return Key
Wireframe view showing the F Key Geometry

C64 Mini Keyboard – Small bit of Keycap Progress

It’s going to be a while yet, but I’ve finally fixed some long standing issues with the keyboard model i’ve been building in Fusion360

Doesn’t look like much!?

The main issue was a badly created model!. I’ve junked quite a lot and started back prior to when some odd dependencies crept in and really put some roadblocks on scaling things correctly and adding finishing touches.

But, it’s been worth it

That previous picture is the underside of the Keyboard – Those holes in the keys are 2.2 x 2.8 holes. it’s a first run at fitting the key switches into the keycaps. a lot more iteration needed to hollow it out a little and create some form of inbuilt snap-fit with stress relief, but…it’s a start!

The silver / grey keys over on the left are the ‘parent’ keys

If I make an update to the curves or size of a parent key – it rolls out to all the same sized keys in its row

if I need to iterate the hole size for the key switches, I simply change a few parameters for the hole size and it rolls out to all the keys in one go.

I’ve taken so long to develop it parametrically as it’ll now be so much quicker to iterate

Lots of parameters to change!

and, here’s a new render!……..going to spend the next few weeks iterating, and hopefully over Christmas , fire up the resin 3D printer for the first time!

C64 Mini Keyboard Kit – Contents

Just realised that it’s not easy to find an image to show what’s in a kit.

Here goes


what you need to add;

  • YOUR OWN KEYCAPS – Freshly butchered
  • plaster of paris / silicon for the mould
  • Solder
  • Glue

What’s In the Kit

  • 1 pre programmed arduino pro micro with headers
  • 70 normal switches
  • 1 locking switch
  • 70 diodes
  • 1 PCB
  • 1 USB hub
  • 1 4 core wire
  • 2 short USB cables one of which you cut the end off if you want, or cut / reuse the USB hub one)
  • 4 Screws (to help align the mould)
  • 1 3D printed plastic mould / jig to create a mould to put your keycaps on straight
  • 2 small pieces of heat shrink tubing

C64 Mini not included, but this is what yours will look like once you’ve assembled the kit

Coming at some point in the future (late 2021 at this rate) – 3D, resin printed Keycaps!

Another C64 Mini keyboard kit success

A very talented Hans Liss from the Facebook group – TheC64 Mini has make a perfect assembled kit.

Drool over the photos below

Note the extras like the hacked up USB hub to make it slimline

The Extra UART connector that he’s added, and the nigh on perfect Keybaord keycap butchery!

Hans also helped by pointing out a few errors i’ve made with the original firmware sent out with the kits. I spent a couple of weeks figuring out how to fix it and have a new HEX file for those that want it.

There’s still some ‘not quite exactly commodore’ quirkery happening – which i’m working on, but i’ll bet that 99% of you won’t be able to figure it out. I’ve only found out due to Hans’s extensive knowledge of the C64 inner workings and also me, downloading the original user manual for the Commodore 64.

C64 Mini Keyboard Kit – New Firmware available

New Firmware upgrade available

It’s been an intense and frustrating few months trying to figure out QMK in spare time here and there – today, something ‘clicked’ and…..I’ve made a new keymap.

Please email me – KEYBOARD AT BLEUGH DOT BIZ for a new HEX file. also happy to help you flashing the thing with the Arduino IDE (it’s quite easy!)

Why I developed a new keymap

A couple of users have reported that the key mapping is a little wrong when plugged into the mini.

By ‘key mapping’ it means, when you press a key, or combination of keys, you don’t get the character that’s shown on the keycap.

Most people will know this if they’ve ever used a US keyboard on a UK computer or vice versa, that Shift and 2 gets annoying after a while when you’re trying for the @ sign!

So, I’ve dun fixed those minor niggles that people observed….AND, i’ve gone and added quite a bit more!

Continue reading “C64 Mini Keyboard Kit – New Firmware available”

TheC64 mini Keybaord kit – a successful first build by a user

Batches 4 and 5 have started arriving! Here’s some pictures from a happy user who only received it a couple of days ago 🙂

Great soldering job 🙂

Good soldering job on the rear too.
Great use of the heat shrink to tidy the invisible mod up!

