Nelson Traveling Sprinkler Parts

thingiverse

We have a Nelson Traveling Sprinkler that got hung up and stripped the final drive gear, forcing us to look for alternatives. Since buying a full gear set from Nelson would cost $30, we decided to take matters into our own hands with calipers and a 3D printer at our disposal. Our solution was to reverse engineer the gear, of course! There are three versions of this gear uploaded online, with the "correct" gear being the .45 inch version. However, on my printer, all dimensions except for the center hole were printing correctly, so I made a .47 inch version since they consistently printed at .43 inches. This one slipped right onto the shaft without any issues. I've included a .46 inch version just in case. I've marked this as a work in progress since I'll be adding more gears as I'm able to model them. Edit 8-16-16: I was requested to model the shutoff platform that attaches to the hose, so I've uploaded it along with a ground stake. The hole included for a stake is designed to allow a hot nail to be melted into the platform, while the cross design should allow plastic to flow over the head of a nail to capture it in the part. Since the platform just barely fits on the build plate of my printer and I don't need one, I'm not going to print it. However, please post a make if you do make one, so I can see how it works. If it doesn't work as expected, I'll make changes accordingly. https://youtu.be/k6nKQTk2MIQ Edit 6-16-18: I added a replacement front wheel for ease of printing. Since the original has knobs that might not be necessary for tracking a hose, I've excluded them from this design. Print two and replace both pieces, even if one isn't broken. It's not designed to be a direct replacement. Print Settings: Printer: Flashforge Dreamer Rafts: No Supports: Yes Resolution: .3mm Infill: 50% Notes: I printed it in MakerGeeks Yellow PETG. Be sure your supports extend beyond the edge of the gear teeth. ABS should be strong enough, but normal PLA might be too brittle. A premium PLA would probably be better if that's all you can use. Edit 8-16-16: Since I installed this gear, the PETG has stripped out. I think it's a combination of the sprinkler getting hung up again and the PETG having a shear strength lower than the factory nylon gears. I've ordered some Taulman Alloy 910 to reprint the gear. Hopefully, the Alloy 910 will hold up a little better.