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Melvin/Projects/Better Loop

Prototyping a self-service 3D printer for repair parts

A self-service machine for supermarkets and a marketplace of printable repair parts, starting from a modified 3D printer.

Category
Hardware · Ventures
Organization
Better Loop, own venture
Status
Stopped
Dates
2025 – 2026
Concept render of the machine in a shopping centre: a lit glass cabinet with a 3D printer running inside it, and a passer-by stopped to watch.
Where the machine was meant to stand, a lit cabinet in a mall concourse that prints while you finish your shopping. Concept render, generated with AI.

The idea

A machine in the place where you already shop. It prints the part that just broke, a knob, a hinge, a clip or a filter, out of recycled plastic while you finish the groceries. There is no freight, no warehouse and no packaging, because the part is made a hundred metres from the person who needs it. Repair parts were the starting point, but the same machine prints interior pieces and toys.

The machine

I started from a Peopoly Magneto X, an FDM printer that already runs on linear rails, and modelled what an unattended machine in a public space still needed. That meant two modifications, both drawn in Fusion 360, and they did not get equally far. The tool changer stayed a model. Every part was designed, but I never got to the electronics and the wiring, so it never changed a tool. The part ejection went all the way. I printed the parts, fitted the motor and wired it, and at the end of a job it pushed the finished part off the plate by itself. Speed was the problem I did not solve. A shopper in a mall will not wait around for a print to finish.

The tool changer, modelled but never wired

CAD render of the print head: extruder motor and cooling fan above, a carriage riding twin linear rails, and moulded ducts curving around the nozzle.
Modelled down to the last part in Fusion 360. The electronics and the wiring were never done, so it never changed a tool.

The ejection system, printed, motorised and working

CAD render of the build platform: a belt stretched between two rollers on an aluminium frame, with two arced sweep arms on rails beside it.
This one I finished. Parts printed, motor fitted, wiring done. At the end of a job it pushed the part off the plate on its own.

The marketplace

Behind the machine there was a site. You search for your appliance, find the part, check its size, then choose which printer runs it and when. Tutorials sat next to the parts, because nobody buys a part they cannot fit themselves. The site was built and working, but I never opened it to the public.

Search by appliance, not by part number

The Better Loop site: a green hero reading “Sustainable Repairs for a Better Future” over a search bar for an appliance or part, with washing machine drum, dishwasher filter and refrigerator handle offered as popular searches.
You start from the appliance, because someone who has just broken a knob does not know its part number.

Then pick which machine prints it

The “Schedule 3D Print” dialog open over a part page: name, email and phone fields, a List/Map toggle, and a map of Paris with printer locations pinned on it.
Contact details, then the machine and the time slot. Built and working, but never opened to the public.

Why it stopped

The engineering did not stop it. I wrote the full business plan, and every version of it said the same thing. This is hardware, every machine has to be paid for before it earns anything, and that capex would have been mine to fund. It was too much money for the risk. So I stopped there. The CAD, the working ejection system and the business plan are all on file, and I am not taking it further.