learning tower - furniture for children (woodworking, Assembly3)

[M4x]

Hey everybody,

I'd like to share my latest FreeCAD project which I also built myself in the "real world". It's a learning tower, which allows children to reach for example the height of the worktop and help in the kitchen. Or to reach the sink and brush their teeth like the adults.

The learning tower can be assembled in three different configurations:

1. Low standing height: 300 mm
2. Middle standing height: 400 mm
3. High standing height: 500 mm

The learning tower is made out of multiplex birch (ger: Multiplex Birke) with a thickness of 18 mm. In order to store the learning tower, it can be easily disassembled into its individual parts. The parts are mainly plates with a thickness of 18 to 36 mm (sidepanels with sidepanel bars).

The learning tower I've build is in use since May 2020. My daughter loves it!

In this post, I'm focusing on the FreeCAD part of the project. For further information, please have a look at the README. I'm also happy to answer any questions here which may arise.

The project is published under the CERN-OHL-S license. All files can be found here: https://gitlab.com/M4x__/learning-tower





Structure of the FreeCAD files

• learning_tower_components_FC0.19.FCStd: All single components and the corresponding TechDraw Pages
• learning_tower_assembly_FC0.19.FCStd: The full assembly, all subassemblies, the BOM and the corresponding TechDraw Pages. The components are linked into this file using App_Link
• learning_tower_assembly_Part-SimpleCopy_FC0.19.FCStd: Copies of the full assembly in all three configurations and the exploded assembly using Part SimpleCopy and the corresponding TechDraw Pages. This file also includes the BOM for the overview drawings. The BOM from learning_tower_assembly_FC0.19.FCStd is linked into this file using App_Link

Workbenches I've used (sorted alphabetically)

1. Assembly3_Workbench
2. Draft_Module
3. Part_Module
4. PartDesign_Workbench
5. Spreadsheet_Workbench
6. TechDraw_Workbench
   
   Things I'd do differently next time
   1. Get into Sketcher_CarbonCopy, PartDesign_Clone and PartDesign_ShapeBinder instead of recreating sketches for referencing purposes (I've done this because of little experience with these tools and fear of the Topological_naming_problem)
   2. For complex/hard to calculate technical drawings:
      • Export SVG from TechDraw pages in an early stage and use (for example) Inkscape to finish the drawing. Example: Drawing of the full assembly with a lot of Detail views. Export the drawing of the full assembly in the desired scale and in the scale of the detail views (it's possible to scale within Inkscape too). [wasn't necessary because the combination of Part_SimpleCopy and turn off "Keep updated" for the TechDraw pages until all detail views are set up, worked great!]
      • Increase the use of Part_SimpleCopy and Part_Compound to create objects to reference on. This can reduce the effort needed to calculate the TechDraw pages for FreeCAD/the system.
      • Use LibreCAD if the other approaches still take to long to calculate the drawing pages.
   3. Think a little bit more about PartDesign_Chamfer and PartDesign_Fillet and model them directly as part of the sketch if possible
   4. Use the Macro_EasyAlias (for Spreadsheets)
   5. Use the "[Macro] Snap Dimension lines to same length / re-center dimension"
   6. Use PartDesign_Mirrored. I haven't used this tool in this design because I thought that it wouldn't be of much use here. I can now say: I was wrong.
   7. Check if using the refine property on the last feature in the tree (per body) might be useful (for example to get rid of the lines on the surface of the part "sidepanel right" where the part "front panel" is going to be mounted). If you don't know what it is, take a look around the forum first and use this feature / setting with care!
   Things I'd do the same next time
   1. Use the Spreadsheet_Workbench and Expressions to make calculations and keep the design as parametric as possible.
   2. Use the Assembly3_Workbench.
   3. Export all drawings to PDF.
   4. Export all components to STEP.
   5. Make nice drawings using the TechDraw_Workbench.
   Possible further developments
   I'm not able to work on any of this ideas in the foreseeable future. But this might change at some point in the future and I'd like to have a place to pick my ideas up again. If you're interested in any of these, feel free to contribute!
   1. Use this as an example to get into photorealistic renderings using FreeCAD (Tutorial_FreeCAD_POV_ray).
   2. Use this as an example to get into FEM analysis using FreeCAD (FEM_Module).
   3. Use this as an example to get into the Animation_Workbench.
   4. Create a step by step guide to build this learning tower.
   5. Check out the Fasteners_Workbench and add the modeled screw and cross nut bolt to it, if needed / useful.
      
      Thank you!
      Thank you very much for this awesome software and very helpful community. I hope that I can give something back by sharing my files / this project.
      
      Designed in FreeCAD v0.19. Last used version:

      Code: Select all

      OS: Ubuntu 20.04.1 LTS (ubuntu:GNOME/ubuntu)
      Word size of OS: 64-bit
      Word size of FreeCAD: 64-bit
      Version: 0.19.22960 (Git) AppImage
      Build type: Release
      Branch: master
      Hash: c5a4b01d2e4218bcc0eb6650337650a6c65ef0e4
      Python version: 3.8.6
      Qt version: 5.12.5
      Coin version: 4.0.0
      OCC version: 7.4.0
      Locale: English/United States (en_US)
      

      Congratulations, if you've managed to read up to here

[mcdanlj]

Thank you so much for posting this! I've been working on a parametric appliance shelving unit to cut from baltic birch (probably also 18mm) and my design tree has evidence of my flailing around learning. I appreciate your sharing this to learn from, especially the explanations of what worked well and what you would do next time!

[M4x]

Thank you very much, I'm glad that it's helping you! Looking forward to your shelf project!

[mcdanlj]

I used my project as a way to compare working in SolidWorks and FreeCAD. I'm expert in neither so both show evidence that I don't know the best way to do things. I'm almost done with the assembled assembly (just some tedious placement to do) and was thinking about creating a separate assembly in which I pack the parts together for CNC routing. I'm currently racing the clock on a couple other projects right now, but I'm expecting to get back to this one pretty soon since I don't always have the pleasure of making something that my wife has specifically asked me to build. ☺

https://gitlab.com/mcdanlj/applianceshelf

[PAT64]

Hello sir
I would like to thank you for the publication of your realization, magnificent very complete work, it inspired me to build my tower, I adapted the dimensions according to the wooden planks that I had.
Thanks and bravo once again!