Today I have a very niche project and I hope the internet will not laugh at me. In my kitchen, I had a large laundry basket that I used not for laundry but for dirty dish towels. It took up a lot of space, but it matched the colours and the shape of the surroundings, so it stayed there for a few years. Still, I was wondering how to use the space better and more efficiently.

A few months ago, I discovered that the IKEA Råskog trolley fit that part of the kitchen almost to the millimetre. I bought it right away, but didn't assemble it because I was thinking about how to store dirty dish towels in it. I really didn't want them lying around the kitchen or visible from the trolley.

I came up with the idea of an enclosed floor between the lower and middle floors. It would simply be 3D modelled somehow, 3D printed, and done :) The individual floors of the cart are perforated, so if it fully closes, air will still flow through the top and bottom floors. It sounded brilliant, but it would be hell to 3D model it – I knew that from the beginning.

It took a few months for me to start working on it properly. I was thinking about it somewhere in my subconscious mind. First, I had to find the dimensions inside the cart, in the inner wall of the lower floor. It turned out that each floor was a few millimetres off and different in each corner. This was even worse than I had thought. I tried to measure it with those shapers to cut out the corners of the tiles. That didn't work because the shapers didn't have the dimensions I needed.

Then I tried to simply trace the floor plan on paper and estimate the thickness of the walls. That was a bit more hopeful, but I needed to verify that it fit.

I cut out the floor plan, put it directly into the lower floor a few times, and checked the fit. If it didn’t fit, I cut it a bit again. There were about ten iterations like that, but I already had a vague idea of the dimensions!

Though the cart turned out to be really, really crooked, I wanted my creation to be accurate. I wasn’t going to pass on that crookedness. So, I 3D modelled the individual parts mirrored and then printed the test shapes on my 3D printer. I tested narrow pieces to see if they fit in the trolley before printing the whole big wall.

I calculated that the entire floor could be done from four prints. It was the limit of my 3D printer, which can print a maximum of 21 by 25 centimetres. I started with the 3D modelling of the whole thing. Let me tell you: It was a puzzler. I had to think about dozens of things at once: where it would be connected and glued, how it would be printed, the shape of the trolley, the screw holes, the closing mechanism…

Yes, on top of all that, I wanted a closing door. The closed floor itself would have a hole with a moving door that I would use to hide the towels in the trolley. If I'm going to do something, I’m going to do it properly!

The final model was out and the printing took days. It was one of the more difficult prints; I had to constantly adjust it to make it fit. Do you remember that I said it had to be precise? In the end, one printed wall is a few millimetres shorter than the parallel opposite one. But it fits and I made my peace with that.

The walls are four millimetres thick to support the second (middle) floor. When I found that it somehow fit together, I started glueing everything. I used modelling glue from Pecka and waited about a day for all the pieces to come together.

My chin dropped as it all clicked into place. I was in a phase when I’d stopped hoping it would all work out, but it did, and it looks great! There's a catch, though – when I tried to put the same body on a different floor, just for a test, it didn't fit. The floors of that trolley are so crooked, they don't have the same floor plan, unfortunately.

I knew I would use the cart's top floor for resealable bags. I don't know what I’ll do with the middle one yet, but some things are starting to appear by themselves there. By the way, the heater the cart is next to hasn't been turned on for years, so there's no need to worry about the PLA material not enjoying being near it.

Here is the before and after comparison. I dare anyone to say that it was better before! :)

STL file

• Closing shelf in IKEA RÅSKOG trolley