Kris\Slyka

wheeee! I've successfully made a glass PCB! 0.1mm copper foil laminated onto a microscope slide using two component epoxy and a hot roller laminator, coated with cheap aliexpress dry film photo resist and etched in copper chloride.

turns out that most of my struggles during etching came from my bad exposure setup. The light source was way too diffuse and I way over exposed the photo resist. Going from 7.5 minute exposures down to 20 seconds really helped and switching from a very diffuse UV exposure box to a UV spot light mounted around 50cm away finally got me to an acceptable result.

Of course the one that ended up working was on my ugliest piece of copper on glass laminate but whatever. It finally works!

#diypcb #electronics

Jun 28 at 2:15pmWeb
Show threadLasse BeyerJun 28
@slyka amazing šŸ‘!
Show threadcrypticcelery @ WHY ā˜Žļø 2579Jun 28
@slyka ooh, that looks really cool! (including the process to get there)
Show threadTobias KlausmannJun 28
@slyka Very beautiful! As someone with no dexterity, are you planning an making this an entirely-SMD process? or asked another way: what would the story be fro through-hole components?
Show threadKris\SlykaJun 28
@klausman yeah, I think through holes would beā€¦ hard? Really really cool, but hard. I don't have much experience drilling glass but it seems like kind of a painā€¦
Show threadTobias KlausmannJun 28

@slyka I've done non-electronics glass drilling in the past and it's an exercise in coolant-coolant-coolant and "no, go slower". Plus, glass eats even diamond or carbide drills like there's no tomorrow (though in my past project, the glass type happened to be an especially nasty quartz glass, IIRC).

So, doable, sure, but probably not worth it. But now I wonder if there's another transparent material that's not as hard as glass, but can tolerate soldering heat (so no, not PMMA, PVC or anything).

Show threadKris\SlykaJun 28

@klausman I mean, "worth is" is very relative. Is it worth it to spend a week figuring out this whole process in the first place to make some pretty blinky stuff?

I mean, yes, obviously!

Show threadMattJun 28
@slyka That looks amazing, well done!
Show threadWolkensteineJun 28
@slyka
This is so cool!
Stuff which looks cool AND works, is just amazing. What cool project!
Show threadMiraJun 28

@slyka So very cool! Itā€™s great to see the progression as you worked out the process.

What you making? Given the amount of remaining copper, is it a RF board?

Show threadKris\SlykaJun 28
@mira hah, nah! It's just a little LED blinky thing for testing since I had no idea if this would even work. Just a little LFSR with some LEDs hooked up to it
Show threadMiraJun 28
@slyka Looking forward to the finished project
Show thread0xC01DC0FFEE ā‡’ EFJun 28
@slyka that's really cool. I've been looking for a process to do that for a while. It looks like there is a lot of adhesive residue left on the glass left, though. I wonder whether someone has had success with diy electroplating glass for that purpose
Show threadKris\SlykaJun 28
@0xC01DC0FFEE yeah, I've had some success just scrubbing the leftover epoxy off with acetone and a toothbrush but it's a lot of work. And at some point you're probably gonna start delaminating stuff. It might be better to just use a clear epoxy and make sure you get a really nice and even layer and then leave it alone.
Show threadkwayk42Jun 28
@slyka
Show threadKris\SlykaJun 28
@kwayk42 me tooo!
Show threadkwayk42Jun 28
@slyka are the functional, or just fabulous?
Show threadKris\SlykaJun 28
@kwayk42 we'll find out in 3-4 days when the parts to populate them arrive!
Show threadWilfried KlaebeJun 28
@slyka Would it be possible to "etch" the copper with a laser cutter?
Show threadKris\SlykaJun 28
@wonka maybe with a fiber laser? probably not with anything else, at least not directly. You might be able to put on an etch resist, laser that (either ablating it or exposing it) and then etch normally. @breakingtaps seems like the kinda person who would know about that.
Show threadMarsh RayJun 28

@slyka @wonka @breakingtaps Copper is just super reflective at most wavelengths. Literally used for laser mirrors.

You could also use the photoresist to selectively tin (or gold) plate the copper, then use that as a resist for whatever subsequent processing.

I bet a glass/gold/patina art piece could look *amazing*

Show threadKris\SlykaJun 28
@marshray I'd love to do ENIG on these but that seemsā€¦ tricky to do at home. But I also really like the look of copper patina
Show threadNina KalininaJun 28
@slyka congratulations, great job! I don't believe I've read anywhere why glass; it isn't a very shock resistant material, and it's a pain to drill, though it's a great insulator. Would other material work for your purposes?
Show threadKris\SlykaJun 28
@nina_kali_nina well, the purpose is mainly "it looks cool" soā€¦ idunno?! As far as actual PCB materials go it's probably not actually very useful
Show threadNina KalininaJun 28
@slyka I believe it is useful! Fighting a good base layer material is so difficult :(
Show threadKris\SlykaJun 28
@nina_kali_nina yeahā€¦ I'd love to figure out how to make my own bakelite or something!
Show threadMethylzeroJun 28
@slyka @nina_kali_nina Step 1 should be finding an excellently ventilated area, ideally outdoors with non-zero wind. Neither phenol or formaldehyde are friendly to living things.
Show threadKris\SlykaJun 28
@Methylzero @nina_kali_nina well, the very first step would be to build a bakelizer. And if you've gotten to that point I feel like there is probably at least a proper fume hood and PPE involved.
Show threadmmu_manJul 6
@slyka @nina_kali_nina wondering if galalithe is conductiveā€¦
Show threadNina KalininaJul 6
@mmu_man @slyka it shouldn't be
Show threadNina KalininaJul 6
@mmu_man @slyka here's a page from a reference book
Show threadKris\SlykaJul 6
@mmu_man @nina_kali_nina I think I prefer my PCBs to be veganā€¦
Show threadNina KalininaJul 6
@slyka @mmu_man <3
Show threaddiana šŸ³ļøā€āš§ļøšŸ¦‹šŸŒ±Jun 28

