G'day D42
Further on the exhaust safety screens, as mentioned before, I use fine mesh off car air cleaner filter elements, or another source being some oil filter cartridges, but these need a good de-grease before use.
I also turn and bore thin brass discs to fit at each end of the screen which keeps them nice and tidy. You can either solder or glue the mesh to the discs, whichever suits you best.
Cut the mesh to the height you want, then roll it around a piece of rod of a smaller diameter than the finished diameter, and it will then clip onto the top and bottom discs. then you can trim any overlap and solder or glue the joints.
Ian