19. Project Development¶
What tasks have been completed¶
In 2020 the entire machine has been designed in Onshape as a 3D parametric assembly model complete with movement limits. The entire machine has been assembled and tested with four complete sets of parts for, Foam 2020 Fab Academy Glasses, 727 Airliner Model Glider, 1.2 meter wingspan Sci Glider Model Aircraft, and 4 alignment and run out test cut plates in XPS foam.
In 2022 a custom design circuit board called the 3PakCNC was completed and is operational allowing control of the foam crawler via a web based control hosted locally on a ESP32 microcontroller. This allows g-code to be stored and run from a SD card on the 3PakCNC board locally.
What tasks remain¶
In 2020 a off the shelf control was used.
In 2022 a the custom 3PakCNC control was designed, fabbed and programmed, this left no tasks remaining.
A complete BOM for 2022, the complete BOM was completed in 2022.
What has worked¶
The Onshape as a 3D parametric assembly model was a godsend to the assembly process. 3D printing was extremely useful to quickly iterate improvements and corrections to the Foam Crawler. MakerSlide worked extremely well as a structural frame element and for linear motion.
What hasn’t worked?¶
The gear ratio for the Y roller axis needs to be optimized for power and resolution. Y axis cuts are jerky revealing steps as small raster line like serrations in diagonal cuts.
The electronics housing is just awful to assemble and work in. The electronics housing needs a design overhaul to address these two major issues. The electronics housing may be better located on the right side of the machine in housing similar to the left mechanical cover.
The power supplies should;d be moved off the back of the Foam Crawler and may be better located on the bottom of the machine possibly between the aluminum extrusions.
The X axis MakerSlide is susceptible to flexing, which is not and issue in foam, but if harder materials are to be cut back to back maker slide (double up) may be needed to mill harder materials like wood etc.
What questions need to be resolved?¶
Does anyone want to build a foam crawler. Doe people see the advantage of a foam sheet milling machine. Would people rather cut foam with a hot wire CNC? Can good quality metal castings be made with foam patterns made from foam crawler cut parts? Can I sustain the momentum after fab academy to improve the foam crawler’s performance, usability, and human machine interactivity.
What will happen when?¶
In 2020 a working foam crawler with commercial control board was demonstrated,
In 2022 a speeds and deeds optimized foam crawler with custom designed 3PakCNC control demonstrated production quality foam cutting of three complete sheets of material to assemble and build the SciGlider 1.2 meter model glider!
What have you learned?¶
In 2020: What it takes to custom design, assemble, and document the mechanicals of a CNC machine.
In 2022: What it takes to custom design, stuff, program and document a custom 3 axis CNC control.