Laser cutter dangers

OK. This bloody laser is trying to kill me.

Shortly after getting it I checked it over. It needs some water flowing through it to keep the glass laser tube cool and the tubing was kinked. So I decide to blow through it to ensure the thin flexible rubber tubing wasn’t blocked and the coolant would flow OK. I assume the tubes would be empty so I wasn’t expecting to blast a load of stagnant water out of the tube all over me. Yuck. Oh well. It seemed to work OK so I filled it up with clean water and some antifreeze and continued to test it out. I was pleased to find the tube and PSU in working order.

A week later I was struck down with a really dodgy stomach bug. My wife (a GP) checked me over for the usual things but the tests came up negative. I mentioned the stagnant Chinese pond water and she tested for a few more things you wouldn’t normally check for unless you’d been abroad. Bingo! It turns out my bloody laser had given me a nasty water-borne amoeba like gut parasite called giardia. Easily treated once I knew what it was but I felt shocking for a week.

Later on I was looking to fit a new Z table and wanted to measure how close the beam got to a bracket. I know! I’ll hold a piece of wood in place and quickly zap the laser to see where the burn mark is. What I forgot was the the beam doesn’t magically come out of the lens. It comes in from the left and bounces off a mirror. At least it would do if my hand wasn’t in the way. A few milliseconds of an unfocused beam was enough to make me think I’d got an electric shock. Until I smelt the burning flesh. Nothing too bad, but if that beam had been focused down to a point 0.1mm across it would be a different story.