From a Pile of Dead 3D Printers, One Maker Built a Robot That Captures Detail No Single Shot Can Reach

Alan of the MandicReally channel needed consistent, high-resolution close-ups of 3D printer nozzles and hot ends. Every tiny surface mark and wear pattern mattered for his Mandic Labs work, yet standard microscope shots left large portions blurred. Focus stacking solves that by shooting the same subject many times at different focus depths and merging the sharp areas later. Doing the job by hand quickly becomes impractical. The microscope’s own focus ring lacks the precision and repeatability required, and even small shifts in framing or angle ruin the stack.

He overcame the challenge by creating a unique motion platform based on a secondhand desktop microscope. The machine moves the entire microscope up and down in tiny increments while the subject stays anchored to a robust platform, and for horizontal adjustment, all he has to do is touch a small knob to center any tiny bit without disturbing the microscope itself. The end result is a succession of photographs that software can combine into a single outstanding sharp snapshot, even if each individual shot would be unsteady on its own.

The majority of the components for the robot were items he already had on hand. An outdated, discontinued Creality Ender 3 donated its main brain and screen. He got lucky and picked up a few sets of linear rails from a previous machine he’d built, allowing the contraption to move smoothly. Some stepper motors and lead screws were just taking up space in his storage bins, and he’d printed the moving parts with stiff carbon-fiber filled filament to avoid flexing and blurring the photos. The foundation is made of a leftover laser-cut acrylic sheet recovered from neighbor’s trash, and some aluminum extrusion creates a strong frame that sits on rubber feet to prevent vibrations.

It’s a two-axis system, with the vertical bit using a TR8x4 leadscrew and a NEMA 17 motor to lift and lower the microscope in tiny chunks, as small as 0.02mm if you can believe it. That’s ideal for the extremely small depth of field achieved at high magnification. The X axis just pushes the object sideways for a moment, allowing him to properly center it. Both axes run Marlin firmware, which he placed into the old Ender 3 brain, and there’s a vintage RepRap screen with an encoder wheel, so all he needs to do is set the total trip distance and step size, then click start.

To ensure even illumination, the lighting is coordinated utilizing a pair of white LED strips. An extra ESP32 board running WLED firmware powers several addressable RGB LEDs, which not only offer a clean visual accent to the system but also provide useful backlighting via the acrylic base. A simple 24-volt supply powers the device, which is housed in a small, neat container. Once the firmware is in order, getting the thing to work is simple. So all he has to do is set the step distance and total range on the screen, place the microscope over the subject, and push go. Each time it stops, it takes another picture, and after a while, the stacking software can combine them all into a nice photo with sharp and clear details.
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