Finally, afer YEARS of work, THOUSANDS of hours. One last CAD tweak was needed and the hardware side of this project is FINISHED…
Now, the project switches over to the wrapping up phase. I’ve gotta “cost” this to figure out what I need to sell it for so I can fund a swim in a Scrooge McDuck Money Bin
But, seriously, it’s now about sourcing packaging, accessories to present a ‘final’ item to you!
Once that’s done, it’s breaking out the spreadsheets, working out pricing breaks from suppliers and creating a couple of huge pots of custom pigment to colour resin!.
Once that’s done, it’s figuring out how to sell ém.
Before and after!…Caps Lock and % are now near perfect….the % is 2mm high,. Caps lock about 1.4mmThat’s less than 1/2mm on each side.
That lot doesn’t look like much has changed…..but, quite literally, EVERYTHING under the bonnet on these has changed.
We’re talking about 30 iterations – soon to be 32 to get to the same point that it looks like from last year!. I’ve held off printing the darker keys until I can get this right!
WHY, you may ask? –
well, it’s all about repeatability. If I order 100 PCB’s, I want to do everything possible to ensure I can actually make 100 keyboards.
Till now, adding the keycaps to the switches has been never quite ‘perfect’…during testing, I’d get the odd sticky key here or there, the odd ‘too loose’key here or there.
Here and there for your own projects is fine, But, if a tiny 1% of keys fail / become sticky, and there’s roughly 100 keys per keyboard…..it means almost every Amiga 500 mini keyboard produced will probably have a fault, and need re-working.
So, i’ve added features, made cutouts, tightened some, tolerances, loosened tolerances, edited the keycap text a little to make it clearer…HUNDREDS of hours of tweaking! (and about 4 liters of resin….)
Along the way, i’ve also had to iterate printing times / exposure times / UV light percentages. With such small features, too long an exposure obliterates the text. Too short an exposure fails the supports. Too much UV blurs the text, too little UV gives inconsistent print failures. With the custom pigment, i’ve settled on 55% UV and 1.9s exposure, along with wait times to reduce bubbles and to expose quickly before pigment settles……
The LAST thing I’ve now done -Reduced the switch openings another 0.12mm…now there’s just 0.08mm clearance on the long side of the switches to help keep them straight!.
it’s been a trade off for ‘stickiness’vs springback. Pushing the key down does give a tiny interference with the switch – this’ll loosen over time. BUT, Very soon, I’ll have the darker keys printed, and a PERFECT looking keyboard.
I know it’s taking a long time, but these lessons learned apply to ALL the other mini-keyboards, those’ll progress significantly quicker once this is finished
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