C64 mini keyboard kit – keycap butchery success!

Have been promising a long time to do this, so finally took a few hours to butcher another mini!

Some views are excellent
Another great view
And the worst view

As you can see, for the most part, it’s pretty good, but NOT perfect

what I’ve discovered…..

2 part epoxy works best

Each keycap row is a different depth – the top one needs the least glue, row 3 the most

My errors here. I used a hard plastic glue from Bostick. it doesn’t grip well enough on the top of the keyswitches. I glued everything, waited a few hours, half the keycaps didn’t stick

glued the rest, waited, half again didnt’ stick…rinse and repeat about 6 times, adding more glue till finally they all stuck.

The 2 part epoxy stuck fast and hard! – but I used too much.

The repeated adding of more glue caused the multiple key levels you can see in the picture

I’ll try one more time I think!

C64Mini keyboard kits shipped!

First batch of 15 kits shipped!

Postage on most was actually slightly cheaper than last time! But the two heaviest ones were more, the largest one was quite a bit more than anticipated…so it all averaged out ok…

One repeat customer has a couple of freebies, only one assembled this time!

Also my first ever customer finally will have a spare kit and some stuff to practice with 🙂

Next small batch is coming as soon as the 20cm USB cables arrive.

If you want a kit without the short, tidy looking USB cables then shout and I’ll do a small discount 🙂

Amusing story and reversed switches on the C64 mini keyboard kits

Correct orientation of the switches
Correct orientation from the top. (Except the shift lock…oops! That’s why I put extra switches in :-p)

A funny story about multi sourcing components and the importance of testing before shipping!

I used a supplier on Aliexpress to purchase a few thousand switches in a few orders over a few months but their prices went up quite drastically after the last order (doubled!!) they weren’t the cheapest to start with but were reliable and friendly, worth the extra ££

I found another supplier who did a good deal for a full bag of 4000! Ordered them and waited, very quick delivery and friendly also (will buy again!)

I built my first test new keyboard with the new PCB and switches

It didn’t work. Well, actually, it did! Work perfectly…but in reverse :-p …..

If you mashed every key simultaneously then only released the key you want to press….it worked!! Yeah, the supplier sent me 4000 ‘inverted’ switches! My fault for not checking prior to ordering, they ‘look the same’ so ‘must be the same’ was a wrong assumption on my part! (At least they all weren’t the shift lock type!!)

It’s a VERY easy fix though (found after several panicked hours of testing and building Keyboards)…rotate the switch 180 degrees and it’s perfect!

In each kit I’ve included a small errata note and list of basic instructions to help. It’s an annoyance but for you guys it really just means the silk screen doesn’t quite match the switch orientation so just ask first. Look at the pictures and of any doubt, email/messenger/twitter/Reddit me 🙂

C64 Mini Keyboard kits, ready to go :-)

I’ve a small batch of 14 kits assembled and ready to post 🙂

The ‘slightly open’ ones are waiting their 3D printed inserts which are taking about 6.5 hours for 3 right now 🙂

Send me a message if you are reading and would like one.

I have enough parts to make 50 kits all up, except for the USB cables – I’ve lost a large bag of them somewhere so have ordered more 🙂

C64 Mini Keyboard kit – a successful user :-)

By reddit user mfriethm. Looks amazing

I sold the first batch of kits mostly on Reddit

Over the past few weeks they’ve been making their way around the globe and I’ve had a lot of happy reports back

Today, Ive been able to relax finally, the Mould works 🙂

Reddit users fantastic gallery

He’s done an amazing job using a silicone mould!

The workflow – make a mould of your uncut keybaord

Cut the keys out, tidy them up

Place keys in mould

Put glue in keys

Place keyboard on top and use screws to align

Voila!

