Building my own PCBs

A project log for Atomic Force Microscope - from ground up

The aim of this project is to make high grade all diy AFM.

100dollarhacker100dollarhacker 12/06/2023 at 14:440 Comments

It may sound like going two steps back, but it worth it. One of the problem with such projects is that they're hard to reproduce. It is hard to do such project with breadboard. I've tried and burned my charge pump(single to double rail dc-dc converter) since I moved wrong resistor in the jungle of resistors on the output stage.

So, I needed to go back to the beginning and do it right. I thought of printing delicate SMD connector using laser module and on 3D printer but it creates dangerous fumes, arrr... Then I've stumbled on video about creating SMD with CNC 3018, WHAT?! Is it even possible? I had to check it out.

My old cheap 3018 CNC, had controller damaged so I had to replace with even cheaper CNC shield v3 that was laying around idle. After connecting/compiling/installing/tuning I finally got my CNC back.

Ugly but doing it's job.

Now I started to play with height map, it's important for such delicate components like 0.5mm pitched SMDs. 

After some tuning on the fly, I got my first SMD connector.

This is a test of LTC3260 0.65mm pitched layout

It's promising especially given the fact that it was made with old and bit broken bit. Results can be improved even further. 

Now, PCB can be created in matter of hours and I don't have to wait two weeks for each PCB iteration.

It was worth the time invested 😀

After inserting new/sharp bit I got quite satisfying results

It good for development, the final board will be printed using one of many fabs out there, that print PCBs.

Now let's run example with 0.5mm pitch

Not bad for standard 30° bit. I guess 20° or 15° can make even better resulta. 

In order to use high precision for my PCB, I used DRV8825 motor drivers. With setup of 1/32 step. But it got it's price, drivers got super hot and I got automatic shutdown. To prevent this I printed this nice box and vent to cool down everything. 

Another necessary step back from my cause.