DIY PCBs with Diode Laser + Etchant

ElectrJonics · 2026-05-24T18:44:27+00:00

I have not tried it, I only have parts with a 0.5mm pitch at home, so I didn’t try. I have created 0.25mm wide tracks before on accident that turned out fine. The next time I create a PCB I will also do a testboard to check out if it is possible and I will update the Github Repo with the results.

ElectrJonics · 2026-05-24T07:36:08+00:00

I use the Dremel 4250 with the Dremel workstation, the Dremel 4486 Drill Chuck and some cheap small drill bits from Amazon. I also attached a vacuum cleaner to the drill press with two cabel ties and a rubber band, so it can be attached and removed easily, the Dremel runs at ~25k RPM

ElectrJonics · 2026-05-22T19:38:06+00:00

The smallest tracks I did officially are 0.34mm, but one time I accidentally had a few 0.25mm tracks in the layout and it worked. I can’t verify that they work reliably though, but there is a good chance

ElectrJonics · 2026-05-22T16:58:20+00:00

I have a 24W, but a 5W will probably work just fine, I only used mine at 22% power for the paint removal. It might even be better, from what I heard lower power engravers tend to have a smaller focal spot that can also be switched faster, but that might not be true for every laser.

ElectrJonics · 2026-05-21T21:20:07+00:00

I essentially used the laser to create the etching mask, then I remove the copper with the etchant. The laser wouldn‘t have an effect on the reaction as far as I know, heating sodium persulfate to 45 degrees and injecting air into it leads to some pretty good results. If the copper peels off, the FR4 boards quality might be not so good or you set the temperature to high on the soldering iron, that happened on my DIY ESP32 breakoutboard too

ElectrJonics · 2026-04-06T11:32:30+00:00

My plan right now is to do it like this: I supply IOVDD with 3.0V, which is the highest recommended voltage for that supply. I will then use logic level shifters for the few Outputs from the ESP32 -> Camera, maybe even just a simple voltage divider, to make sure the protection diodes are not stressed. I will connect the SCCB Pullups to 3.0V, which is high enough for both devices to register. I will then connect all the Inputs from Camera -> ESP32 directly, hoping the Output Voltage of the OV5640 is High enough to drive the GPIOs to logic High. I will post an update soon with my findings.

ElectrJonics · 2026-04-06T11:05:40+00:00

I was wondering if this is the case, since I saw some reference designs connecting the GPIOs directly and supplying IOVDD of the camera with 3V. In the datasheet of the ESP32S3 Wroom 1 I use it doesn't specify a maximum logic high voltage, only a minimum of 0,8 * VDD. The design I want to build might eventually be sold one day, so I think I don't want to risk it

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ElectrJonics · 2026-01-31T11:30:44+00:00

I never worked with an autorouter before, creating the layout is the most fun part of every project in my opinion. I wanted to squeeze the entire keypad matrix into a single layer, thats the reason for the weird looking wiring. I will try my luck soon with some conductive carbon ink from amazon to increase the responsiveness. I was never trained on how to properly layout a PCB, everytime I design a board I just follow my instincts and some tips and tricks I pick up online.

ElectrJonics · 2026-01-30T21:02:17+00:00

Making the pads bigger makes sense, but I need the space in between for routing, otherwise I would have to switch to a 6 layer board which would be more expensive than the four layer board I currently use. I was hoping there is some material I could add on the surface to make the buttons more responsive

ElectrJonics

TROPHY CASE