C64 mini Quick doodle for the USB hub mod

Had someone ask, so here’s a quick and rough explanation

You need to make SIX solder connections

First, lift the centre two pins of USB1 on the mini

Second, cut off the plug and solder four pins from the USB hub cable to the bottom of the USB1 connector pads on the PCB

Third, cut off the mini USB of the longer USB cable and create a bare end. Solder two data wires to the lifted pins on the mini’s USB connecote

This then attaches the USB hub in full to the minis processor

And just uses the physical connector on the mini as an extension of one of the sockets on the hub!

Assembly of the C64 Mini working keyboard kit! – PICTURES

Follows a couple of pictures of the install, I’ve also put a couple of videos up on youtube. More will follow

DIODE orientation. Note, make sure they’re all the same way round. One here isn’t!

I’ve put some videos up on youtube about the assembly process – the playlist is linked below

Putting the switches in Wonky for the first round of alignment (smt diodes hand soldered on the original prototype)

Make sure you solder the arduino headers on before you get this far with the switches

Back of board showing Diode legs clipped and only ONE switch pin tacked per switch

USB HUB TO FOLLOW – Pictures shown in blog previously if you need them quickly

Assembly of the C64 Mini working keyboard kit! – TEXT

Some quick steps right now – photos to follow.. Suggest have two tabs open, this one and the other PICTURES tab for reference

Some videos are up on youtube also

Link to Youtube videos

SUMMARY- SOLDER PARTS ONLY IN THIS ORDER

DIODES

ARDUINO HEADERS

SWITCHES

DIODES

  • Cut one leg shorter on the diodes – Use scissors . About 1-1.5cm is good
  • bend the short leg side to a right angle
    • Note the orientation of the diode – The F Key diodes have a diode picture on them. The white bar matches the location of the black bar on the diode.
  • put diode in holes and bend slightly to lock in
  • repeat for all diodes
  • Solder all diodes
  • clip the excess legs back
  • you have a few spare diodes so don’t be afraid to experiment on one or two to get the right bend / fit

ARDUINO HEADERS

  • Probably best to solder these in now before you forget
  • I’ve found it useful to PLACE the arduino on the headers (DO NOT SOLDER YET) so it keeps the headers parallel
  • Make sure the black part of the headers is on the underside of the PCB
  • Solder one pin of each header
  • remove arduino
  • finish soldering

SWITCHES – STEP 1, JUST TACKING IN PLACE

  • Pay attention to orientation
  • don’t worry about straightening the switches at this stage, the goal is to just ‘tack’ them in with a single solder blob to hold them in place. They can be wonky, it doesn’t matter.
  • DO NOT SOLDER MORE THAN 1 PIN OF EACH SWITCH IN ONE GO
    • The switches are easily heat damaged – they become ‘sticky’ and no longer move smoothly if the plastic is melted due to excessive heat. During the entire soldering procedure for the switches, do ONE leg, move to the next switch. when all are done, move back to the first switch and repeat.
    • I’ve damaged only 2 switches this way soldering the prototypes but it can happen if you’re not careful
    • Note that the white part of each switch is asymetrical. One side has a ‘dip’ / inset which guides the switch up and down. the other side is smooth
    • there’s a marking on the PCB to represent this dip / inset.
    • ALL switches go the same way
  • Get a sheet of paper
  • Insert the top row of switches into the PCB
  • Place PCB on sheet of paper and fold paper over the top, tightly
  • flip the PCB over
  • hopefully all the switches stay in place
  • Solder just ONE leg of each switch – any one – say the top right
  • Repeat for Row 2
  • DO NOT FORGET TO SOLDER THE ARDUINO HEADERS IN PLACE
  • Repeat for Row 3
  • DO NOT FORGET TO SOLDER THE ARDUINO HEADERS IN PLACE
  • Repeat for for row 4
  • (Hopefully you didn’t forget to solder the Arduino headers in place?)
  • and finally the space bar

