proof that using low powered diamond disc and coolant, you can cut and file toughened glass

i needed to take of many millimetres cutting and filing to avoid £150 remanufacturing charge!

my supplier and his factory production manager said it was impossible without it shattering as designed to.

i searched the net and youtube, all i found was shattering failures and non toughened glass successes.

i noted the 500w power tools worked initially but even cooled after a few mins shattered, got me thinking that the low power lighter tool might work, maybe a simple diamond file or carburundum sharpening stone??

well my first try succeeded, took 15mins to file off 30cm 2mm (4mm thick) or cut a slit that long instead.

theory: toughened glass is stronger because as the hot glass cools it absorbs energy molecular tightening? so if you approach that same 300c tempering heat anywhere it triggers an avalanche shattering every piece.

to avoid it, ensure you keep it cool, unstressed and only apply minimal power at higher frequency than its resonant frequency (ting it with your finger to hear that " frequency ", you should avoid applying anything making similar noise, so slower hand filing or higher frequency dremmel i figured)

if your glass gets hot enough to boil spray coolant its about to explode, or already did so be warned

possibly coolant spray beats being underwater or very wet, if immersion is propagating sonic waves worse ??

not for kids, obviously.

in spite of the scary "crack crack" noise you heard rattled me when i cooled it in the video (guess i should have cooled earlier) it did not shatter and its "ding" note (resonant frequency) was unchanged, so its now installed in my window over the double glazing as a removable privacy glass, i promise( jun 22' ) i will edit or remove this video if it ever becomes dangerous.