A prefabricated model of a bottle cutter. To assemble, you will need 4 M4 bolts with a length of 15 mm, a 25x2 mm metal disc (I use a five-ruble coin) and two sections of a stationery knife blade. The standard model is designed for a 9 mm thick tape, to adjust the height, you can print several 'plate' models and a model with a place for the blade, or assemble your model, for example, in Tinkercad with the desired height.