SWITCHES – STEP 2, Straightening

  • This is probably the most important step to getting a good looking keyboard with all the switches aligned. Spend some time getting this right, you have a handful of ‘spare’ switches so now’s the time to make mistakes and fix them whilst there’s only a single solder blob on them
  • I’ll post a few videos shortly but there’s a technique.
  • Hold the board in the air
  • Use your index finger to push in, and slightly down on each switch whilst soldering the previous blob. The goal is to move the whole switch slightly so that it’s slightly at the top, or the bottom of its footprint.
  • when you melt the solder whilst pushing in and down, the switch will move slightly, sometimes you’ll hear a little click or snap as the solder melts
  • repeat this for each switch, pushing in and down slightly – when you look at the final position, there’ll be some of the pad visible at the top of each switch
  • NOW IS THE TIME TO TEST EACH SWITCH FOR SMOOTH MOVEMENT
    • of the 5 keyboards i’ve soldered, I’ve had two defective switches, this is partly the reason why there’s a few extras in the kit
    • of the 5 keyboards i’ve soldered, I’ve broken 3 switches by either over-heating, or trying to remove after putting them in backwards. unless you’ve got a hot air gun, they’re tricky to remove intact, hence check NOW whilst there’s only one solder blob!
  • When you get close to one side of the keyboard, you’ll have to fiddle a bit to keep pushing the switches in the same direction. I’ve found that changing technique a little and ‘flip’ the board lengthwise works. hold the board against yourself and use your thumb to pull the switch down instead of push
  • repeat the alignment technique for ALL switches!

SWITCHES – STEP 3, Final soldering

  • This is the easy / relaxing bit!
  • DO NOT SOLDER MORE THAN ONE LEG OF EACH SWITCH AT A TIME
  • do it by rows, clusters, however works for you, but here’s what worked for me
  • Solder ONE pad of each switch, then move to the next
  • once all switches are done, start from the beginning
  • Solder another pad, etc etc
    • A SMALL CHEAT – You only actually need to solder 3 points. Two on the ‘bottom’ of the switch – these are the electrical contacts. ONE on the ‘top’ – this is for mechanical stability. As you look at the keyboard, the bottom two pins are the important electrical ones. Pick any on the top
  • on my prototype, I found soldering all 6 pins tiring, so on my second version I just soldered 3 and it worked perfect. Up to you, but DONT SOLDER MORE THAN 1 PIN AT A TIME

Arduino

  • Note the orientation of the Arduino by the Small USB socket and a mark on the PCB. Also the silk screen on the PCB will match the letters on the Arduino.
  • these need a little more heat to solder to the pins

Finished Keyboard!!

The Hub

C64Mini working keyboard – The Butchery Part 2

Mmmm, Mini Cake’s been baked

A quick dry overnight and….It’s a success!.

BEFORE this point (or, worst case, at this point) I’d highly recommend you clean the keyboard thoroughly and go, purchase some clearcote / clear lacquer. I haven’t done it yet but will be spraying my next keyboard to get some longevity on the text and paint……...

The mould’s quite bubbly and not really useful for much other than being a support…But, if done with more care – who knows!, Maybe C64Mini Chocolate keyboards?

Next step, Power Tools!

ROUND 1

Mwahahahaha!

Still not entirely sure if it’s even possible to quickly and repeatedly butcher the C64Mini’s keyboard reliably with good quality.

For doing your own / one off’s, this step, you can take as long as you want. if you plan on doing a few though, taking a day or two individually dremmeling out the keys isn’t my idea of fun.

I do have a CNC – so, worst case I’ll have to learn how to actually use it, then I’d just need to make a protective jig, sit the keyboard on and just CNC the keys out. I’m not really in the mood to spend a few weekends firing that workflow up yet

Failure

The Angle grinder wasn’t really a success…..The blade’s too small and the sanding is going to be too uneven. There’s no way this will work .

Round 2………..

Larger surface area = larger chance of evenness?
Too much vibration

Ok, first thoughts, it seems to work, abeit slowly and with making my hand a bit sore….

new sandpaper should do it

At this point, I figured if I use something soft and large, I could hold the keyboard in place and sand it without hurting my hands so much…..

Puzzled over this one for quite a while till I looked down……..

Found an incredibly inefficient lawn cutting method! – Orbital sanding

Seems to have done the trick!…Pressing down into the grass holds the keyboard in place and also helps resist the vibration of the sander, making it sand more efficiently…………Win Win….Also i’ll patent pend using oribital sanders for domestic grass management.

