

I was told that the trick is to not have the egg in its shell.
Take a cup, fill it one third with water, then crack your egg in the cup. Now it can’t build up pressure, it can’t explode.
It microwaved without exploding. As I took it out of the microwave, it exploded. It went everywhere. The floor, the ceiling, every cabinet door. I count myself lucky that I didn’t get boiling hot egg in my eyes.
Also, the noise attracted attention from everybody in the house, no way to just discretely clean it up before anyone noticed my stupid experiment.
Your magnet isn’t strong enough, or maybe there’s a problem with the surface of the scraper bit. Different thickness of glass requires different strength of magnets.
Mine is too strong, I wrap the handle in cloth to increase the distance.
My scraper takes algae very easily, but mineral deposits seems to require a blade.