Our dishwasher is getting to be a certain age. And the plastic parts are showing it. Especially after one of the youth tripped over a cat and onto the bottom rack. When the wheels fall off they have a really unpleasant tendency to lodge against the heating element and melt/char. It stinks up the whole interior.
So I fired up Openscad and my cheap plastic vernier calipers. First, a peg to hold the remaining wheels in place after the old pegs failed. I am kinda proud of the divot that lets the peg bend inwards, because it’s straightforward openscad code (possibly even amenable to turning into a module) rather than something with polygons (I hate polygons). Less proud of the overhang at the top of the peg, which would have been steeper. But with the cheap plastic calipers I wasn’t really sure of my measurement.
For the wheel, I just combined measurements of the existing wheel with the peg design, and presto! The result is a one-piece part that probably would have been hard for the manufacturer to injection-mold cheaply. Speaking of cheaply, the cost estimator on my octoprint installation figured the price of 4 pegs — made out of recycled PETG from the late, semi-lamented Makergeeks — as something like 48 cents. Even factoring in the 20 minutes of design time, I think I may have beaten the $36.98 for an OEM replacement (you can only buy the whole carriage) online.
(And if your dishwasher is suffering similarly, you can check the files at Youmagine.)