But……

Poor Lawn

I moved to another bit of the lawn to avoid totally destroying a good bit of the grass…….I found that sanding till you can see the blacks of its eyes…….the lines between the keys seems to work well. At this step, you’ll want to remove as much material as possible to avoid so much processing / sanding later on

Do resist the urge to twist / remove the keys, try to let them come out almost by themselves

oops

At this point I’d realised that an average household lawn is actually quite abrasive..Have a look at the whiteness of the edges of the keys!

Oops! – ah well, this is why i’m experimenting, so you don’t have to. I’m going to run with the theme though -these keys look a bit battle worn now, no going back so i’ll probably add a similar theme to my C64mini case 🙂 will be good to relive the old days of creating scenery and my Warhammer 40,000 airbrushing . never really did play it, just enjoyed hacking up the plastics……..Anyways…

Keep sanding, get as much material off as you can (it will save a LOT of time later)

Once you’ve got them all separated, make sure to lay them all out in order so you can admire all the keyboardy keycappy goodness that’s resulted from the dismemberment of an innocent miniature recreation of an 80’s 8 bit home computer.

Eeeeeeeeeeeeeeeeeeeee

Now, go spending several hours in the garden trying to find the most commonly used letter in the English alphabet!

I’d neglected to factor in the ability of these tiny keycaps to fling themselves a considerable distance in various directions whilst being vibrated several hundred times per second.

Suffice to say, if you’re doing the same thing, try to do it in a location where the floors relatively clean and uncluttered

A colourblind person trying to find a brown keycap in a green lawn that’s not too long, but just long enough to expose the also brown ground beneath……..Yeah, not fun.

After an HOUR of searching though………………..Eeeeeeee….A full keyboard

full c64 mini keyboard keycaps!

Next step – post processing. Removing supports.

This step i’d say is the most important. Sand down a bit the bottom and curves of each key. Get rid of all the burrs, bits, etc. you won’t get much of a chance to do this once they’re stuck. Spend a lot of time on this, cleaning each key, just getting it ‘right’

Mini Mould All filled

Once your keys are all looking great and sanded, smooth – arrange them again into a the keyboard layout. Then, one by one, transfer them into the mould.

you’ll wanna make sure you get this part right 😛

I did them line by line, starting left to right. I also had taken a picture of the keyboard prior to refer to. Check twice, place once……………

Now i’ve realised that I haven’t actually considered how to stick these things in! – i’ll need to go research glue, D’oh! gotta pause this for another week of research and buying bits

C64Mini working keyboard – The Butchery Part 1

Time’s progressing and it’s still taking a long time to obtain a satisfactory print of my CAD keycaps. Some quotes have come in and…they’re quite a bit.

so, time to change focus for the short term to let me actually play games on the mini with all the keyboardy goodness that a working keyboard will allow

So, on to some butchering

The Plan….create a plaster of paris negative of the original keyboard – to hold the keys straight when attaching them.

Step 1 – Print out the case design from my last post

Fits like a glove……..or does it?

Step 2 – realise that I’m making a NEGATIVE and the keyboard needs to sit INSIDE the box, ‘upside down’ Redesign and re-print…

Better

Step 3 – Coat liberally in spray oil… Wife wasn’t too happy that I’d used her pricey artisnal olive oil from our trip to Italy, nothing but the best for my Mini though………

Step 4 – Knock up a batch of pancake batter Plaster of paris…About 50 grams of powder and 60ml water worked for mine….not too viscous.

fill the keyboard case just over 1/2 way to measure what you need

Step 5 – Fill up the mould

Screw on the keyboard – making sure the keys are aligned and straight with the F Keys and wait overnight…

Use the holes either side to top up the plaster so it overflows a little

Give the whole combo a dozen or so short sharp drops / knocks on the table to free up any air bubbles

Mmmmmmm….Keyboard Cake?

