I was born with Poland syndrome, a disease that prevented the formation of my right arm and pectoral muscles. I was bullied at school. People said things like, “It’s not your fault that you were born like this, it’s your mother’s fault.” Or asked me to catch a ball with my right hand. Stupid comments that wouldn’t affect me now, but back then they struck very hard.

I would play with Lego a lot as a child. I got my first kit when I was five. My parents realised it was a great way to improve my dexterity. I just kept going, building planes and cars. I even built a guitar.

I was obsessed with videos on the internet about Lego Technic – a more advanced range – and how to use it to build stuff like guns that shoot rubber bands. When I was nine, I built my first prosthetic arm from Lego Technic. My first prosthetic was a simple box that I could fit my arm inside.

I lost interest in Lego for a few years, but when I was 17 I picked it up again and made another prosthetic that I called the MK-1, which had fingers, a motor and a pressure sensor. It had a movable elbow joint and grabber that could pick things up.

Before I built my first arm, I had already decided I didn’t need a prosthetic. My parents and I had looked into getting one a few years earlier, but I realised they were very expensive and weren’t provided by the government. So I thought, maybe I don’t need one because I’m doing just fine. I look a little bit different, but that’s OK. It’s kind of ironic that I don’t use the prosthetics myself, but by the time I started making them I had already adapted to my condition. I make them because it’s fun.

I have since made several new versions. My latest model, the MK-V, is the most advanced and comfortable yet. It has a control unit that can send and receive orders from sensors on the arm to the motors, with cables that contract like muscles.

I named my prosthetics MK in tribute to the comic book superhero Iron Man and his MK armour suits. My creations are very strong and robust. I wanted to check how easy it was to break a prosthetic, so I started to hit it against a wall – it was the wall that ended up damaged.

We made a video about my creations and it went viral. At 23, I’m the Guinness world record-holder for being the first person to build his own fully functioning prosthetic arm using Lego bricks. A documentary has been made about me and my dad, and I have just written a book about my life.

I have a YouTube channel, Hand Solo, where I share videos of my work so others can learn. I was slightly worried about using the Star Wars name, but my dad wrote a letter to Disney, which owns the rights, explaining my situation and it agreed to let me keep the name.

A lot of people don’t have the resources to buy a prosthetic because they can be very expensive. Some prosthetics are cheaper than others, but the top-notch advanced models can cost as much as an Aston Martin. So my goal is to try to make some that are more affordable. I am currently studying bioengineering, and through my studies, I hope to help more people.

When I was 19, the parents of an eight-year-old boy with phocomelia had seen my work and got in touch to ask if I could build him a prosthetic. His arms and legs are underdeveloped as part of his condition, so I made two prosthetic arms using Lego units costing only €15. His smile when he used them for the first time was very empowering. I’ve had many requests to make prosthetics, but I have to spend time thinking about the design and utility.

I don’t like injustice in life, such as bullying, or the fact that someone may have to pay up to €100,000 for a prosthetic. People shouldn’t pay that much – it’s not a luxury.

To me, my creations don’t necessarily tell the story of how I overcame my condition with Lego; they’re about how I overcame bullying and being upset almost every day at school. Now I feel as if I am Thor, and my prosthetic creations are my hammer.

• As told to Daniel Dylan Wray

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