this post was submitted on 15 Jul 2026
35 points (94.9% liked)

Ask Electronics

4220 readers
46 users here now

For questions about component-level electronic circuits, tools and equipment.

Rules

1: Be nice.

2: Be on-topic (eg: Electronic, not electrical).

3: No commercial stuff, buying, selling or valuations.

4: Be safe.


founded 3 years ago
MODERATORS
 

Which do you prefer? I have the option to do both but milling seems to take awfully long and produces a lot of noise and glass fiber dust. It has the benefit of not needing etch resist which is also messy.

Chemical etching with iron chloride is also quite messy. First applying etch resist, removing part of it, etching etc. It is much simpler though and you don't need a CNC machine for this.

you are viewing a single comment's thread
view the rest of the comments
[–] Rolive@discuss.tchncs.de 2 points 2 weeks ago (1 children)

Hmm. I've gotten to the point where I used my CNC for the chemical etching process as well. Instead of fumbling with toner transfer I use spraypaint and a laser engraver as etch resist. It is way more reliable.

As for ferric chloride, indeed you cannot see your circuit board but it is possible to store this for long. Solutions like HCl + H2O2 don't last very long and I only do PCB making sporadically.

[–] RedBauble@sh.itjust.works 1 points 2 weeks ago (1 children)

This is basically what I do at the FabLab, I was about to post a comment when I saw yours. If you're interested, I wrote a blog post on the procedure, what I need to update it for double sided PCBs https://emamaker.com/projects/fablab/pcb-laser-engraver.html

[–] Rolive@discuss.tchncs.de 1 points 2 weeks ago (1 children)

Interesting read! I've seen a video on youtube where someone used white UV curing resin as the first layer and also as etch resist. It can be cleaned with IPA and you just leave it on after etching.

Afterwards a green layer of UV curing resin is applied and the laser is used to burn away only the green material so that silkscreen text becomes visible. I haven't tried it myself but it looks like a promising process.

[–] RedBauble@sh.itjust.works 1 points 2 weeks ago

Yeah I know about that kind of approaches but I haven't been able to test them, the resins don't look cheap and I don't make pcbs often enough to justify the cost. But I have tried engraving FR4 to get silkscreens on single sided boards. Decent results, but the smell is awful