Some good questions today:
1. How do you get dog slobber off the windows of your car? Dip a wet sponge into some soda ash (washing soda, or sodium carbonate) and rub it on as you would a powder cleanser. Rinse and wipe away. If there are white streaks when it dries, they can be wiped away with a bit of vinegar on a sponge.
2. Bore stains. Bore stains are ferric oxide (rust) caused by the oxidation of iron in the bore water by atmospheric oxygen. The solution for removal is an acid. And the best option is probably sulphamic acid, which you find in Easy Off BAM bathroom cleaner. Spray it on, let it soak for a minute or two, and it should just wipe off. Failing that, you could try powdered pool acid from Bunnings, or powdered citric acid (but I’m not sure where you can get that from).
3. Demisting your windscreen. I suggested a preventative approach – wiping the inside of your windscreen with dishwashing detergent. But off air, a truckie called in and suggested hairspray. That’s what I love about my radio show, clever ideas from listeners. As it happens, if you do have a misty windscreen, hairspray would be an excellent way to demist it (with one caveat).
The reason it would work, is that hairspray is alcohol based. We have seen that short chain alcohols possess the property to both mixed with oil and water to a degree. In this case, the alcohol will break the surface tension of the little beads of water that are scattering the light as it passes through your windscreen, making it look opaque (misty).
Because the alcohol breaks the surface tension, it allows the drop to wet, or smear, across the surface so that it will not disrupt the passage of light, and therefore the mist disappears.
The only problem with hairspray, however, is that it does not contain just alcohol – it also contains the resins that stick your hair together. And I’d suggest that spraying sticky stuff on the inside of your windscreen is not a particularly good idea, as it will suck up dust and cause the light to scatter badly, particularly if you are driving into the sun.
So the best thing is just to spray alcohol by itself. In other words, use Glen 20. Glen 20 is just an alcohol spray – that’s all it is. So you could spray as much of that onto your windscreen as you want and it would do a really nice job of demisting in a jiffy.
Tomorrow: Aluminium and Alzheimers