@EchoNeko15 I am the developer of T2Laser software which is not connected with Eleks.
I purchased one of their machines several years ago and found the supplied software to be lacking (and that's being kind) so wrote my own. I have since purchased several machines from Eleks and other vendors. Mechanically I believe the Eleks to be one of the best designs but the supplied controller and software are sub standard. Both are easily upgraded though, so I still feel like the Eleks is the best option for the price.
The perforated grid is made of aluminium 1.5mm. The support frame underneath is milled from a multiplex plate. Underneath is a 20cm air space, where the focus of the laser beam increases so that it does not burn the base plate. Additionally there is a piece of aluminium on the base plate. At the back wall there is a toilet ventilator which sucks the combustion gases and pushes them to the back via an air hose. Possibly a few air baffles in the lower air chamber would be worthwhile so that the extracted air is sucked in more homogeneously.
I has also 3D printed new ones for my A3 Pro. they work fine.
May I make an observation on your photo, the drive wheel is slightly out of alignment and as you can see is pulling to the outside if you re a line the drive wheel it might run a bit better. Not a criticism just and observation.
@Zax unfortunately I can't find (easily) clear acrylic with brown support, only transparent one. In the meanwhile I tried with the method you talk about, seen on benboxlaser.us: it seems to work, but with full power and vector feed rate at 200 I have the paper burned, colouring with black (impossible to clean, the ash is melted with the acrylic), and a lot of spots with paper melted with the acrylic. Per se, the image is correct (with a number of smudges, due to the temperature).
Maybe lowering the power, and/or speed up vector feed rate, using a ticker paper, and having a vented base, help to avoid such problems...
btw, do you use that acrylic with the brown paper backing toward laser, or in the back, mirroring the image?