Be careful about doing that. Cutting lasers can be extremely dangerous in ways that are hard to predict. There's a reason commercial laser cutters are totally enclosed with safety interlocks that turn the beam off when a hatch is opened. If it happens to shine on anything reflective, it can send a beam right into your eye, if it's not fully enclosed. So the enclosure is a must. Here's some advice on the subject from Hackaday: https://hackaday.com/2016/06/29/tami...-laser-cutter/