I 3d printed a custom lid / back panel

I 3d printed this custom lid for my mnt reform 2.

This is my second attempt at this. This is not currently a good solution but just about good enough for me to leave it on and use it for a while, hopefully until my next revision.

I modified the .step file from the mnt repository using FreeCAD and made some optimizations for 3d printing. Some of them are based purely on guess work, others on earlier attempts at this. The most important change I made is making the screw holes big enough to take threaded inserts. This was actually suggested by @mntmn and it does wonders.

The metal back panel is optimized for weight, but with 3d printed plastic that isn’t much of an issue, so I made the panel thicker wherever possible.

This print has many issues. For one thing I printed at low quality and low infill. It is not intended to be the final version of this, I just wanted to see if everything would fit, which it did. Also I used a Creality Ender 5 Plus that I purchased specifically for this purpose and while the printer is large and cheap, it is also pretty crappy. I have already ordered a couple of upgrades for the next run.

The issues I have with this print include massive under extrusion to the point of de lamination of layers and one piece breaking off when I tightened the screw. Also the model is slightly too long (front to back) resulting in a bend when mounted. Not quite sure what caused that. Also this was my first time installing threaded inserts and I did it using a soldering iron with a regular tip, which was not well suited for the task. Finally with the low infill and the thing being made from plastic, it is not actually very sturdy. When I press on it from the back, it shows up on the LCD in the front :grimacing:

I used orange rather than black for debugging purposes. One side effect of that is that the backlight from the LCD shines through the back of the lid :smiley:

For my next revision I plan on adding space for Wifi antennas. I’ve had quite some problems with bad reception on the reform and since I’m printing plastic, I might as well take advantage of it. I’ll also want to remove more of the weight optimizations to make it more stable.

The end goal is to have a custom lid with my own logo of choice. But I am not sure as of yet how I’ll make the final model. I might attempt to print it at a higher resolution and with 100% infill, or I might get it made at shapeways. But that is a problem for future me, first I’ll do some more tinkering and print a couple more prototypes :wink:


Very cool! I love the enclosure myself so I wont be doing something similar, but I do like how making your own lid gives you all kinds of customization options! Thanks for sharing!

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This is really cool. I wonder if I could hide my 8db wifi antennas in something like that. I only know how to use OpenSCAD, so I’d have to re-model the lid in it, but… might be worth a try?


very nice :clap: … I dig the mixing of black with some touch of color … looking forward to the final version

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Love it! Very cool. This is the kind of post I’ve been waiting for!

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I have finally printed a new and improved version of the lid! It’s main feature is that it now has room for W-LAN antennas.

The last print was pretty good and I ended up using it for a while. But it was too flexible. When I pressed on the lid, it would bend inward and touch the panel. Eventually I got concerned and stopped using it.

To mitigate this, I enforced the model in several places by removing a bunch of empty space. I also printed with 100% infill and 0.1mm layer height this time around. Over all I am happy with the result. The print looks a lot better and is more sturdy.

Since the last print, I also made several changes to the 3D printer in the hope of improving print quality, although with limited success.

I also got a set of specialized soldering iron tips to help with inserting the brass thread inserts. This worked great.

Having the W-LAN antennas in the lid makes a huge difference. In a series of before / after measurements I found the reception improved by 7 to 10 decibel. If you’re interested, the antennas I used are the ones here.

Unfortunately I forgot to draw a channel for them from the left hinge which is why I ended up having to file one out of the print :sweat_smile:

The 3D model I used was modified from the the .step file in the upstream MNT repository using FreeCAD. You can find all the different versions in my Git repository here: Niklaus Hofer / mnt reform 2 laptop lid · GitLab

Modifying the .step file in FreeCAD is a bit like editing a PDF file in Libre Office - it works and the result looks OK, but the state in between is cumbersome and rather ugly.

Because of this I have now started re-drawing the model from scratch in FreeCAD, but these efforts are on-going.

Note that I have a beta model of the MNT Reform which has a different lid design. The from scratch re-draw will be of the production model. This should be better suited for 3D printing anyway since the cut-out for the panel is less deep, resulting in a more sturdy print. But I have yet to convince @mntmn to sell me a production bezzel to match the production lid… :wink: