In an effort to continue to make entertaining, prank gift boxes (see my earlier attempt), I came across this Really Annoying Gift Box by Thin Air 3D. There’s nothing tricky or puzzling about this gift box, it just has a LOT of screws that must be removed in order to reach the gift. I was put off a bit by the high price tag of these products, so I thought I’d design and build my own. Then, I came across some free 3D print files from Mechengg and decided to use that instead as it would save me a lot of design work.
Using 2 3D printers, I was able to complete the print of all parts in under 3 days. I used extra filament I had available, opting for some fancier colors. My intention was to do minor clean-up and not finish the 3D prints so those fun colours can be enjoyed. Of course, that means lots of visible layer lines, which I’m just going to have to get over.
Assembly Process
The box has 3 layers, so I picked different colours for each layer. For the inner layer I used silver. For the middle layer, I used white, for the outer layer, I used “Galaxy Black” and for the ribbon, I used Copper. All these colors were PLA, so quite easy to work with.
As you might expect, the process starts with the assembly of the inner box. I printed this using “Galaxy Silver” PLA filament from Prusa which came with my first 3D printer. It’s been sitting in a low-humidity box for years, so I’m pleasantly surprised it cooperated for this print. The lid has 4 rods that slide into the body. I used 2-part epoxy to secure these rods into place, being careful not to have any squeeze out that would prevent a flush fit of the lid. 20 x 10mm screws secure the top, and then you flip it over and 4 screws secure the rods.
Next comes the middle layer that I made from white PLA+ because I have a LOT of it on hand for another project. I would have preferred another fancy colour, but didn’t have any on hand and didn’t want to buy new. First, you must insert the special screw posts on the inside of each half of the middle box before sliding them over the inner box. I found that the halves are not perfect squares so I had to rotate 90 degrees to avoid a 1mm overhang that would have prevented the next layer from fitting well. 4 columns x 4 rows of screws per side requires a total of 64 x 10mm screws for this layer. The inner most columns on each side are not countersunk because they are used for the next layer, so they are left open.
Next comes the outer layer. This “Galaxy Black” PLA I used is really fantastic. It came with my Prusa 3D printer and this is the first time I’ve used it – just beautiful. The two halves of the outer shell slide over top of the. Semi-circles on each side are cut out to accommodate the screw posts from the 2nd layer. 2 columns of 4 rows of screw holes per side require a total of 32 x 17mm screws. These screw holes are not countersunk, so stand proud on the surface.
Finally, the finishing touch – the ribbon. The 4 U-shaped ribbon pieces slide over top of the outer shell to hide the screws. I printed this with Hatchbox’s “Copper” PLA filament. Each of the four ribbon pieces has an interior pocket to accommodate the proud screw heads from the outer shell layer. The bow goes on top and screws into the screw post from the middle layer. Another cap screws onto the bottom and secures the ribbon pieces nicely.
Total time required to do the assembly using a flat-head screw driver (.STLs provided) was about 20 minutes. Novice disassembly time was about 12 minutes.
Conclusions
Overall, this was fun to print and assemble. I highly recommend for anyone who has the means. I hope the recipient enjoys it in the spirit it was intended. Here are some concluding thoughts:
- Heavy – the final, assembled weight is about 8 pounds without a gift. This is much heavier than I expected. I used 0.2mm layer height, 3 permitters, and 10% infill on all parts to keep the weight down, so a bit surprised. I’m not sure I would back down these settings as it would impact the finish. Note – there was one exception – I did use 100% infill on the middle box screw posts because during a disassembly, I easily snapped the post.
- Too big – The 4″x4″x4″ interior dimension is much bigger than I needed for a simple gift card. I probably should have selected a different style that was smaller. Perhaps, I’ll need to find a bigger gift now?
- Adhesion – I had some 3D printer bed adhesion issues with some of the bigger prints. I know I could solve this by using glue on the printer bed, but I never had this issue before with this printer, so surprised it happened. Luckily, it did not impact the fit of the layers or the screw holes, so I’m not going to reprint.
- The minimal-stop, 72-hour print time was longer than I expected. Even though there was no finishing time/effort, this project still required a notable time and material investment. While it’s clear that some margin was added to the price of the original “Really Annoying Gift Box”, it probably is not as much as I originally thought.
- Clean-up – I was not intended to sand/finish the prints, but found that every layer ended up having a print anomaly that needed to be corrected for the boxes to fit well. The layer that transitions from bottom to walls seems to have a small offset which creates a ridge around the whole print. I knife scrape quickly addresses the issue, but the design might want to investigate this issue.
- Epoxy – No assembly instructions were provided, but it seemed logical that the inner box lid should have the 4 posts epoxied or the screws would be free-spinning. Also, I chose to epoxy the ribbon to the top cap and re-enforce it with a small screw. Having the leverage helps with the disassembly and I didn’t want these parts breaking apart.
- Quantity – the instructions are to print “lots” of screws, but it was left to me to determine how many of what colour and what length. So, through experimentation, I learned the correct quantities and lengths (listed above).
- Modified .STL – the .STLs provided have a design for the wrap end caps to have a slot in them which is used on the top to hold the ribbon. However, the bottom has no ribbon so does not need the slot. I modified the .STL in Tinkercad to fill in the slot and printed a special version which, I think, looks nicer.
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