Had a little play, using some SMT buttons i’m using in another project. These switches aren’t quite correct for this project – I need ‘square’ button-y bits and preferably ones with a small sticky-outy or inny bit that’ll let it capture a keycap straight.
Assuming the A500 Mini is 1/2 scale, like the C64Mini was then it’s looking good for keyboardification.
Half that gives about 235 x 162. take a bit off the 235 for the case thickness bit – gives 225. then height is set roughly by the number of keys ‘down’ and eyeballing the various membranes i’ve found!
However – I don’t know the internal space availability of the A500 yet – so plan going forward for now is to prototype as a 2 part PCB.
One design part of the C64 Mini keyboard kit I never really liked is the standalone Arduino Pro Micro mounted on the rear due to being no space. Adding it to the main PCB was also out of the question as the separate components would have been at least double that of a ‘cheap’ arduino.
I’ll keep a 31 way (ish) connector on the main keyboard part, so it essentially acts like a traditional Amiga Keyboard. I’ll then have a ‘special’ RP2040 based PCB that converts the Amiga matrix into USB for the A500.
I’m currently working on a design assuming I can use the same again. There’s very few switches on the market with a ‘square’ style centre part that can capture keycaps. I have leads on a few others, but plan this time is to find surface mount versions and try to get a batch ‘mass produced’ – i.e. little to no soldering needed for you lot!
Early days yet, it’s been quite hard to ‘get back into the grove’ . here’s hoping I get this finished in 2022!
Apolgies for any delays and people waiting on keycaps….
I believe I may have reached the end of life of my original Photon Mono printer. for the past couple of months, i’ve been having more and more print failures, and have had no idea why. I’ve approached the problem analytically to figure out what’s wrong
Where it started –
I had a proper working file that ‘just worked’ – exposure about 35s for the first layers and about 1.8s per other layer
That started failing a bit. some keys were printing incomplete. I increased the exposure slightly and success again.
More fails, this time the first layers were coming off the build plate. I increased the exposure for the first 4 layers and success again.
had many minor creeps of fails, up to now where i’m at around 50s for the first layers exposure and 2.2s per layer.
I figured maybe the temperature in the conservatory is too low – Nope, iterating a bunch of exposures with the printer near the radiator in the living room also had nothing but failures.
So, after a good 15 fails in a row, many caused my me experimenting with extremes, i’ve given up with the photon mono. There’s many things it could be, but I’m thinking it’s feasible that the LCD has finally ‘failed’. I’ve easily gotten 1500 hours of actual print time on the thing – well over 1000 will be just the production keycaps at 6.5 hours each!
And a few other things….all of which are quite finickitey and throw a wobbly at the slightest provocation! – Linux is fun eh!..
I’ll eventually get around to step-by step documenting and linking each step to ensure a good build environment so that others can duplicate what I’m doing
Once it’s all compiled, I drag the .uf2 file over to the pico (after holding bootsel whilst plugging it in) the thing reboots and becomes a keyboard
Ensure the Keymap is correct
Finish the basic keyboard layout, testing all basic keys
Introduce shifted keys
introduce ‘layers’ to ensure special keys are correct
introduce fancy stuff
Where this is going……………..The RP2040 Chip is fairly priced against the 32u4. I’m hoping that I can eventually switch the C64mini keyboard over to a fully SMT ready assembled kit – just add keycaps. And, i’m hoping I can do that for the Amiga Mini!, as much as I love soldering 600+ points, I appreciate some of you out there don’t!
And, I’ve another TOP SECRET project on the go also…It’ll blow yer mind! but, in 2022 that one, it’s a long burn that ‘looks’ finished (i’m holding it in my hands now!, all 2 circuit boards and about 100 3D printed pieces) but, needs quite a bit of work behind the scenes.
Also, Blinkenator, slow going, but I’m really trying, it’s just hard getting over this hurdle where it must be soldered….one last thing to try!
And, final before I go to bed, the C64 mini running the keybaord upgrade kit with pi Pico transplanted brains!
It’s being captured via a HDMI capture dongle and OBS studio so I can use my laptop as a test monitor!
There are only a couple of extremely tricky issues remaining now! they may need macros, and may not even be possible
Note with this firmware – It works perfectly with ENGLISH Language and UK Keyboard layout set in the firmware…
I hope to eventually be able to create more localised keymaps to change behaviour on boot so every language in the mini works well. IF there’s any pressing issues, please contact me, I should now be able to quickly and easily tweak a couple of keys for you.
Also, the Firmware will be part of the QMK Github soon, so you can download and tweak away yourselves!
To Upgrade your Keyboard, I’m finding QMK ToolBox to work brilliantly
Most older fimrwares out there will need to have B held down whilst shorting the reset jumper at the top of the keyboard inside , for whatever reason though t
I’ve found this a little flaky for whatever reason, sometimes mashing down every key whilst hitting reset does the trick
To make that more professional…….I now have configured the Bootmagic Lite.
To Update the firmware after this update, simply fire up QMK TOOLBOX, connect your keyboard to a Laptop. Hit ‘auto flash’, select the MCU (see picture above)…then Hold 1 and short the reset jumper inside the keyboard.
I’m still learning how configure all this, so bear with me, it’ll be slick just like those professional Mechanical Keyboards in no time*
*by ‘no tiime’ I mean potentially months and months as i’m tinkering in my limited spare time to add this extra functionality
and a few other C64 USB firmware’s i’ve found – these may have the bits needed to be able to get mine working much better – But, merging things is currently beyond my skillset – I’ll figure it out eventually
And, this awesome public project! – If you want a ready made USB interface – This looks great. Has some quite complex QMK mapping that i’ve not been able to understand – maybe it can be modded for my PCB!.
C:\1leo\arduino-leonardo-uploader-master\windows>testu Upgrade procedure starting. Missing parameter or file, you should provide the full filename of an existing .hex file you want to use.
C:\1leo\arduino-leonardo-uploader-master\windows>testu C64_default.hex Upgrade procedure starting. Com Port for Arduino device is detected as COM7. Reset Arduino into bootloader Com Port for Arduino bootloader device is detected as COM6.
Starting AVR Downloader/UploaDEr…..
Connecting to programmer: . Found programmer: Id = “CATERIN”; type = S Software Version = 1.0; No Hardware Version given. Programmer supports auto addr increment. Programmer supports buffered memory access with buffersize=128 bytes.
Programmer supports the following devices: Device code: 0x44
avrdude: AVR device initialized and ready to accept instructions
Mixing in an old batch of C64 Brown with the new Elegoo didn’t really work. I had 6 failures in a row – which i’d assumed was the FEP or me doing something silly / bad levelling . The 7th failure punctured the FEP! At that point i’d realised what i’d done (mixing all the stuff together) so, ordered some new Clear resin. I got a perfect print straight away!
The thing you see above is me, changing the supports (finally) after having issues with the old base layer being too thick and seperating from the build plate. I’d gotten around this by using longer base exposures, but still, had more failures than I’d like.
Hopefully now i’ve new FEP, new resin, and spent a couple of hours doing the supports properly, I’ll get a fresh print tomorrow!
My next issue – as you can see above…QMK. I spent weeks learning how to, and setting up QMK on my old laptop, which the kids smashed.
QMK has moved on a little it seems as now there’s a dedicated QMK MSYS32 installation…BUT, it doesn’t compile my old keyboard layout. if there’s anyone good with QMK out there, give me a shout!. I’ve no doubt I can get things working again to work on the code a little, just pressed for time for the next month or two and, i’m getting the coding itch this past few days 😛
If you’ve paid for a kit or just keycaps or waiting on spare parts, it’s now posted.
Missed the Saturday run to the post office so sorry about that.
