I split this off my other thing (https://www.thingiverse.com/thing:3091544) which is a bunch of organizer dividers for the Stanley 014725R 25 compartment organizer. This is an insert for the medium size bin, which provides 3 lidded compartments. I found I needed this when M3 nuts began to migrate to other places when I did a tip test using my divided bins. This part should print lid side down and has integrated supports so none should be necessary. Once done, remove the supports which close off the slots on each lid and insert the lid pulls (they should go in with the pull part towards the center of the box). The pulls have a dovetail and mine did not need any glue since they are a tight fit.

UPDATE 3/6/2021: I remixed this due to some issues folks have reported with the hinges. I printed several of the original version (the one here) and have not had issues, but the remix should resolve any issues with hinges being weak since it uses a bent paperclip as the hinge pin (a large paperclip is needed). You can find the remix which uses a paperclip hinge pin at the link below:

https://www.thingiverse.com/thing:4784172

I printed mine with 0.15 LH and 30% infill.

I used some 3m 468MP double sided tape around the top of the insert and near the bottom sides of the yellow bins to secure this in place. So after a test fit without tape, I applied the tape and pushed the insert in place rather swiftly, otherwise the tape will bind up on the sides.

I used the hinge from mathgrrl's customize-able thing, so it will print in one part.

https://www.thingiverse.com/thing:436737/files

Update 9/13/2018: There is a new (and now updated) 6 compartment model which is untested but I am posting it here in case somebody wants to try it. The first version of this 6 compartment model did not provide enough space between the compartment dividers and the doors so they were stuck together, the version now here should give a gap of 2 layers when printing at 0.15 LH. I found that the prior version from 9/12 did not have the supports so I uploaded the current version (MED-BOX-WITH-LID-3E2-6c-short.stl) which is the latest. I don't need this so will not be printing it.

Update 10/1/2018: Uploaded the STEP files to make it simpler to remix.

RELATED THINGS:

Stanley 014725R organizer - large 3 compartment bin with lids plus 4 bins
https://www.thingiverse.com/thing:3097911

Stanley 014725R organizer bin dividers
https://www.thingiverse.com/thing:3091544

Be sure to check out the remix by burgerga linked below which looks great and is a full replacement bin with a wire hinge pin:

https://www.thingiverse.com/thing:4460235

If you find these models useful, please post a like or a comment with some pics of your prints.

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Thanks for looking!