You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
120 lines
5.0 KiB
Markdown
120 lines
5.0 KiB
Markdown
# nakamochi 3D designs
|
|
|
|
the repo contains 3D models of parts used in the nakamochi project.
|
|
|
|
those design sources which are made with [freecad](https://freecad.org/)
|
|
use a version no older than v0.20. a stock installation of freecad should
|
|
be sufficient but you might want to install
|
|
[fasteners workbench](https://wiki.freecadweb.org/Fasteners_Workbench) if working on
|
|
a design assembly.
|
|
|
|
## DIY version (FFF)
|
|
|
|
fused filament fabrication design is suitable for 3D printing at home, located
|
|
in the [fff](fff/) directory. the main file is in [fff/provcase.FCStd](fff/provcase.FCStd).
|
|
"provcase" stands for "provisional case" because it was unclear at the time whether
|
|
this would have been the final version.
|
|
|
|
the project contains all the parts to make a full assembly with the following BOM:
|
|
|
|
- [raspberry pi 4 model b][rpi4]
|
|
- [waveshare 4.3inch DSI LCD][lcd]
|
|
- [sandisk portable 1TB SSD sdssde30-1t00][ssd]
|
|
- [joi-it armor "block" heatsink](https://joy-it.net/en/products/RB-AlucaseP4+07)
|
|
- 90 degree angle [USB-C adapter][usbc90deg] 3.1 gen 2, 10Gbps
|
|
- adhesive gasket/seal tape for LCD, 1mm thick, 10mm width, L370mm
|
|
- 4 screws M2.5 L16-18mm for heatsink mount
|
|
- 4 spacers 2-4mm thick depending on the heatsink mount screws length
|
|
- 4 adhesive bottom pads
|
|
- [enclosure main box](fff/box.stl), 3D-printed
|
|
- [enclosure side cup](fff/sidecup.stl), 3D-printed
|
|
|
|
all object constraints reference an embedded spreadsheet `params` to avoid
|
|
[topological naming problem](https://wiki.freecadweb.org/Topological_naming_problem).
|
|
prefer constraining against datum objects instead of faces and other elements produced
|
|
directly from sketches like pads.
|
|
|
|
finally, the [fff/provcase-assembly.FCStd](fff/provcase-assembly.FCStd) file contains
|
|
an "assembly" group. this is simply a collection of parts composed together to help
|
|
visualize how and whether all of them fit well together. it links to the provcase.FCStd,
|
|
so you'll need both files. this assembly group calculates all placement offsets from
|
|
`asmsheet` spreadsheet. here's how the assembly looks like:
|
|
|
|
|
|
|
---|---
|
|
 | 
|
|
|
|
the "assembly" std part has a custom property "view" with two options: exploded and
|
|
assembled. the property is configured from the same asmsheet.
|
|
|
|
### 3D printing the parts
|
|
|
|
> TODO: insert here acceptable 3D printer specs and an assembly guide
|
|
|
|
## DIY+ (plus)
|
|
|
|
this version features a custom heatsink combined with the bottom plate, suitable
|
|
for aluminium CNC milling. the construction provides a better heat dissipation
|
|
compared to the DIY (FFF) version.
|
|
|
|
|
|
|
---|---
|
|
 | 
|
|
 | 
|
|
|
|
<img alt="DIY+ temperature during IBD" src="diyplus/ir_1166.jpg" align="right">
|
|
the baseplate serving as a heatsink brings down the main CPU temperature
|
|
from around 70℃ to 50℃. when measured externally while doing bitcoin initial
|
|
blocks download, an IR camera showed around 36℃.
|
|
|
|
the main file [diyplus.FCStd](diyplus/diyplus.FCStd) contains all parts
|
|
as well as the assembly. other files in the [diyplus](diyplus/) directory are
|
|
exports from the main file, such as baseplate DXF, STL, STEP and drawings.
|
|
|
|
a complete assembly BOM is as follows.
|
|
|
|
**off the shelf parts**
|
|
|
|
- [raspberry pi 4 model b][rpi4]
|
|
- [waveshare 4.3inch DSI LCD][lcd]
|
|
- [sandisk portable 1TB SSD sdssde30-1t00][ssd]
|
|
- 90 degree angle [USB-C adapter][usbc90deg] 3.1 gen 2, 10Gbps
|
|
- adhesive gasket/seal tape for LCD, 1mm thick, 10mm width, L370mm
|
|
- 3 thermal pads 1.5mm thick, 424mm sq total area - see baseplate drawing
|
|
- 7 screws M2.5 L10mm
|
|
- 4 adhesive bottom pads Ø5mm, 3mm+ thick
|
|
|
|
[rpi4]: https://www.raspberrypi.com/products/raspberry-pi-4-model-b/
|
|
[lcd]: https://www.waveshare.com/wiki/4.3inch_DSI_LCD
|
|
[ssd]: https://www.westerndigital.com/en-in/products/portable-drives/sandisk-usb-3-2-ssd
|
|
[usbc90deg]: https://www.delock.de/produkt/65915/merkmale.html
|
|
|
|
other parts, harvested from the above list:
|
|
|
|
- 2 self-tapping screws 2.9mm L3mm (from the SSD)
|
|
- 1 screw M2.5 L5mm (from the LCD)
|
|
- 4 PCB standoffs M2.5 L30mm (from the LCD)
|
|
|
|
**custom parts**
|
|
|
|
- [baseplate](diyplus/baseplate_techdraw_c.pdf), CNC milled from aluminium
|
|
- [enclosure box](diyplus/box.stl), 3D-printed
|
|
- [SSD support plate](diyplus/ssdsupport.stl), 3D-printed
|
|
- 3 [spacers](diyplus/spacer_3x2.4mm.stl) Ø3mm hole, 2.4mm thick
|
|
|
|
> TODO: assembly instructions
|
|
|
|
## assets
|
|
|
|
various files are placed in the [assets](assets/) to use in an assembly composition.
|
|
for example, you'll find a 4.3inch display, raspberry pi 4 and a heatsink in there.
|
|
|
|
when creating a design assembly, make a new [std part](https://wiki.freecad.org/Std_Part)
|
|
group and import desired assets into it. if an asset is in a freecad file format,
|
|
open the file and drag&drop the top level object into the newly created std part.
|
|
then close the original file ignoring the changes.
|
|
|
|
## license
|
|
|
|
[CC-BY 4.0](https://creativecommons.org/licenses/by/4.0/)
|