Texas Instruments Calculator Front Covers (TI-84 Plus, TI-84 Plus C, TI-90 Titanium, and similar)

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I needed a replacement cover for a TI-89 Titanium edition that I was selling on Facebook marketplace, so that the buyer would be satisfied. Luckily, I had another TI-84 calculator that still had its original cover so I could recreate one for my TI-89. All of the measurements in this post are my own, so they could be not exact to the original part, but the printed part still works splendidly. I am going to include them, a short explanation, and the model files so you can more easily modify/make your own. It would be cool to see a TI calculator cover that had a hinge so the front cover folded open rather than coming entirely off. The key measurements include: For the rail/slot cross section profile The distance from the calculator front keys to the to the far side of the cover slot. 12.7 mm (0.50 in) The size of the cover rail slot on the calculator. 2.0 mm (0.079 in) The depth of the cover rail slot on the calculator. 1.27 mm (0.05 in) The width of the calculator (from left to right). 84 mm (3.31 in) Rail start from bottom of the case ~40 mm and a rail length of 79 mm. For the case profile The distance from foot to head on the front of the calculator 187 mm (7.36 in) The curvature of the calculator side cross section Measured to be 10 mm (0.39 in). The curvature of the calculator foot front cross section. Assumed tangent to both edges, and measured a foot horizontal length of 34 mm (1.34 in). I created a rectangular profile with an offset from the calculator body of 0.2 mm, and designed a rail from the side of the rectangular profile with similar tolerances and a 60 degree angle so that it would not need supports. I went with a 2.2 mm shell thickness. I also created one with an angular side profile so all support are eliminated by not having the curved 10 mm surface. EDIT Later, I found a TI-84 model on GrabCad so I am linking it here. There is also a case on there I saw too, but I did not like it very much.