Creating a 3d printable toy for children may seem straightforward enough but when those children are seriously ill and undergoing painful procedures, suddenly every design decision matters. As I worked through prototyping just such a model for the Pieksekisten project, I had to consider and design around a number of requirements and challenges I don't normally come across. I went through at least 20 iterations:  the first 6 were complete failures, and the last five were optimistically (and incorrectly) labelled “final.” The finished model. Actually, I tell a lie. This is two versions ago. Prototype 16? 18?  I've lost count, actually While it's too easy to look at a polished design and think the creator just banged it out, there's more to it than that, often involving failures, mistakes, tunnel vision, questionable life choices, coffee, crippling self-doubt, and starting from scratch halfway through. Wait, that's just me. The IdeaI knew fairly quickly what I wanted to design for the project. A kit card. Not just any kit card, but a puppet theatre. A puppet theatre that was itself the card – the sprue – that held everything together. The puppets and legs would print with snap-off lines and the whole thing delivered to the child who would happily assemble it with their parent. The sketch. It was a PERFECT idea. Narrator: it was not, in fact, a perfect idea. Astute readers will note that the finished model is not a kit card.  This is called foreshadowing. The First BatchAt first, the idea was perfect. And then as each iteration tried to solve the problem of the previous one, it got farther and farther from what I wanted. Half-drunk cup of cold coffee for scale. This represents a week of tinkering.I gradually came to the conclusion my idea wasn't suitable for the project. In particular:Snapping off left sharp edgesNeeded an instruction sheetHinges tried to solve the sharp edge but they were big, clunky, broke easily, and/or hard to printTrying to print multicolour would be limiting the colour choicesNo place to store all the partsWobbly and prone to falling overI tried to make it work. I really did. It might still be useful for something else. Such as a cautionary tale or projectile. Or both.Back to the Drawing BoardIt's hard to admit your idea isn't working. Especially when you were so sure of it. After I sulked a bit, I decided I needed to draw up a list of  “must haves” and “nice to haves.” Hard requirements:Immediately ready to play withSelf-contained (everything had to store on board)No sharp edgesMinimal small partsEasy and quick to print with minimal AMS wasteNo difficult assembly steps or special hardwareSoft requirements:Swappable scenery backgrounds made with business cardsImmediately recognizable as a puppet theatreMulticolourInteractive in more than one wayThe Model Takes ShapeArmed with a shopping list, I booted up Fusion. While I'd like to say that I knew what I was going to do that's not what happened. I morosely faffed about and came up with this awkward thing.   Faffing about. Not enough room for puppets. But the sliding stage was okay…ish? I made it, but didn't like it. So I returned to my tried and true approach: procrastination cleverly disguised as research. I looked at a lot of photos of puppet theatres. New theatres, old theatres, theatre illustrations, full-sized theatres, tabletop theatres. Did you know there's a bajillion theatres out there? And I looked at all of them? It was only when I mashed two entirely different theatres together that I finally broke through the creative block. The first, an antique Victorian toy theatre with its elaborate designs and equally elaborate puppets. The second, a 1960s era Punch and Judy theatre toy with its compact house-like design, simple playfulness, and instant association with puppetry. I wondered if I could combine what I liked about the first (puppets attached to pasteboard strips which propelled them onto the stage) with the simple practicality of the second. With this in mind, I went back to Fusion, enabled productive faffing, reused the sliding stage idea, banged away for a few hours and created something I can only describe as…thick. The picture doesn't truly convey how chunky this thing was. There were problems – it took forever to print due to the excessively thick walls and the underside of the roof was a hot mess  –  but it felt like I was heading in the right direction.  I had learned from the first batch not to blindly tackle problems like whack-a-mole, but to instead slow down, look at the big picture and really think things through. What worked? What didn't? My next attempts were more slowly and thoughtfully created. I'd stop after each one to ask the questions, tossing what wasn't working, keeping what did. And always comparing against the hard requirements. Left side Good: stage is stationary now and only the floor slides, overhangs eliminated by removing ceiling entirely, the extension at the bottom of the stage gave it a bit of visual depth, having the stage front print flat meant it could have colour added to it with minimal AMS waste Bad: way too many parts, still too chunky, brackets felt weak, stage front only attached at the bottom (weak) Right side Good: lid less clunky, brackets replaced with tall bracing columns (more surface area for the dovetail), backdrop slot added Bad: still too big, curtain still required an AMS, the front columns not thick enough and might break, dovetail poorly sized, window shape is meh, lid too tight The Model CoalescesThe right-side model was the one that showed the most promise and so I decided to just go for it. I started a new fusion file, and started building “for real” this time. I fixed what I didn't like including figuring out how to make the curtain print separately. Sadly, I ditched the backdrop slot because it was causing problems in terms of ease of use, overall model size and so forth. I also added a two-colour effect to the front by making a raised border and stage extension that could be easily printed with a filament swap. You could say this was the point where having met the hard requirements, I could start on the soft ones as well. I sent it to print and crossed my fingers. When I pulled this off the printer, I had a thrill. This was IT. Finally. I had found the shape, the dimensions, the everything.At the time I thought I was a few cosmetic changes away from being done. Narrator: She was not, in fact, remotely close. After this first fully-realized, ready-to-polish (ha) model, I went through at least a dozen more iterations, going through the requirements each time to be sure I was on the right track. I even figured out a way to put the business cards back in business (😎👉👉) which pleased me to no end. I could go through each of the remaining prototypes, but it's late, I'm tired, and this is long already. Instead, I'll sum up all the important bits with my favourite and yours: the instructional diagram. And if you think this is a lot, I haven't even mentioned the lid, the ungodly amount of time I spent researching global business card sizes, or having to go back in and redo both PDFs from scratch because of a big mistake 🤪But finally it was done. The finished model.  Actually…I tell I lie. This was one version ago.What could I have possibly changed at this late hour? (The lid. Always the lid.) Puppets for PieksekistenIn the end, the theatre had to go through many versions to get to what I thought was impossible: all the requirements – hard and soft – achieved. While I was initially deflated about giving up what I wanted to do, the final result is better for it. While no one can guarantee how a toy will fare in the hands of a child or even in the environs of a hospital ward, I can at least guarantee that this is the most over-engineered puppet theatre I've ever made.* I hope you…enjoyed?…this particularly deep dive into prototyping. If you have any prototyping stories of your own, I'd love to hear them!     (Is joke! I only made one puppet theatre and it's this one!) https://makerworld.com/en/models/2753762