The welder´s goggles should be dark ones for arc welding. The glas for welding with a torch is usually not dark enough. I selected the cardboard sextant as the bubble horizon was essential for me and I didn´t find a plastic sextant that could be easily fitted with it. We don´t have an unobstructed view to the horizon were I live.
Looking cool when you make an observation makes some bystanders think you can achieve GPS-like precision. It´s essential to do the math when nobody is watching if you want to keep up the myth.
Using the sextant at least tought me some respect for the ancient navigators.