@nina_kali_nina @slyka

Let me tell you about Borosilicate Glass Microscope Slides šŸ˜ø

Heat resistant and durable!

Show threadParttimesailorJun 28
@slyka this could come in handy after the apocalypse.
Show threadParttimesailorJun 28
@slyka itā€™s also very cool.
Show threadRaykoJun 28
@slyka That's pretty cool looking for a PCB, never seen one made on glass. Wouldn't it be risky to solder on though?
Show threadKris\SlykaJun 28
@rayko I've ordered some low temperature solder paste and I'm gonna reflow solder it to meet this heating as even as possible. We'll see what happens!
Show threadLou šŸ”ŖšŸŒžJun 28
@slyka I guess it's one sided? šŸ˜…

congrats, looks v clean
Show threadKris\SlykaJun 28
@kouett at least until I can figure out how to drill vias into glassā€¦
Show threadAxel HartmannJun 28

@slyka - congratulations and thank you for the perseverance!

What does it look like from the other side of the glass? Have you got a photo of the reverse side? Is the epoxy very visible?

Come to think of it, at one of the previous CCC Congresses, a genious tinkerer showed how to make electronics by taping copper tape to wooden sticks (tongue depressors, kind if like oversize ice cream sticks), along with clips, button cell batteries, and LEDs with "legs".
I wonder if this self-adhesive copper tape would work & be etchable...?!?

Show threadAxel HartmannJun 28
@slyka
Show threadKris\SlykaJun 28
@axel_hartmann I have some previous posts that show the backsides. They look fine. The epoxy is transparent and basically invisible from the back. This whole thing actually started out with me just sticking some copper tape to a microscope slide, but the glue on the tape does not hold up to the etchant and it just comes apart unfortunately
Show threadAxel HartmannJun 28

@slyka - and I was convinced that I had followed this thread in its entirety - thanks for the pointer.

Somehow I envision a set of 6 making up a lampshade with LEDs soldered to the inside, projecting through the holes of the other panes...

Show threadjasegJun 28
@axel_hartmann @slyka I did some moderately complex circuits with copper tape on cardboard before. The good copper tape has a very thin prepreg (epoxy/glass fiber) backing layer that helps stop it from tearing.
Show threadQuixoticgeekJun 28
@slyka that's awesome! Are there any issues with heat when soldering?
Show threadKris\SlykaJun 28
@quixoticgeek I don't know yet. Currently waiting for low temp solder paste and parts to get here.
Show threadDr David MillsJun 28
@slyka win!
Show threadShadSterlingJun 28
@slyka this may be a little beside the point, but that also strikes me as less toxic to recycle than conventional PCBs
Show threadKris\SlykaJun 28

@ShadSterling unfortunately also a lot less useful :|

would be nice if I could replace the epoxy holding the copper to the glass with something less nasty

Show threadJeff RizzoJun 28
@slyka that looks really cool! Do you need to solder the entire "board" at once to keep differential heating from cracking the glass?
Show threadKris\SlykaJun 28
@jeffrizzo dunno yet, but I'm gonna reflow solder it on a hotplate anyways
Show threadDEVilonger šŸ“ŸšŸŽ€Jun 28
@slyka cool!
Show threadJohn "Dobbymoodge" LambJun 28
@slyka ok, you have to do this on something like an old wine bottle. You could cut the top off and put it on a turntable with a light inside so you get blinkenlights *and* the old hippy shadow/light projection visuals.
Show threadKris\SlykaJun 28
@dobbymoodge yeah, that'd be super cool. No idea how I'd do the laminating step though since it's hard to fit a wine bottle through a laminatorā€¦ maybe some kinda custom shaped press thing or a vacuum bag situationā€¦
Show thread0xC0DEC0DE07E9Jun 28
@slyka those look really fucking cool
Show threadKris\SlykaJun 28
@c0dec0dec0de thanks! ^-^
Show threadIrenes (many)Jun 28
@slyka grats!!!!! how cool!!!!
Show threadShae ErissonJun 28
@slyka wow it looks great!
Show threaddoragasuJun 28
@slyka Very cool, congrats!
Show threadVincent SparksJun 28
@slyka I'm going to guess that that board is a 555 driven binary counter? The SMD bridges over the traces look like spots for resistors and the SMD spots that go to ground from there look like spots for LEDs, am I right?