Pentel Graph Gear 1000 Inner Barrel Replacement

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This model serves as a replacement for the Pentel Graph Gear 1000 mechanical pencil's inner plastic barrel, which tends to break frequently. I printed this on my Ender 5 using PLA and found it to be satisfactory. However, there are some notes to consider. The threads on this model are quite small and not precisely accurate; the smaller one measures 7.08mm in outer diameter, while the larger one is 7.75mm. Due to their tiny size, I was unable to measure the pitch diameter of these threads. Through trial and error, I discovered that the pitch appears to be approximately 0.5mm. For the sake of simplicity, I assumed a 60-degree angle for the threads. Unfortunately, the start and stop of the threads were not modeled with precision. It's worth noting that the inner diameter where the metal lead holder tip slides in and out can sometimes be too tight on certain printers. In such cases, using a file or possibly a drill bit that is slightly larger than the ID can help to widen it, allowing for smoother movement of the tip.