There's nobody making open inkjet heads either.

Look, there's very few processes available to us in the non-professional scope. The devices that fabricate these printheads and LED rays are ultra-high precision themselves. It's giants standing on the backs of giants.

Yes, laser printers existed in the 70s. And an HP laser jet 2 would be about the best engine to try to replicate I expect. It had relatively few parts and they were all big enough that we could work on it by hand.

The software part we can do, rasterizing the data is straightforward and the tech has been there for years. We can turn a laser on and off with such precision that we could completely replicate how the commercial units do it.

Power supply, easy peasy. Chroma wire, no big deal. We're going to electrostatic this shit out of that transfer roller.

Where are you going to get the materials to scratch make a transfer roller that can handle 300/dpi? It needs to be utterly perfect. It needs to be absolutely exact so in the light hits it, it knocks off the electric charge. You're going to need a plastics lab in a clean room.

Let's put a pass on that and let's assume we're going to use a toner cartridge with a built-in transfer roller manufactured for some printer that exists and they'll keep making toner for it for some number of years.

Let's talk about diy manufacturing the scanning mirror. A 3D print's not gonna cut that. You need perfect segmented mirrors, beveled on the back to allow them to touch point to point. The positioning on them is going to be sub micrometer resolution. Even with the best 3D printing we have right now, you're going to end up with a wobbly mess.

So, we're going to move into a servo mirror. We put a fairly high-quality mirror between two servos and use them to make it go up and down. Teck here, it's doable. Until you realize you're going to need to have 300dpi. Now you need something capable of doing 2,500 steps over a few degrees of arc. You can't get closer to the paper to fix it because you'll end up with focusing problems.

Okay, so using a laser is probably a lost cause, but we're not out of tech yet. We just need a really bright, fast, focused light source. Let's move over to LED.

They put 2,500 LEDs and they strip 8 inches wide.

You're not even going to find a pick and place service that can put 300 LEDs per linear inch.

DIY is getting better in leaps and bounds with 3D printing, software, and medium to small sized PCB manufacturing.

But we aren't getting any closer anytime soon for true microprocesses. We're not going to be making amoled screens, LCD screens, we're probably not going to be making true processors. There's just a lot of manufacturing techniques we need that aren't going to happen outside of a lab or a clean room.