Simple embedded nuts for 3D prints - neater fastenings - and no special equipment required!

Screw fixings are a great way of holding your 3D printed parts together, and by embedding the nuts in the print, they needn’t spoil the look of your project.
Whilst threaded heat-set inserts are available, they can be tricky to work with - especially if you don’t have the right specialist equipment - and easy to get wrong, a wonky insert resulting in a ruined print.
The simple technique I share in this video is to insert a standard nut - mid way through the print - adding extra layers on top to hold it in place. A bit of extra set-up in your CAD software is required, but other than that the method is straightforward - either pausing the print for insertion, or even doing it on the fly.
The download for the test print can be found here: paterpracticus.com/downloads
Time codes:
0:00 Introduction
032 Prototype
0:50 The idea
1:07 Test printing
1:34 Nut insertion during pause
2:11 Proof of concept
2:23 Development
3:00 Adding to my project case CAD
3:14 Prepping files in Cura
3:36 Printing my project case
4:12 Inserting the nut on the fly
5:07 Assembling my project case
5:23 Advantages over heat-set inserts
5:48 Finished case
5:59 Link to downloadable files

[@KevinMullett]

Nice straightforward explanation. You came up in suggestions. Here's a well earned comment. 👍

[@paterpracticus]

Thank you.

[@locorocohui]

my man consider doing a pressure advance calibration on your printer. you have slight signs of it in your prints! nice vid

[@paterpracticus]

Not sure what that is, but I’ll definitely find out. Thanks for the tip.

[@buildtestbuild]

Cool project! FYI, most slicers can add "pause" gcode commands at specific layers. I've done it with prusa slicer and on a Creality CR10. I know the printer firmware has to support the command as well, and I don't know if the firmware on the Ender shown supports it or not, but you can change the firmware on an Ender if it comes to that. If you put the pause command in the slicer or even in the gcode file yourself, when the printer gets to that point it will pause without you having to watch it like a hawk. This makes it so much more convenient to embed magnets, nuts, or other things inside a print. Another thing you can do instead of the "pause" is to insert a color change (I believe that's M600) which is intended for you to swap the filament while the printer is paused. Of course there is no need to swap the filament and you could just embed your object and tell it to resume. I didn't hear you make mention of it, so I wanted to make you aware of it in case it helped you out in your project!

[@paterpracticus]

I had read up about that, but wasn’t sure if the Ender (being kinda basic) would be able to do it. Actually, the manual pause worked pretty well and with a 2 layer window, accuracy wasn’t a big deal.

[@SoloGamingZA]

@@paterpracticus Yes the Ender 3/3pro do support pause at layer height within Slicers, I have done it about 5 years ago when I used Cura (Always hated that slicer never had any good prints from day one on multiple printers. Prusa Slicer is a way better Slicer than Cura with better and more advanced features and print for print back to back prinyts between same model with same settings on Cura with no changes to the printer the ones on Prusa slicer always comes out better.) With the Prusa modifiers you can select areas in a print you want to print with different infill % and patterns and even different types of material like PLA and TPU and even print at different speeds at certain areas or even printing multiple objects on the plate each with its own infill and speed or nozzle temp settings and save it all in one GCODE. That is how I make phone cases out of PLA and TPU in one print in one gcode without needing to sit and time everything as the printer will let me know when the next step is available.

[@paterpracticus]

That is all really helpful. I must delve more deeply!

[@CuttinInIdaho]

you can also bury magnets and thin strips of steel and totally cover them. Making a case that has an inner lip, and magnets around the perimeter would make a clean, fastener-less design.

[@paterpracticus]

Great idea. But guessing they can’t be too deeply embedded in the print to stay working.

[@CuttinInIdaho]

@@paterpracticus exactly right

[@ket7926]

There is no point in using 100% infill ever (maybe if you really want the weight) To make the parts stronger you can do more perimeters and do 50% or less infill The weakest point will always be the layer lines adhesion. With 100% infill you're just extending the prunting time by a lot and wasting filament

[@paterpracticus]

In my case, the walls are only a few mm thick, so not much wasted with 100% infill. But, still experimenting on other jobs. 40% seems to be a sweet spot.