3d printing

Positron - an upside-down and portable 3D printer

I've been getting into 3D printing lately. I have an older Ender 3 V2 at home I bought during COVID. And in the past year I've acquired an Ender 3 S1, Bambu Labs P1S, and Prusa MK4.

I also dove head-first into 3D CAD, and designed a number of small SBC cases or parts to help with things around the house.

But I'd never built my own 3D printer from a kit—all the printers I've had were pre-built and at most, required assembling the prebuilt gantry or toolhead. That finally changed with the Positron V3.2:

Giving away 480 Raspberry Pis was harder than I expected

I gave away 480 Raspberry Pi Picos at Open Sauce last weekend, and ran into a number of challenges doing so. All of them self-inflicted, of course. I didn't want to just hand them out like candy—or, well... that's exactly what I did:

Raspberry PIZ Dispenser with little Star Wars PEZ Dispenser

My initial plan was to build a backpack mount for a full 480-Pico reel (they sell them in bulk like that, for pick-n-place machines). However, there was a major flaw with that design.

Constraints

I needed to get through TSA, so I could fly to San Francisco. Driving was out of the question, as my wife is almost full-term and I could not leave her for more than a week in the middle of summer, when the kids have about 15 events per week!

A full reel would require a knife or scissors, and I didn't want to check the bag whatever I built was in.

Modeling my Grandpa with 3D Photogrammetry

Today I released a video about how—and why—I 3D Printed my Grandpa and put him on my bottle of ketchup. Watch it here.

I sculpted a bust of my Grandpa in high school, gave it to my grandparents, got it back after he died and my Grandma moved out of her house (I wrote a tribute to my 'Grandpa Charlie'), and I kept on moving it around my office because I didn't have room for it:

Grandpa bust - terracotta by Jeff Geerling in 2001 - original statue
Grandpa by Jeff Geerling, terracotta, 2001.

I decided it had to go, but asked my extended family if anyone wanted the statue (thinking it would be sad to destroy it). One enterprising cousin suggested he could 'copy' the statue in smaller form using photogrammetry:

How to Export a 2D illustration of a 3D model in OpenSCAD

I've been getting into OpenSCAD lately—I'd rather wrestle with a text-based 3D modeling application for more dimensional models than fight with lockups of Fusion 360!

One thing I wanted to do recently was model a sheet-metal object that would be cut from a flat piece of sheet metal, then folded into its final form using a brake. Before 3D printing the final design, or cutting metal, I wanted to 'dry fit' my design to make sure my measurements were correct.

The idea was to print a to-scale line drawing of the part on my laser printer, cut it out, fold it, and check to make sure everything lined up correctly.

Some online utilities took an STL file and turned it into a PNG, but they weren't great and most wouldn't output a PNG with the exact dimensions as the model (they printed too big or too small).

Here was my model:

3D Model for Mounting Plate in OpenSCAD

My 6-node 1U Raspberry Pi rack mount Cluster

Now that I have a half-height rack and a 3D Printer, I figured I should finally move all my Raspberry Pis from sitting in odd places in my office to the rack. And what better way than to print my own 1U Raspberry Pi Rack mount unit?

6 Node Raspberry Pi 1U Rack Mount enclosure - 3D Printed for Pi 4 model B

The rack unit you see above was assembled from 6 'frames', 6 hot-swappable Pi carrier trays, 2 rack mount ears, and a couple lengths of threaded rod for rigidity.

It was printed from these plans from russross on Thingiverse; Russ Ross also made an assembly video, and shows how you can build a 2U 12-Pi enclosure using the same basic design, with interchangeable Pi trays!

Video

There is more detail and a full walkthrough of my home rack in this video:

Beautiful 3D Print time-lapses with my Nikon D700 and Octolapse

After seeing GreatScott's video on creating great 3D Printing timelapses, I knew I had to make better 3D Print timelapses using one of my DSLRs.

I had already tried using my pi-timelapse script with a Pi Zero W and the Camera Module v1 and v2, but the quality is just so-so, plus it's not synchronized with the 3D printer, therefore at least on the Ender 3 V2, the printed object goes all over the place:

Unstabilized Pi Timelapse of 3D Print on Ender 3 V2 without OctoPrint or Octolapse

What I wanted was a stable and sharp timelapse of the entire process with high enough resolution to use in HD videos I produce for my YouTube channel.

So how did I get it working with my old but trusty Nikon D700? Read on...