C64 Mini – Cutting the existing Keyboard Part 1

Did an attempt at a jig to make hacking up your own keyboard just a little easier….

it’s fairly easy to hack up the existing keyboard into bits….(get hacky thingy, cutty thingy, hack, cut…maybe smooth off burrs if you’re feeling artsy)

Getting the brand new hacked up bits of plastic that once looked like a keyboard to sit straight on the switches and resemble the previous keyboard resemblance …..not so much.

Turns out that making things ‘straight’ is hard……..so, some ideas

3D design and print new keycaps with locking mechanisms that work with my chosen keyswitches (still onging, it’s been MONTHS of work)

My first other idea…….. create a form to fill with plaster of paris, press the plastic full keyboard into that form, leave to set…

Remove keyboard and admire a perfect negative image of the keyboard.

Two things that could be done with this

Use that plaster of paris as a form to create resin keycaps (without any lettering) – I’m working on that!

second – it can be used as a perfect ‘form’ to sit the newly butchered keycaps in, fill with epoxy glue, sit keyboard PCB on top and let the keycaps become glued on, all nice and straight like!

it’s fairly easy to export the keyboard PCB outline from EasyEDA as a DXF then import to Fusion, extrude and…voila!

But…There’s an ever so tiny mistake in the image above

That’s the printed version…The holes line up great!

But….

Yeah, the keyboard should be face down!, D’oh!

i’ll see if the snips’ll work

The other thing….

Fits like a glove….

Nice and snug – Note the top row of keys is level…..

Some small design work needed but the idea has promise!. I just need to re-jig the hole widths a little to accommodate the angle of the keyboard better!

I’ve purchased another couple of C64 Minis so that I can improve this jig more. I’m not quite certain where the keys will ‘fall’ once they’re seperated from the base of the plastic moulding.

The more I think about it, i’m thinking that there could be a shedload more work in this jig – one ‘saving grace’ though – due to the way injection moulding works – there’s a slight taper on the existing fake switches. And, I suspect that the rear of them has been modded so that they’re almost perpendicular to the base. this will help the whole mould ‘pop off’ the injection machine…

That also helps me with this jig as it really means that, at the base of the keys, all the keys seem to have the same uniform rear rising, almost perpendicular taper and front curving taper. kinda like the below diagram

That could turn the whole change into just re-extruding the jig key holes at the 8 degree angle of the keyboard as above……..

C64 Mini Keyboard – More CAD

The first mediocre print!

It’s taking way too long, but I think I now have the lettering ‘just right’ – at least on the screen.

This was printed a bit too hastily at 0.08mm layer height on an Ender 3 printer. I’d used a brand new roll of untested filament and didn’t bother changing any settings. – it’s dimensionally ‘spot on’..

I’ve purchased a 0.2mm nozzle for my next trial , it’ll take ages but i’m hoping that those fine details on the characters come out a little better.

Why it’s taking so long……..

I’m learning as I go. I’m ‘tracing’ letters i’m finding on the net, creating them as a new sketch along the whole rows. There’s 4 differently angled rows so each needs to be extruded in a different direction to ‘cut’ the key.

This first run matches the C64 keyboard font as close as I can get. I’ll then ‘archive’ this layout for future use and create a second ‘3D print’ version.

This version will forgo the accuracy of the font and make features much wider, more rounded to allow the characters to come out better once 3D printed. The complex ones like ‘run stop’ won’t ever come out great on a standard filament printer, but the letters already come out pretty good…that’s a win for me!

a full keyboard!

The full keyboard is above – and you can see part of one of the adaptors i’m designing to click them onto the keyswitches. each keycap is hollow. that small grey part will sit inside the keycap

Where the time’s being spent…..

And finally – part of what’s taking so long.

Each key/character is taking on average about 1/2 an hour to an hour to design. Lets say 45 minutes.

65 keys to label

That’s a LOT of minutes…and i’m only getting an hour or two every few nights – a good solid weekend ‘free’ would be great and have this sorted.

On top of that labelling (which is now finished) I have to try to make each letter more legible and easier to 3D print. Generally that means ‘bevels’ everywhere – you can see above that i’ve done ‘Run Stop’ and ‘Shift Lock’ but SHIFT is still to do….it’s not as easy either as ‘copy, paste’ the Shift from Shift lock – that’s a different sized font on a different sketch plane.

