A few weeks ago I was contacted through 3D hubs by Quinten van Alphen, a student at Industrial Engineering and Management at the Fontys Technical University of Applied Sciences in Eindhoven. Together with a few other students they worked on a project “De Fietsenfabriek” and needed to print a scale model. I was asked to print and help them during the process of making the 3D model of the bicycle and prepare this model for printing.

Quinten and his BoSteck Bicycle

During the process of creating the BoSteck Bicycle, the name of the concept bicycle, I helped Quinten and Twan Smeets, who was responsible for the CAD model, in translating the original design concept to a concept which was finetuned and ready for 3D printing (FDM).

After a few meetings consulting and giving feedback on the 3D model, Quinten and his team decided to print the scale model in different materials; ColorFabb Translucent Red, Shiny Silver, woodFill and bronzeFill. The scale model consisted of 46 individual parts and took around 30-40 hours to print.

A small selection of the parts using PLA, woodFill and bronzeFill

The print was a challenge, looking at the amount of parts and different materials. The bicycle was scaled down to 30% of its original size, therefore making it one of the largest projects that I took upon through 3D Hubs. The global measurements of the bicycle were around 400x200x75mm.

The finished scale model

Print Details

Printer: PrintrBot Metal Simple

Resolution: 200 micron (PLA, bronzeFill) & 250 micron (woodFill)

Temperature: 200c (PLA, woodFill), 210c (bronzeFill)

Heated Bed: yes

Surface adhesion: hairspray

Brim: yes, some smaller parts

Infill: 5-10% for most parts, 20% for smaller parts

Material: @ColorFabb Translucent Red PLA, Shiny Silver PLA, woodFill and bronzeFill 1.75mm

Slicing software: Simplify3D

Challenges

Due to the maximum printing dimensions of my PrintrBot Metal Simple, it would not be possible to print some components at once. Therefore a compromise was made by printing out a few components in parts and gluing them together during assembly. This project is a great example how to deal with making larger objects than the maximum printing dimensions of your 3D printer.

Halfway through the print my nozzle jammed due to the quick swap of different “special” filaments. I experienced more jams when using woodFill and bronzeFill based on their characteristics. While woodFill needs relatively more flow while printing (I printed woodFill on 110% flow) bronzeFill tends to be heavier and clogs up the nozzle more easily. Swapping the nozzle for another one quickly got me printing again.

In additional to clogs and nozzle jams, my “recipe” for woodFill is mainly turning off retraction. This adds a lot of stringing, but prevents any clogs or jams of the filament while printing. The strings are fairly easy to remove after the model is finished. Printing on a lower resolution also helps this problem. The woodFill parts for the scale model were printed on a resolution of 250 micron.

All in all this project was challenging in terms of the quantity of parts that needed to be printed. There were a few reruns required for parts there were giving problems or failed such as the small cilinders that connect the wheels with the frame and a few other parts due to the clogged nozzle.

That aside, the project was a nice collaboration with the local community and giving back advice and support on working with 3D printing services. It was both a win/win situation for Quinten and his team and me to gain more experience in working on larger prints and different types of filaments. The students did a great job in delivering the files (ready to print) and assembling the bicycle within a few days time.

If you are interested in some of the other projects or example prints that I have made in the past, check my hub located in Eindhoven.

Ken