Replacement cap for Park Tools DP-2 dummy pedal

prusaprinters

<p><strong>Update - 20 Sep 2019:</strong> I uploaded a v3 version with<em>even longer</em> threads with a nice taper for when your hamfisted coworkers in the shop keep stripping out the v2 version with the shorter threads. ಠ_ಠ Unfortunately I can't upload a version to make coworkers less hamfisted.</p> <p><strong>Update - 10 Nov 2018:</strong> I uploaded a v2 version with longer threads for when your hamfisted coworkers in the shop keep stripping out the original version with the shorter threads. ಠ_ಠ</p> <p><a href="http://www.parktool.com">Park Tool's</a> <a href="https://www.parktool.com/product/threaded-dummy-pedal-dp-2">DP-2 dummy pedal tool</a> is a simple tool that threads into the 9/16-20 threads on a bicycle crank so you can turn the drivetrain when a bike doesn't have pedals installed. The head is plastic, and a hamfisted mechanic<em>(which wasn't me, honest)</em> can easily strip the threads, especially since there's only a couple threads. (This makes it easier/quicker to attach the tool, you don't have to thread it all the way into the cranks)</p> <p>If the cap gets stripped out, the tool becomes worthless. According to the <a href="https://www.parktool.com/assets/doc/product/DP-2_instructions.pdf">tool's instructions PDF</a> it looks like you can order part #898 as a replacement, but since it's such a simple part, you could just print up as many replacements as you need.</p> <p>This thing is just that replacement, modeled to directly replace the #898 head of the DP-2. The threads are 5/16"-18tpi (not sure why Park uses SAE threads here as bikes are predominantly metric) and the nylock nut is 1/2", but a 13mm cone wrench works well. Hold the nylock nut with a cone wrench, and the cap will thread off, although you may find it easier to hold the cap in a vise or with channel-lock pliers as it fits pretty tightly.</p> <p>The original part has a cutout in the back into which the nylock nut fits, but I don't see much in the way of functional improvement in that. Removing the cutout makes it easier to access the nylock nut with a conventional open-end wrench, and allows the thing to be printed without supports.</p> <p>I also have a complete redesign of the PD-2 which is optimized for printing on FDM printers here: <a href="https://www.thingiverse.com/thing:3810500">Dummy pedal for bicycle maintenance - redesign for FDM printers</a></p> <h3>Print instructions</h3><h3>Category: Hand Tools Summary</h3> <p><strong>Update - 20 Sep 2019:</strong> I uploaded a v3 version with<em>even longer</em> threads with a nice taper for when your hamfisted coworkers in the shop keep stripping out the v2 version with the shorter threads. ಠ_ಠ Unfortunately I can't upload a version to make coworkers less hamfisted.</p> <p><strong>Update - 10 Nov 2018:</strong> I uploaded a v2 version with longer threads for when your hamfisted coworkers in the shop keep stripping out the original version with the shorter threads. ಠ_ಠ</p> <p><a href="http://www.parktool.com">Park Tool's</a> <a href="https://www.parktool.com/product/threaded-dummy-pedal-dp-2">DP-2 dummy pedal tool</a> is a simple tool that threads into the 9/16-20 threads on a bicycle crank so you can turn the drivetrain when a bike doesn't have pedals installed. The head is plastic, and a hamfisted mechanic<em>(which wasn't me, honest)</em> can easily strip the threads, especially since there's only a couple threads. (This makes it easier/quicker to attach the tool, you don't have to thread it all the way into the cranks)</p> <p>If the cap gets stripped out, the tool becomes worthless. According to the <a href="https://www.parktool.com/assets/doc/product/DP-2_instructions.pdf">tool's instructions PDF</a> it looks like you can order part #898 as a replacement, but since it's such a simple part, you could just print up as many replacements as you need.</p> <p>This thing is just that replacement, modeled to directly replace the #898 head of the DP-2. The threads are 5/16"-18tpi (not sure why Park uses SAE threads here as bikes are predominantly metric) and the nylock nut is 1/2", but a 13mm cone wrench works well. Hold the nylock nut with a cone wrench, and the cap will thread off, although you may find it easier to hold the cap in a vise or with channel-lock pliers as it fits pretty tightly.</p> <p>The original part has a cutout in the back into which the nylock nut fits, but I don't see much in the way of functional improvement in that. Removing the cutout makes it easier to access the nylock nut with a conventional open-end wrench, and allows the thing to be printed without supports.</p> <p>I also have a complete redesign of the PD-2 which is optimized for printing on FDM printers here: <a href="https://www.thingiverse.com/thing:3810500">Dummy pedal for bicycle maintenance - redesign for FDM printers</a></p> <h3> Print Settings</h3> <p><strong>Printer Brand:</strong> Prusa</p> <p><strong>Printer:</strong> i3 MK3</p> <p><strong>Rafts:</strong> No</p> <p><strong>Supports:</strong> No</p> <p><strong>Resolution:</strong> 0.100 mm</p> <p><strong>Infill:</strong> 20%</p> <p><strong>Filament:</strong> Hatchbox PLA black<br/> <strong>Notes:</strong></p> <p>Printed in PLA with great results. You could use ABS or PETG if you were going to leave this in a hot car, but that's about the only reason you'd need to use a stronger filament.</p> <p>I used a 0.100mm layer height to get better results with the printed threads, although 0.200 would probably work as well. The part prints pretty quickly even at the 0.100 layer height, so I don't think using the thicker layer height would be necessary unless you're in a rush.</p>