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Megladon
10-29-2012, 01:09 PM
I`ve been noticing fine hair line scratches in my windows recently. Can they get marred just like your paint? I`ve been using IG tint safe with MF glass towels made by peak. Bought them at Pep Boys for a deal. They are soft, and figured I wouldn`t be using them on paint so went ahead. Am I doing something wrong. I already stress enough on keeping my paint swirl free as much as possible, to start worrying about glass.

Accumulator
10-29-2012, 01:53 PM
While today`s autoglass isn`t as hard as it used to be, it`s still generally pretty tough. I`d think the marring came from dirt/etc. rather than the MF itself. But then I`m assuming you cd-tested the MF...

togwt
10-29-2012, 04:36 PM
Moh’s scale of hardness; an adaptation of that hardness scale (1 - 10) Glass = 6



So how can a dense (hard) clear coat be so easily scratched?



It’s a matter of physics, not material density (material hardness). Force acts through a body that has a surface area; if the surface area is really small while maintaining an equal force, the pressure becomes astronomical and the object under pressure capable of penetrating the surface of an otherwise tough material.



Newton`s third law of motion [: when a first body exerts a force F1 on a second body, the second body simultaneously exerts a force F2 = −F1 on the first body. This means that F1 and F2 are equal in magnitude and opposite in direction]



That’s why a micro fine thread that is twice as fine as silk and a 100 times finer than a human hair, in an otherwise soft towel will scratch your paint. And the same reason a mosquito can penetrate a rhino hide with its proboscis (stinger).



If you press down on your paint finish with your palm it feels really hard and tough, but that’s because the surface area of your palm is relatively large and what you’re actually feeling is the resistance of the steel underneath the paint. Try pressing your thumb nail into the paint with the same amount of force you used with your palm, if you dare.

Ron Ketcham
10-29-2012, 07:21 PM
Jon, excellent!

Not sure that many will be able to comprehend and accept the science of reality.

For year`s, when teaching the Automotive International`s Prep Excellence Course, attempted to present the "science" regarding the "density" of coatings, as well as the "reactivity of surfactant based cleaners"," how heat expands/increases", the abilities of the cleaning solution and it`s components, when attempting to clean the normal materials used in an automotive interior.

A couple of times, even gave the students a new white T shirt and asked them to wash them using the same laundry detergent, but with the various heat of the water options and come back and share the difference in the "cleaning/white" of the shirt.

I can only hope that many will put away the "I saw the ad, I read the ad, my buddy told me, I etc, etc" and start to deal with the real world of chemistry of car care products.,

Grumpy

david2013
04-06-2013, 06:42 AM
"Don’t worry; you can remove scratches from glass. You just need to follow some steps such as:

1: use wood cleaner to buff plastic lenses.

2: buff the scratched plastic glasses with brass or silver polish and a soft rag.

3: use the cleaning spray.

4: dab a non abrasive. toothpaste on the glass.

5: make a paste of baking soda and water.

6: wax your glass with vehicle wax.

7: try a glass etching abrasive designed for glass art project."

togwt
04-06-2013, 08:44 AM
TOGWT Autopia Detailing Wiki - “Polishing Glass” - http://www.autopia.org/forum/guide-detailing/137878-polishing-glass.html#post1464140

Alfisti
04-06-2013, 11:22 AM
"Don’t worry; you can remove scratches from glass. You just need to follow some steps such as:

1: use wood cleaner to buff plastic lenses.

2: buff the scratched plastic glasses with brass or silver polish and a soft rag.

3: use the cleaning spray.

4: dab a non abrasive. toothpaste on the glass.

5: make a paste of baking soda and water.

6: wax your glass with vehicle wax.

7: try a glass etching abrasive designed for glass art project."

What?? Plastic glasses? :nixweiss