Just one example of the issues I’m seeing…The Letter B

The Letter B – trying to create a fillet – rounding off the edges

The Letter B above has an issue with the geometry – just by the 0.1 – there’s a part internally up towards the arrow that shouldn’t be there – that’ll could play havoc with a slicer when set to really small layer heights

B – Alternate view

But, the Fillet also creates a zero thickness surface which looks unsightly and will probably cause issues if I don’t correct it now

So, Back to the sketch

Letter B – The Sketch

As you can see, i’ve kept the characters with few (if any) constraints. this way has been easier to freehand and eyeball as I can drag stuff around till it looks right by ‘locking and unlocking’ lines. most constraints used to create right angles, etc have been removed after to help with the process of making it 3D

Anyways, the ‘issue’ with the fillet seems to be around the place where the two control point splines meet – i’ve highlighted one in blue above.

I re-coincide each spline (have found deleting and un-deleting works, as well as hitting coincident )

That change should hopefully roll back up the timeline to allow me to make the fillet work.

To Create the key lettering I the character by 1mm elsewhere in my workspace, then move it to over the key.

Then extrude the face of the character into the key and ‘cut’ ….

this may seem odd, but it’s a really quick and easy way of consistently creating cutouts on a row of keys and making quick changes later.

That didn’t work, so, jump into surface mode – delete the entire inner arc of the B. Re-create the arc as a ‘patch’. Stitch together the lower part of the B. Then stich the whole keycap, then re-apply fillet and…..Voila…..3/4 an hour later, one filleted B…And a learned workflow if the same thing happens on another key!

Note, as-is, the keyboard fonts are a bit innacurate. I’ve sized everything based upon the smallest characters that need to fit – i.e. run stop, etc. The individual letters could be bigger – but any bigger and they’d look too big compared to those……….

Next steps,

DFM – Design for manufacture.

Just because you design a 3x2mm hole, doesn’t mean it’ll print at 3×2. Generally Filament printers do outer perimeters a little larger, inner perimeters a little smaller. The first few tests i’ve done now prove this. so, After a few months of ‘out of the box working’ on my Ender, I’ve finally gotta bite the bullet and calibrate it. The plan is to create an offset in the CAD file so that I still design the holes accurately based on measurement, BUT, can add a accurate ‘calibration figure’ Fudge figure to make them a little larger or smaller as necessary.

Right now my Printer is doing slightly oval prints – which should be easy enough to sort out if my D9 Adventures were anything to go by

C64 Mini Keyboard – Rev2 assembly

Lovely and sunny outside. I’m in the conservatory kinda enjoying the outside………
Through Hole Diodes should make for an easier assembling kit

My Kids hate me, my wife’s lonely but the march towards C64-Mini Keyboard workery continues – That and they let me have a few hours to tinker on the weekend!

Figured whilst assembling the new boards, I’d see just how long it takes to solder them….

Quite a while as it turns out

1/2 hour to solder in 65 through hole diodes

1 hour to solder 67 switches

another 1/2 hour testing and programming

So, about all up, we’re probably talking 2.5 hours for me to fully assemble one of these…….

Except, that 1/2 hour of testing and programming actually turned into a 5 hour ‘session’ of bug fixing / fault finding – one of which…..

One of these is not like the other………..

A back to front key causing lots of characters to repeat accross the screen…..M, Space – which are both on the same column of the matrix too!

Fixed that and have discovered that it’s not really possible to re-use the switches once you’ve soldered them in – UNLESS you use a hot air gun to remove them. I’ll definitley include a few ‘spares’ in each kit

The next problem – A sticky, grindy P key – I lifted a pad removing it , fortunately, the pad wasn’t electrically connected – only 2 actually are – which will save you some time! – just solder 3 holes for each switch – that’s 201 solder connections for switches instead of 402!

