Parametric eppendor PCR tube box with lid

About this design:

I think this box has many cool features, but I want to highlight just one. You can easily modify it to suit your liking. I have wanted to step up my modeling game and design something where I could quickly modify one thing and don't have to adjust five other things. So this design is me learning to use the spreadsheet functionality in FreeCad. I have highlighted in cyan all the parameters that you can change to suit your liking, the rest are parameters that are calculated based on other things.

So you can change this:

to this:

in matter of seconds. You don't even have to know how FreeCad works pretty much. Just click on Spreadsheet, modify values (takes a second to recalculate the model) and then export the plate, bottom and top.

Instructions for printing:

• I use 0.3mm layer height for speed and black PLA+.

1.Print your plate first!

2. When printing the large bottom part of the box, add pause to the layer with blue outline (bridge), close to the top of the part. (Pre-sliced gcode already has this pause)

3. When print pauses, insert the plate and resume.

4. Assembly the print and insert filament into hinge space.

5. If the box doesn't want to stay fully closed on its own (I'm still working on this issue). I have two solutions.

5.1 Tape the box shut for a few days, the PLA gives up its small rebelion and deforms accordingly. 

5.2 If you hate waiting, you can dip just the hinge part in hot water for a few seconds, while the box is taped/held shut. Just be careful to heat only hinge part, so that you don't deform other parts of the box. (I use small mug that is filled to the brim with hot water)