Solid storage box with origami folding lids.

Update 23-09-2024:

I've made a version 2 of the box. It prints faster, is stonger, no supports with printing, PiP lids and my opinion: it's even more beautifull…

You can find V2 HERE

This is the sequel to my earlier Luxurious Storage Box with Origami Folding Lid(s)

I have completely gone back to basics with the aim of creating the same effect but now with fully mechanical working parts.
So without bending single-layer flexible hinges, without spring constructions to secure the axles and without magnets to clamp.

Everything is 100% printable and much more robust.
The design is also more forgiving for less well-tuned printers and there is no need for a prescribed orientation for the print paths.

The hinges are integrated within the thickness of the lids and the box even contains a mechanical locking of the lids without spring parts.

Operation of the lids.

Although I suspect that most visitors will have seen the short video with my earlier design, below is an impression of how the lids work.

(BTW that video was already approaching 10,000 views at the time of writing this post. A larger number than I ever imagined!)

Note that the lids are now divided differently. I had to do this to prevent the angle that the parts make remained less than 90°, the maximum angle possible with the hinges. With the previous model, a Z shape was created due to the division there.

Printing

The lid parts.

The lids now consist of three separate parts that have to be assembled afterwards.
The two front parts (part 3L and 3R) are NOT the same! This is because the holes are slotted to achieve the mechanical locking of the lids.
Part 3L is marked "L" on the side.
Part 1 & 2 must both be printed 2x.

For the different parts and the correct orientation on the bed, see the image below.
Printed in PLA, nozzle 0.4, layer thickness 0.2, infill 30% and support everywhere.

After printing, all support residues must be removed. Do this thoroughly. There is often some extra residue on the axles due to the use of support. If necessary, cut this off so that the shaft becomes as round as possible. Make sure that the ends of the axle are slightly chamfered so that they can be mounted easily.

The Knob, Lock and Axle Lock

You need 1x the Knob & Lock and 2x the Axle Lock

For the different parts and the correct orientation on the bed, see the image below.

Printed in PLA, nozzle 0.4, layer thickness 0.2, infill 30% and no support.

The Box

For orientation on the bed, see the image below.

Printed in PLA, nozzle 0.4, layer thickness 0.2, infill 30% and no support.

Assembly

The lids

Slide the different parts of the lid together. Pay close attention to the orientation! This is indicated in the image below. Notice that the shafts are pointing upwards!
Once pushed together, the recess in the shaft falls over the cam in the opposite part, securing the two parts against sliding apart.

Mounting the Knob and Lock

See image below. Notice that the axles are pointing downwards.

Push the knob through both holes in the lids. Then press the Lock from below over both axes of the Knob.
To obtain a firm anchoring, you can first put a drop of glue in both holes of the Lock and then press firmly.

Mounting the Lids on the Box

Place both axes of the lids in the holes of the Box.
Rotate both lids to create an open Box.
Now place both Axle Locks in the holes in both corners of the Box. The round part of the Axle Lock should be facing upwards.
You can use a little glue to keep them in place. Be careful not to glue the axles!

Operation of the mechanical lock.

The lock works by interlocking 2 small printed tabs.
Due to the rest position of the Knob, which is then vertical, they remain hooked together. By tilting the Knob backwards (which is possible through both slotted holes in the lids) they can unlock and you can open the lids.
When closing the lids, you must ensure that the Knob is well pressed and is vertical. To be sure, you can additional tilt the knob towards you. (see video below)

Box size and scaling

The size of the Box 200x100x50 (knob not included) was created after a number of test prints for the hinges. It turned out that with my printer and settings, a smooth and solid hinge was created at the current size. I managed to stay within that 200mm, so it can be printed by almost all printers.

But nevertheless the Box can be scaled. For FDM printing I would advise not to go below 80% (the size of the original box). This already gives a very large saving on material and printing time, while the hinges still remain strong enough. It may be that the hinges are less flexible or operate less smooth due to the layer thickness of 0.2mm. By printing with a smaller layer thickness and/or nozzle, can you probably improve this.

update 07-01: To test for scaling below 80% (max 60%) I added 2 cut-out testfiles of the working parts of the lids, so you don't have to print the whole lids to test! 

update 11-01: Kenshin861 successfully printed at 60% with nozzle 0.6 and layer thickness 0.2. See his make and read what he writes about it on thingiverse!

DLP printing.

This model is suitable for printing with DLP. Make sure you don't scale below 50% to leave enough strength for the hinges.
This does limit the use to DLP printers with a print bed of at least 100mm long and 50mm wide.

Pay close attention to the orientation of the parts. This allows you to minimize the amount of support needed.
With good placement you can make a complete box in 2 prints.

Update

Update 15-01:
It could happen that the Axle Lock was not pressed sufficiently against the axle. It was just 0.1-0.2mm but that is enough for the axle to come loose. I have removed a little bit from the Axle Lock so that this cannot happen again.

Update 23-01 (please read update 27-01 it may make this update unnecessary):

It may happen that the axle on Lid Part 1 breaks off (due to poor layer bonding). Because I received several reports of this, I have added lids with a hole for a small bolt from the other side trough the axle (so that it is not visible) for those who can't get the layer bonding right. After printing, a bolt M3x16 must be screwed into the axle as reinforcement. The bolt is tightened only in the part of the lid itself, clamping the axle against the lid. The bolt is not visible after mounting. The only thing you need to add to assemble the box are 2 bolts M3x16. The shape of the head is not important, as long as it is not higher than 3mm and thicker than Ø6. Be aware that this is only possible when printing at 100%!

Update 27-01

While the 23-01 update fixed the problem of bad layer bonding, it didn't really sit well with me. Wouldn't there be another solution to improve the layer bonding and thus be able to print the model 100% without adding hardware?

Well, I found a solution to force the slicer to change the layer build towards the shaft and also make the shaft itself much stronger. The technical explanations can be found on reddit where I posted them: [LINK]
I have updated Lid Part 1 with the new method. I think this is a universal solution that eliminates the need to use the previous update. For reference and history I will leave the previous update. This way you can always choose which solution seems better to you.