I’ve now a small amount of stock of keycaps and plenty of kits so I can relax a little and have fun printing other stuff for a change! Can you believe that I’ve run at least 6L of resin through the printer …JUST developing and then selling these keycaps, I’ve never printed anything else on it 🙂
A quick pictorial ! on the process of creating keycaps.
I’ve missed out a few pictures, but this covers the basics. Using a timer, it’s around half hour all-up per keyboard. Sometimes a little more if a print fails!
Tried to make a ‘GOLD’ keyboard but need to research a little on how to keep the particles suspended. This one failed due to too much gold. It all sunk to the bottom causing layers to become underexposed and ultimately sticking to the FEP
Also tried to make a crystal clear keyboard…unfortunately I topped up the vat with a tiny bit of the gold mix from a poorly labelled bottle I use f or mixing (I didn’t write any label!) I’ll give these away with a kit to the first person that asks 🙂
Quite late into development, I’d realised that the F keys were supposed to be a different colour. So, I add two sets of F keys to kits. Some early ones went out without the extras. Happy to send some out if you shout.
Switches will be here in a day or two!, i’ll email everyone about kits shortly.
Purchased some ‘old gold’ pigment from https://www.resin8.co.uk/ and tried it with the keycaps for something different. Came out ‘ok’ – nice and gold on the top, but lacking in gold on the sides. I suspect the particles weren’t being agitated sufficiently and sank to the bottom.
I’ll try again soon with a higher concentration of pigment and see how that goes before considering offering these as a product!
I’ve now packed up 10 kits ready to be shipped and have emailed the first 10 people on the waiting list.
It’s been an expensive couple of months with the bad PCB’s and wrong arduinos, but, payday at the day job was two days ago, so i’ve already ordered enough additional parts to make everyone happy within a few weeks
I’ll work may way up through the waiting list and let you all know when I can finally make general stock available.
My New PCB’s will be here today! DHL shipping is expensive, but great when you need stuff quickly!
What this means – I should have general stock next week.
Timeline – I’ll get a test board built up this week. if that works, I’ll email out everyone who expressed an interest.
I’ll get everything kitted up through the week (time permitting) so I can get some posted this weekend.
The rest of the weekend will be spent kitting up everything I have so I can start selling again.
Sorry for the delay guys (and gals). Been a perfect storm of wrong components sent, big customs delays, non-functional PCB’s. I thought the ‘march’ timeline was generous and had plenty of padding in for worst case.
For general availability, i’ll be reviewing the price. Most things have gone up by over 20% in general (Brexit, Yaay), some have come down, and i’ve made some optimisations. These projects aren’t a get rich quick scheme for me, they’re just a way for me to get funds together to buy more tools and things to make more projects! It’s pretty much a cost neutral hobby 😛
One final update – Keycaps. I’ve started manufacturing and at the time of typing, I have sent out a few test items to kit owners. I’ll await some feedback before I can hit ‘go’ and make more.
Those are just some of the prints i’ve had to do to get to where I am now. This isn’t representative of the typical resin printing workflow. its generally a bit easier than this, BUT, I had to start from scratch, learning how to do everything, including stuff that hasn’t been done by others. AND I needed the base level print to be ‘perfect’ to avoid the need to paint them. There’s over 80 hours of actual printing time in this picture, on top of that, there’s the cleanup time, CAD time, setup time….these are the ‘successful’ failures, there’s almost as much again that i’ve binned due to total failures, where keycaps were unusuable for anything, not even experiments (as these ones have been used for). fortunatley most of those failures were caught early to avoid too much wasted resin….but when I get only 1 chance in the evenings on some days to quickly iterate, get the printer going, 1 failure can set me back a few days.
Anyways, now i’ve finalised everything……..
I’ve used an entire bottle of resin over the last couple of weeks making test manufacturing prints back to back to tune the process, changing nothing, just print, print, print… By that, I mean, it’s…
Remove Print, clean up
top up resin
Cure cleaned up print
repeat until bottle is empty
I’m now at about 70% success rate for good saleable keycaps. the other 20% have minor blotches or surface uniformity issues, so i’ll sell those discounted for those that are interested. I’m still getting about 1 in 1o that can’t be used in any way.
