Australian Tube Products (ATP) Stem Cap

thingiverse

Australian Tube Products (ATP) created handlebars and stems for bicycles, one product being the 'Ray Gun' stem made from steel tubes brazed together with a plastic cap that fit snugly into the rear of the stem. This innovative design prevented users from getting injured by protecting them from water and contaminants seeping in through the stem. Over the past 60 years, however, the plastic caps were either lost or degraded due to exposure to UV light. Print Settings Printer: CTC Rafts: Doesn't Matter Supports: Yes Resolution: 0.2mm Infill: 20% Notes: I chose ABS as the preferred material because of its resistance to sun exposure. I printed at a 0.2mm layer height for a balance between print speed and detail, knowing that 3 shells with a 0.4mm nozzle would be sufficient. Post-Printing The stem cap insertion is set at 20mm, while the internal diameter of the stem measures 19mm. The oversized stem cap allows users to sand it down to fit individual stems perfectly. Sanding and buffing or acetone smoothing will produce a finish similar to the original stem cap. How I Designed This I drew up this component in Solidworks using measurements and a reference image with a vector path of the original bar plug. The Solidworks part file has been included for anyone who wants to make adjustments.