Photomike,
Let me make it a little clearer. travelnutz only uses mirror clamps where they are the best to use and with stainless steel screws in the existing holes like on the entrance door plastic storm windows because they are outside and below flush with the door and being clear, you can hardly see them. Most to nearly all storms are held (clamped) in with screw thru plastic screen finger turn clamps or feet. The larger heavy storms are held on with appropriate sized stainless steel fender washers with a stainless steel screw into the existing OEM mounting /frame hole thus creating a clamping action. These storms are simply too heavy to be held on with the little plastic turn clamps because of the jerking and bouncing that occurs when driving. I always use the .220 Lexan etc except for the very small less than 8' X8' storms. Only need a few washer clamps with the .220 and the storm will be secure and stay flat. Need twice as many+ clamps with the .100 because it bows between the clamps and leaks air if too far apart. Way too flexible! Also looks wavy and not professional.
The only hole thru my plastic storms is the hole for the crankout window shaft for the lower window portion on sme windows. The hole for the crank serves as a bearing for the crank as it's about .010" (about 2-3 hair thicknesses) larger than the crank barrel. No pressure at all on the storm from the crankshaft barrel. I've never had a storm crack in any one of the storms I've made yet and over the many I've made in the last more than 20 years and 5 RV's. Using clamps, I can install or remove any storm is seconds.
Storing the storms we take off in summer is so easy. clean the windows and put a single sheet of newspaper between each and an old blanket draped over the vertical standing stack and put them against a wall in the back of a quiet seldom used closet in the house or in the basement or the garage. They'll still be there for nesxt year's installing and scratch free. You'll scratch them a lot more just cleaning them. Don't ever use any dry paper or a dry rag to clean them. It will scratch and swirl mark them. A damp old clean tee shirt works great and so does a clean terrycloth if not rubbed hard. Very soft papertowel with a little windex spray will work too.
Photomike, look closely at the pics I emailed you and enlarge them if you need more detail. if you need more to clearify just tell me. The pics are from several different RV windows. That's why you see some little differences. I wanted to give you several examples.
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