Nova Mod - An i3 MK3S(+) Upgrade

I implemented all these mods over a few days after deciding to gift my MK3S+ to my father for Christmas. Unlike my other designs, these modifications are one-offs rather than the product of a lengthy, iterative design and testing process. I did my best to tidy up the design files, though they’re still far from perfect. Also, the name “Nova Mod” might imply a larger overhaul than it actually is—it's really just a light bar, black fasteners, reprinted Z motor mounts and Z top pieces, a tray, and an LCD cover.

Baseline

Apart from the x-axis-ends I reprinted all original parts in Prusament Matte Black PETG. That's the colour theme of the current MK4 design, which looks fresher than the original all orange MK3. 

LCD Cover

This was a tough one - a multi-colour, multi-nozzle print, made possible by the E3D Revo on my Prusa MINI+ and butchered together from multiple individual slicer exports. I can't really provide files or instructions for this, only the message that it is possible if you really want to do it. The font used on the original PRUSA parts seems to be Neue Helvetica Pro 75 and 95 Bold. It's a commercial font, so you have to find an alternative or get creative. I started by removing the embossing on the original part and then adding my own custom text in Blender using Boolean modifiers. You can find the cleaned version of the lcd-cover in the download section. A better alternative to this may already be available on Printables, e.g. this SCAD based version by ntdesign.

Printing Procedure I started with a 0.25mm nozzle on the text bits, changing filament colour from light to dark: Signal White, Urban Grey, Prusa Orange. I then switch to a 0.4mm nozzle and Matte Black filament, to complete the first layer as well as the black parts on the second layer. For the text I switched to Signal White again to get a uniform backing on all letters. After that switch to Black again and continued with the rest of the print. 

LCD side-mount

When it's not strictly necessary to access the printer from the front, a side mounted LCD reduces the footprint of the machine by a lot.  It makes it appear more compact and gave the opportunity to balance the visual appearance by adding the tray to the other side.

One problem with this mod is that you can't access the SD card slot anymore, which is not a big deal in my case because I'm using Prusa Link anyway. As an escape hatch I went with a design that clips into the 3030 extrusion. With this approach you can simply detach the controller to access the SD card slot if necessary.

Light Bar

First of all: LED lights connected to the printer power supply will flicker! More on this further down below. Sadly I couldn't just go with the popular LED Light Bar by In3DSpace. The Aluminium profiles that are used in their design, weren't available in Germany. This is the only part in this collection that went through multiple design iterations. In my first attempt I copied the shape from the original design and used a smaller cross section to fit my LED profiles. 

What I like the most about this mod is not even the excellent lighting you get from 72 bright 4000K LEDs but the change to the perceived dimensions of the printer.  

The flickering It's a bad idea to connect LED lighting to the same power supply that you are using on a PWM modulated hot end and heated bed! They are flickering and you can't just put a capacitor on the line to smooth it out because the amount of energy required to even out the voltage drops is much bigger than you'd think. To really get the most of this use a separate power supply. 

I designed a custom PSU case that I had planned to mount in the rear part of the printer. Fortunately PRUSA is serious about user safety and kept all mains voltage inside of the original PSU.  I only found out about about  that after designing the custom case. I did not feel like drilling into the PSU to get power lines connected to the main switch, so I went with the flickering and added a switch. An easy alternative would be to use an external plug-in power supply and connect it with a barrel jack connector. 

Side Tray

To balance the side-mounted LCD I came up with a design for a tray that broadly resembled the shape of the control unit. It's a simple to level side tray that fits a standard printer utility tool set: 6, 7 and 17mm (cut in half) wrenches for changing nozzles, nozzles, hex key,  needle, Filament Cutter by Pomi, tweezers, Hex Scraper by visle.

When assembling, put the clips into the 3030 extrusions and then slide on the tray.

Reverse Bowden

I implemented this but decided to ditch my efforts because it won't work well with the LED bars. You can still find the STL files in the download section.