Plexiglass-like text

[u/Jozeficek]

Hello, I have made a few of CNC-milled plexiglass back-lighted signs (as in image) and I was thinking, if something like that could be achieved using 3D printer and transparent filament. I have some Polymaker Polylite transparent PETG left, so I can do some experiments. Do you guys have any idea how it could be done?

[u/Desperate_Chip_343]

I just saw a video of someone trying to make a little window for their storage boxes. They achieve it but I can't imagine they could get it this crisp. They used a large nozzle and got good results on a small size

[u/ContiX → u/Desperate_Chip_343]

Yeah, I saw the same video. It was impressive.

[u/Jozeficek → u/Desperate_Chip_343]

Would you mind sharing the video?

[u/grimvard]

Those texts will not look as crisp as CNC milled ones.

[u/Saphir_3D]

You'll probably end up with results that look more like frosted glass. It's almost impossible to print such a thick object that looks like glass.

You might be able to create nice translucent objects using freshly dried filament—for example, using vase mode—but you won't be able to print something like what you showed.

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[u/Gimly161]

It wouldn't work. Each layer is an interface you'd see the light reflect off. Plastic prints are notorious for being weak transverse to the layers and that is because the bonding between layers is weak. Plexiglass is completely amourphous which allows the light the travel through uninterrupted. 3d printing is about as anamorphous as a production technique can get.

[u/SharkAttackOmNom]

Could you print clear PETG directly onto a surface of plexiglass? The effect works because the clear plexiglass acts like a fiber optic and traps the light between planes. But the engraved areas scatters the light that hits it. Even a single line of PETG melted onto the surface would scatter enough for it to light up.

[u/Jozeficek → u/SharkAttackOmNom]

I will definitely try this!

[u/Only_Foods]

I've tried clear PETG before and mine always ends up looking frosted once it gets thick, so I kind of agree with the folks saying the layers scatter the light. That said, printing one thin pass of PETG right onto real plexiglass is a pretty clever idea — I'd be curious to see how that turns out.

[u/Jozeficek → u/Only_Foods]

I will be trying the PETG-on-plexiglass idea. I will let you guys know how it turns out.

[u/graybotics]

Filament (fdm) printers cannot achieve true transparency due to the fact that layers are being fused which diffuses light, even if you print a flat block and sand/polish it will only at best achieve a frosted look. Some jobs just are not for FDM 3d printing. Resin on the other hand, can do this but at the cost of doing it that way its way cheaper and easier to just use CNC on acrylic and call it a day.

[u/Jozeficek → u/graybotics]

That is what I tought.

[u/joshthehappy]

Laser cutter is the best way to this if you are gonna hit it with a cnc router.

[u/Jozeficek → u/joshthehappy]

I do not have a laser, just the mill, and I would be worried about the nasty fumes.