We clean the fibregass walls with a special fibreglass cleaner/polish, but for the windows, only water on a soft Microfibre cloth. So far it has worked well.
When BBQing outside the caravan, be careful to cook well away from the windows or you can get a fine greasy mist on them. Would be hard to clean off without Windex!
If I remember right use turps and not metho - metho will melt perspex. Try it on a spare piece of perspex before you try it on the windows. Or maybe one of the commercial glass cleaning products would do it fine...
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If there is such a thing as a tourist season.... why cant we shoot them?
When we were at the Goldstream factory in 2006 the lass who was detailing the caravans before they left the factory was wiping over the acrylic windows with "White Spirit".
We purchased some from Bunnings, next to the turps and metho in the paint section, and usually give the windows a wipe over, soft cloth, after washing the van with a good automotive wash and wax. The windows then seem to sparkle, so to speak.
A product that I have used on my boat windows and similar for years is called "PLEXUS", It is a essentially a plastic/acrylic polish. It cleans and polishes and leaves the exposed side with a "polish" finish. It comes in a spray can and if used sparingly will last for ages. Also great for cleaning the lens on your glasses.
Many years ago, in a previous life, I regularly used good 'ol Mr Sheen on aircraft windscreens and found it worked just as well as any of the fancy stuff available then.
If its polycarbonate, be careful useing anything that looks like turps or the other thiners type ??..can make the poly go white and it wont clean .. I did this to my boat windscreen.. Looked like I tried to clean it with tooth past...I had some over spray on the screen..Big mistake...
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Land Rover Discovery Chipped TD5 Manual ,Air Springs, Anti Sway. T.C. Auto level. Van, Roadstar 21.6 Voyager 4000 all sola powered.