CoreXY Laser engraver

Update
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Check out my update/remix that adds a Z axis and further improvements to this engraver!
https://www.thingiverse.com/thing:3123030

Introduction
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Some time ago I built a small DVD-Laser engraver but it wasn't really usable. Now this new one became reality by chance. When I upgraded my 3D printer Prusa i3 MK2 to the newer MK2S version I had a few spare parts, namely linear rods and bearings. Additionally, a 1 W blue laser from eBay was lying around unused... this is the result. ;-)

Disclaimer
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This is the obligatory warning. Lasers with such high powers are dangerous and can burn or blind you, even from reflections. Don't attempt to build this if you are not familiar with high power lasers.
Good quality laser protection goggles are a must! Don't use cheap ones. And always wear them! Beware that the laser might turn on unexpectedly when the Arduino is booting (it shouldn't, but don't rely on it).

Design specs
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