I often catch myself watching a 3D print for several minutes just because the process itself is so interesting. I like taking a closer look at things, so after seeing “chilicoke’s” nozzle camera, that he made for his Voron printer, I had to make one for myself.

My setup is not yet finished but I’d still like to give a bit of insight to give me feedback or to get you started to build your own. Keep in mind, that these small cameras are quite fragile and fiddly, so be prepared to break one or the other. I’d also recommend using a USB-Hub for plugging in the camera because if you soldered a short-circuit, you’ll probably only fry the hub and not the USB port on your PC.

Camera

Finding a suitable camera was the first challenge. Since we really want to get a close shot of the nozzle, I had to find something with a short focus distance but still requiring little space. I first took apart an old USB microscope but noticed that it’s not suitable for this application due to the sensor on a big PCB and a separate lense.

Next, I bought a couple of USB endoscopes I thought might be suitable for the application. Unfortunately, most of them have a focus distance between 5 to 10cm which makes them in that state basically unusable for the application. Nowadays, most of them also feature a semi-flex cable which is really stiff.

USB endoscopes on Amazon (affiliate link) : https://geni.us/BswFX

I ended up choosing a cheap 17€ one from Amazon and thought I just opened it up to see if it’s usable. Opening the housing seemed difficult in the beginning. I ended up using my lathe to cut off the back of the metal housing after which the camera simply slit out. You don’t need a lathe for that, a metal saw or a Dremel should do the job as well.

I snipped-off the old cable and simply soldered a new, flexible USB cable on. Simply don’t connect the two wires for the integrated lighting and the remote switch. Only black, red, green and white are necessary. When buying a new USB cable, rather go with a cheap one because you want thin wires for flexibility. My premium one had really thick gauge wires that were a pain to route.

Focusing

The initial focus position of the endoscopes is usually too far away to get a nice, and crisp image. Chilicoke uses a plastic lense for that though I simply re-focused the endoscope. The sensor consists out of a sensor housing and a screwed in lense that is usually locked by some glue. I held the housing in a vice, slightly heated up the assembly, and was then able to rotate and therefore re-focus the camera. A line-marking helps to check your progress.

Lighting

I didn’t use the included tiny ring light of the camera and opted for bigger LEDs all around the hotend. I salvaged some white LEDs from a light strip to which I simply soldered wires. For my current setup, I connected all 4 of them in series and power them using 24V from the hotend fan line using a 470 ohms resistor to limit the current to ~30 mA.

I tried to space the LED as evenly as possible and at quite a low angle to illuminate the nozzle and not only the heater block.

Mount

I mounted the camera on the part cooling fan shroud of my Hemera extruder. The current design is more than quick and dirty but so far seems to work. The camera is covered in foam held in place by 2 zip-ties.

The challenge is to not melt away the camera, so I currently activate the part cooling fan, as soon as the heater turns on so that the cold stream of air constantly cools the camera. I also added a silicone sock to reduce heat radiation. So far, the camera has been working for a good 2h of printing.

Challenges

I’m not yet totally happy with the setup. For once, it’s a bit too close and I need to see if I can re-arrange the parts a little to get at least a bit away from the heater block. That would also reduce the risk of melting the camera.

Then there is the camera itself. It’s advertised as an HD 1080p camera. Even though it can take pictures in Full HD, I was only able to get a 640x480 video stream from it, which doesn’t look too great. I think I need to order some more cameras to find one, that might be even better suitable.

I also need to find out how to set up the camera better because it currently changes the exposure of the shot all of the time, the scene is different which is really annoying to watch. I need to find a way how to adjust exposure, white balance etc. manually.