A lot harder than plexi... and more expensive (diamond tools - glas is really hard). But that is the reason why i chose glas... it looks a lot better than plexi (in my opinion), lets more light through, doesnt get scratched, its heavy and makes my
PC even more silent. I use my trusty dremel (the orignal not some Toya or sth).
That dragon took about 4-5 hours to etch. You need a really steady hand... it isnt easy to wield a whining dremel and etch such thin lines (thick are even harder cause the width must be the same everywhere!). Precision is the most impotrant thing. If you make a mistake, it will be visible after the LEDs are turned on and it can ruin your entire work.
There a lot of things taht you need to learn by yourself if you want to etch glass. An example... cooling the surface and diamont tip with water makes the diamond wheel piont live 100% longer (or more) but the water gets dirty really quick and after a few seconds you cant see the glass at all! The way that you hold the dremel is really important, holding it the wrong way will kill the diamond wheel point within 5-10 minutes!
So... yes etching glass is difficult but a little practice and a few killed diamond wheel points and you will learn it

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