The next problem…the Fantastic QMK Just refused to work and compile 😦

Kept getting “qmk avrdude.exe: butterfly_recv(): programmer is not responding” the thing just wouldn’t work over USB like the others had

which turned out to be a couple of things.

You can’t use AVRDude when the Arduino IDE is open…

Arduino Leonardo type devices (well, the clones anyway) can be a bit finiky with the USB…

Generally sending them a ‘blink’ sketch does the job…BUT, they very often need a quick ‘double tap’ reset pin to ground whilst uploading……..that’s why I have a RESET header on this board – if you want to solder one in, feel free, it’s mainly to help me when developing it.

Another issue was the frequency setting in the rules.mk file – I’d previously used a 5V Arduino pro Micro (Atmega 32u4) , somehow a 3.3v one had snuck into my spares box – these run at 8MHz, not 16MHz

Changed the firmware, recompiled and……..It’s alive!

First row lined up – second just tacked on with a single joint, ready for lining up
Finally added a bit of heat shrink

Straight!, got the technique sorted – Note the two that are slightly ‘off’ to demonstrate what happens when you change the way you ‘hold’ the switches when flipping the PCB to solder

The case fits the keyboard like a glove!

Also got a bit of a chance to progress with the CAD……

This one day may turn out to look like pretty rough keycaps! mini ones! for a mini computer!

C64 Mini Keyboard Progress..

Rev 2 PCB’s have arrived – 15 of them!

Now waiting on enough Arduino Pro micros and switches to start making kits up!

Each DIY kit will probably contain the following – i’ll firm up with pictures once i’m done test populating a rev2 board

  • 70 Standard switches
  • 70 Diodes – Through hole (possible SMT option also depending on price)
  • 1 USB Hub
  • 1 PCB – Rev 2 or later
  • 1 USB cable
  • two small pieces of heatshrink tubing
  • a couple of pieces of wire
  • 1 Arduino Pro micro – Pre-programmed with QMK firmware and custom Keymaps
  • Some instructions
  • a set of FDM – Filament printed keyswitches – These probably won’t be ‘perfect’ so i’ll be chucking them in as effective freebies as I won’t be releasing the keycaps as a digital file.

About that last part – I’ve spent countless hours on creating these keycaps, and still have more to go. I’ll eventually release them as a Digital file, but for now, you’ll be able to at least use the freebies to see if new keycaps are for you.

If you wanted a professionally printed set, i’ll be arranging something with a printing bureau somehow… It’s also likely i’ll be able to source reasonably costed SLA resin prints of these…watch this space

And for the money shots…….I’ve finished the top row of key text!

Now I’ve gotten the first row done, the next three should be significantly quicker.

The text is recessed into the key by about 0.4-0.6mm – between 2 and 6 layers of 3D print, not really enough to be clearly felt – but enough to be ‘seen’

After that, there’s the optimisation for printing – Filleting the edges – trialling depths and generally finding out what actually works, looks and feels good

C64 Mini – Keyboard – More CAD…

Had quite a few odd issues with my old f1 key and trying to make a full keyboard from it using the same technique

…The main problem is that I can’t really remember what I did and in what order, and there’s some odd non-parallel lines that really should be – so I’ve started again from scratch

Turns out also that there’s a few types of keyboard out there, the C64-Mini isn’t quite 50% of the keyboard i’ve been referencing

Differences are only minor – BUT it does mean that an exact 50% scale won’t fit

So, Firstly I start with the side profile sketch again.

My revised Side View – I’m ignoring the space bar right now as it’s ‘different’

C64 Mini Keyboard – ‘Invisible’ fitting mod – Part Deux- More images

Not much of an update, I put a shorter USB cable inside so thought I’d take some pictures of the top of the USB cable wiring…..

img_0679

I’ve not installed heatshrink yet on the sticky-outy USB Pins – this WILL be needed to provide strain relief – being truthful, I hadn’t expected it to work first time so didn’t bother 🙂

img_0680

Showing the complete wiring –

Joystick USB port -> USB Hub ‘output’

Keyboard -> USB Hub ‘output’

C64Mini Circuit board -> USB Hub ‘input’

There’s two free internal USB sockets now!