I modeled the Shimano Saint M815 crank protector because I had an old rubber protector but it was universal so the fit wasn't the best it already was old so it wasn't good enough, so I copied the crank shape and modeled this crank protector, and it fits nicely, maybe try to scale it up or down a bit if doesn't fit (depends of printer tolerances…). I printed it from TPE so it's flexible but still rigid and protective enough.