Mario Kart Live Wheel Assembly

prusaprinters

While Nintendo has hit a very clever niche with their Mario Kart Live games and accompanying (required) Kart toy, there's one glaring problem which unfortunately shows up in real world use: the wheels, especially on the front, collect hair and eventually stop rolling correctly (or even at all) with no evident way of removing the axle for cleaning. One suggestion offered is to quickly wave fire under the problem area in the hopes that the hair will burn away before the plastic is damage, but I came up with a different solution.This set of models replaces the entire front wheel assembly. The same prints can be used on both sides without mirroring - just insert the axle piece from the other side. It requires no modification to the Kart beyond the removal of the factory pieces, and re-uses the factory tyres.Installation is fairly straight forward, but just in case:Sit the Knuckle on its side (as printed or upside down, depending on side) and install the Axle until it sits flush with the back - the taper and collar will help locate it.Locates this assembly on the Kart with the "tab" on the Knuckle pointed to the back and below the factory steering arm.Install the King-Pin from the top through both parts of the assembly. The wheel attempting to camber will hold this in place during use.Install the Tie Rod Pin from the top through the "tab" on the Knuckle - the flare will click into a slot and hold it in place.Install the tyre over the wheel Hub (it's easier now than later).Slide the wheel Hub over the Axle with the flat side pointed towards the Kart.Slide the Clip over the end of the Axle to hold the wheel Hub in place.NB The clip is less likely to come off on its own if the gap is pointed up or down, but a significant enough impact can still pop it (and the wheel) off.While this design naturally picks up less hair than the factory assembly, if it does you can simply pop off the clip, remove the wheel, and remove any hair before re-assembling. In the event any part is damaged a replacement can easily be fit without requiring large portions of the Kart to be dismantled.Removal of the existing wheel assembly is up to you. I may have designed this but I do not actually own a Kart, so all testing and disassembly was conducted by my younger brother. Only the wheel Hub requires supports, but it will require either "Everywhere" supports or Cura's experimental Conical Supports (not to be confused with Tree Supports) to print correctly. In the event you simply cannot get these supports to work (or just don't want to) I have provided a Split Hub which can be printed without supports but will not be as round which may or may not compromise balance. The tyre will hold it together in use.Two alternate variants of the wheel Hub have also been provided. The standard and Split Hubs have a 0.2mm clearance from the Axle, while the alternatives have 0.3mm and 0.4mm as indicated by their filenames. They are otherwise identical. There is no alternate Split Hub.No matter which Hub you use, ensure that the hole through the middle is clear of debris. This is especially true of PETG and other less viscous filaments.You need to ensure at least the Axle piece prints with as much layer adhesion as possible to prevent damage during collisions. This means potentially running a higher temperature than normal (up to ~245°c for PLA) or less/no cooling, and also means that ABS or ASA are not really suitable. You could try printing it on its side but I've never been able to get it round enough when doing so (a -0.2mm offset will remove the lower lip).I would recommend printing either the Hub or the Axle out of a low friction, low wear material. PETG works extremely well, POM/Delrin would be even better (though is significantly more expensive and awkward to print). It will still work without doing this, just not necessarily as well.Most of the pieces have a very small footprint, so you may need to use a Raft or Brim to aid bed adhesion.