Allit EuroPlus Flex assortment box label holders (#P45)
Once a more a simple 3D printing part. Today, that’ll go into one of the excellent yet affordable (10€-ish, depending on the size of the swappable containers) “EuroPlus Flex” assortment box made by Allit. One of those (yup, stolen right from the manufacturer):
Outer size of that specific product is fixed at 370mm x 295mm x 55mm, and the inside is, aside from the front part that integrates the handle, fully configurable. There are 1×1 boxes in red, 2×1 in yellow and 2×2 in blue. For really large items that still need to be inside a container, there are also 3×2 green and 4×2 gray ones (not shown here), but I tend to just stick them in there without a container. I think I got 21 of them in use at the moment, from tiny M1.6 screws to PCB storage that uses the entire width of one box.
Marking the small compartments wasn’t that critical for me personally, but I recently introduced these at work. And when storing parts that look similar or even look identical because some idiot companies do not label their 0603 0.1% E192 speciality resistors for whatever reason, some kind of compartment marking is necessary.
Just putting on a sticky label from a Brother label printer doesn’t cut the mustard. I want them to be readable from above, even with the transparent lid closed, and regardless of the amount of parts that are inside. So I needed something to put inside the box that carries a label.
First thing that came to mind was some tripod kinda thing:
Well, that works, but it’s a bit fiddly. The one large piece that reaches the bottom of all compartments does make its way, but it steals some space. The flat top part that carries the label is so large that is basically needs to be removed first when removing items. And while it does self-center when printed to the correct size, moving the entire assortment box around with the lid (slightly) open can cause them to move upwards, so the all need to be seated again before closing the thing. It does print nicely though, as the top part can be laid flat onto the printing bed, and then the stem just grows to the desired size. With two walls it’s super sturdy, but at a desired layer time of a couple of seconds, it actually takes a while since that totally limits vertical print progress.
Again, yeah, does the job, but it’s not great.
But a colleague had a great idea – why not make a serif-L or U-shape?
And I tried and tweaked, and I think that is brilliant.
Here’s how it works: The overall shape covers the entire bottom of the compartment and one side (doesn’t have to, but it’s much easier to print). It then bends over another time and offers space for a 9mm label. That’s the easy two-minute CAD result.
Two additional 90° bends with very short overhangs offer a preferred orientation for the material when cooling. Without them, the edges bend to one side by chance, and additional layers usually follow suit, which leads to ugly, saggy edges.
Then there is a connecting line for the first layer, which offers additional surface area. Without that one, a good percentage of my prints fell right off during print, since their contact area is basically a string of 2x 50mm plus the 10mm for the label, times the extrusion width (0.6mm in my case). The print however is 49mm tall, so at 0.6mm width, the aspect ratio is 1:82 which (even with the angled sides) is a terrible idea.
There’s also the angle of the walls, which isn’t 90°, but actually a tad above. While that is not important for the print, it does make the part slightly oversized for the compartment, but since it is flexible at just one nozzle width, the print will fit snugly inside the box. Otherwise, it would be rattling around due to printing inconsistencies.
And, but this is dependent on the slicer: With the “Alternate wall direction” option in Cura, the printer doesn’t go around in a circular fashion with one retraction per layer. Instead, it just stops at the tiny overhangs, moves up in Z direction, and extrudes the next layer from here. When set up properly, there is not one single retraction needed for the entire part.
Prints do need minimal post-processing: Grab a pair of precision sidecutters and remove the additional line that fuses both ends. For very recent Allit boxes, it might be necessary to not cut them flush, but at a 45° angle on the large side with like a millimeter of material removed. It fits my boxes perfectly well, but the ones we ordered at work are apparently ever so slightly smaller (they now have a production date stamped in, so they likely have changed the injection mould).
On my Ender 5, a print takes 1.21m of material and 7:11min to complete, including homing, bed levelling and a quick nozzle wipe. So that’s probably 3 cents in material cost plus another one for electricity (due to the large bed, YMMV)
Fully assembled boxes look like this:
And of course with the lid open:
My label holders are not glued to their compartment, but they very well could be.
(+) One could grab the entire compartment by the label and remove it that way from the assortment box. N
(-) Lifting the contents of the compartment by the label holder sometimes also works nicely, especially for very small stuff that doesn’t roll around.
Probably best not mixing those two options, since that will cause a lot of spilled parts some day 
STLs: Classic 1×1, 2×1 (long) and 1×2 (wide). I haven’t made a 2×2 yet, but just scaling the long one by another 50mm in height should do the trick.
Also available on thingiverse (thing 6796805)
Recommended label size is 48mm or 98mm for double-wide boxes.
Filament recommendation is clear PETG at the upper end of the temperature range the manufacturer recommends (in my case Sunlu at 240°C hotend/70°C bed). Works nicely with my 0.6mm nozzle and 0.4mm layer height and usually yields good see-through results without clouding, yellowing, gaps or zits.