Good enough, and i’m sure i’ll get better as time goes on. Each print takes 6.5 hours – slow, but reliable and a 25uM layer height so about as good as it gets on resin printing for surface finish.
Each print also takes another 30 minutes or so to ‘turn around’ –
Remove from bed
set printer up again to print the next item
clean print (1 minute soak in IPA, then 5 minutes in ultrasonic bath then another couple of minutes under a warm running tap)
Dry Print – This is critical to good finishes. Some are taking up to 3 days, overnight in cardboard boxes near the radiator. I need to do a few checks in that time to ‘dab off’ excess moisture that leeches out of the print. Any moisture left on the tops of the keycaps alters the surface finish.
Cure print – this takes time also. I’ve found using UV lights (wash and cure station) warps the keys more often than not. Once the caps are dry, I leave them a couple of days in the conservatory. After that, i’ll blast them for a few minutes under UV light to finish the curing
Then it’s pack them up ready for posting!
And, Pack some up, ready for posting I have! I’ve done a mix of ‘on the supports’ and ‘loose in bags’ to see how these things go. I’ve posted a couple to myself via friends overseas to see if they survive!. once I know what i’m doing is working, I’ll make them available for sale!
8 sets of keycaps ready to go, waiting feedback from testers before I can ship!
The mechanical, fitty holey type tolerance, not the other type of ‘oh, that’s annoying, but i’ll put up with it’ type….
Here’s the keyswitch fitting into the space bar. zoom in. we’re talking fractions of a millimeter fit, which I can achieve consistently and reliably! there’s about 0.1 mm available on the sides with the latches and about 0.2mm availavle on the longer sides. the extra really being there to allow some grace when placing the keycap on to fit it. less clearance means it’s a royal pain to get the switch located into the hole.
BUT, the keys don’t ‘latch’ into place on the switches. So, to try to address that (if it’s even possible) i’m now adding a small feature
This is the underside of one of the ‘F’ Keys. That small part in blue is a 0.1mm ridge sat about 0.8mm up from the bottom and 1mm from the top. I’m hoping that will be enough to latch the keys on, AND allow ease of fitting without breaking the keycaps. Everything else is done now, this is the only barrier to releasing. I’ll run off a print tomorrow to see how it works out. I’ll run off further prints with this sticking out even more if i need to
Happy chappy this morning. They finished printing last night, my draining widget worked a treat – I’ll put a quick GIF up soon.
But, forgot about them until a mad panic at close to 1AM remembering I’d left them on the printer. With these, you can’t as the resin in the concave surfaces will part set in the morning and cause an uneven surface.
So, quickly washed them in IPA, regretted it immediately as it was dirty. Did another wash in IPA to clean the resin and straight to the hot water tap and larger bowl with a brush to clean off the bits. I’ll strain out the bowl later.
Final tweak needed now is the amount of grip to the switches themselves, shrinkage is variable at the moment, can’t go too small or keycaps may break when putting on, can’t go too big or they’ll be too wobbly and fall off.
May need to go middle ground and require a tiny blob of something sticky in each keycap, I’ll know soon enough!
The final hurdle for ‘good enough’ for me now is the space bar.
Every key prints lovely, except the largest one……Take a look
I’ve gotten all the ‘hard stuff’ over and done with first, or so I thought. Life’s taught me to generally avoid going for the low hanging fruit first, save the easy stuff for later when you need a boost.
Well, no matter what i’ve done (so far) in 12 iterations, have I been able to get a good looking space bar.
Now this has become my sole focus and roadblock for a successful print
Turns out that this is a combination of quite a few variables, I’ll list a few and probably follow up another time with clicky links and research
Exposure times are wrong –
They could be , I’ve really just gone and shoved stuff in to print and hoped for the best with standard settings. I Have now tweaked up the settings a little bit to 2.2s per layer due to mixing pigment in, and have had no real failures. I’ve also increased the first layers exposure times to 30s, still seeing minor issues there
FEP tension is wrong
Not really, This is a brand new printer, i’ve had zero catastrophic failures and have been overly cautious monitoring (and catching) early delamination from the print bed issues – Three times now
Possibly. I’ve 3 types (all anycubic) and seeing the same on all 3
Possibly, lots of people have been reporting issues in cold climates, I use the printer in the conservatory and it’s sub 10 degrees C in there regularly
Low temperatures cause increased viscosity and warpage issues with fine features from the FEP pulling them through the thicker resin
Too low exposure times on fine edges cause resin to cure, but not as hard as it should. So, when the layer sets on the bed, when it’s pulled off the FEP, it warps as it’s soft. This, I believe is causing the sagging issues i’m seeing on that space bar – it’s printed upside down, so the supports hold the points up, and between the walls sag, like an electric line held between two pylons
Probaly waaay too many supports, but this way, each ‘sag’ will be between supports that are just 1mm apart.
I’ve also nearly doubled the wall thickness to about 1.8mm – from 1mm
Hopefully now, this is the last step, Colour’s good, CAD is good, Supports are good.
I’ve ordered 2 Litres of clear resin ready to go and have a colour that’s not exact, but close and, importantly , very easy to re-create
Resin8 Earthy Brown, 3 ‘blobs’ of the end of a lollypop stick to 100ml of resin. and Black, 1 blob.
– The Rich brown used previously was too red. I’ll experiment a little with more black when running off the final tests
Has some successes with varying mixes of pigments! Wifey demanded I do a bronze one.
Fine adjustments needed only now and it’ll be a wrap.
….problem is, fine adjustments’ll probably take another 80% of the total :-p
Now, gotta figure out how to get Arduinos quickly as 50 wrong ones just turned up and due to Chinese New Year my expedited (expensive) DHL delivery won’t leave for a couple of weeks, D’oh! Best laid plans….
Well, final furlong for the 3D printing part anyway! Next step, investigating colouring in
Couple of successful prints! Rev 6 – just binging in stuff and hoping it works.
Rev 7 – more scientific and better CAD – all letters are now 0.2mm wider and deeper. This tiny tweak shows spectacularly well just how big a difference small changes can make.
Still some more CAD to do but soo close to final now!
And, finally, the print itself. I’ve learned that supports are critical here. Lots of them!
There’s actually as much material here in the supports as there is in the keycaps, but if you scrimp a little and try to reduce the amount, check out the top left of the picture below. I lost the return key and a few smaller keys were taken with it.
This was a calculated ‘risk’ by leaving this section to just have the standard auto generated supports, every other area had super dense supports.
There will be a middle ground, which I’m working on as I’d like to offer these cheaply…less resin used = cheaper to make!
Also, note the rest of the supports. THey are SO EASY to remove. When I offer these keycaps for sale, again to reduce cost, I’ll probably leave them as you see here. Makes for more robust packing and if you decide to paint them, you already have them held down on a convenient stand!
If that prints, I can try adding black pigment to make it darker brown.
If it doesn’t, I can try using a CMYK mix of colours to make the correct Brown
Once I get that shade, I can try different resin bases to see what gives the best finish! Maybe clear + brown or white +CMYK will do the job!
I’ll be iterating the CAD model and the colouring at the same time!
Hopefully this new CAD model will fix the minor offset issues with the keyboard, shifting all the keys slightly to the right also allowing me to finally reveal a working test fit!
One small thing I picked up when test fitting my first attempt, I’d not perfectly centred the left shift key button and Return buttons on the PCB. It doesn’t matter in the grand scheme of things as hacking your own keycaps doesn’t need perfect alignment on the wider keys, only the 1 wide keys
Where it is annoying though is I can’t correct this error or any keycaps I make now won’t perfectly align on old keyboards! Heh, what’s 1/2mm between friends eh!