Jacob D asks: Ever since I was a child and received my first science set and a small book about past inventors, I have always wanted to be an inventor.

I’ve had a fascination with energy, particularly free energy and perpetual motion. I’ve drawn hundreds of diagrams, made 3D models and had several trial runs with various small structures containing aligned magnets.

What would you recommend to help me to find that one idea? Should I continue in the same field or should I broaden my experiments?

James Dyson: It sounds like you have a real passion for inventing things. Unlike you, I had no such aspirations as a boy. I pored over copies of Eagle magazine, became fascinated with how things work — but didn’t realise I could make a career out of this until much later. Engineers were people who fixed things, weren’t they?

I think you need to match your specific passion with a problem. I take my inspiration from frustration; I like finding solutions to annoyances.

My advice would be to concentrate on your interests, but don’t be afraid to follow them in new directions. Sometimes the best ideas come from mistakes and observations. I like the story that Charles Goodyear, who discovered, after years of trying, the process of vulcanising rubber when he dropped a mixture in his stove by accident. You don’t know where your ideas and experiments may take you.

Lydia Cottrell asks: How do I get your help for an invention that I have? I have a provisional already and will soon have a Frankenstein prototype ready. What shall I do from there?

James Dyson: I like the idea of your Frankenstein model — it sounds ugly, which in my mind is spot-on. Your prototype should be about how it works, not aesthetics. If it works, that’s what matters.

Now, I would go so far as to say that, if you can, develop it alone. When I was in your position I thought I needed the backing of the big boys. But the net result was years wasted trying to persuade others to take on my idea. Part of the problem is that investors will distrust the idea if it’s being posed by an engineer or inventor rather than a marketer or business professional (I’d even tried wearing a tie!).

It’s hard in the current climate, but challenge yourself to see how far you can take it on your own. I launched my first vacuum cleaner in a recession, although it should be said that I didn’t get out of the red until my 40s. You’ll face setbacks, rejection and debt, but take the risk: you’ll find people are still willing to invest in good technology.

Chris Hammersley asks: Do you have any examples of a sound non-disclosure agreement? Do they work, or is it down to luck and a healthy dose of caution, if not paranoia? What can you really do if someone violates your trust?

James Dyson: You’re right to be cautious; protecting your idea is paramount. Before you reveal all, or indeed anything, to a third party, make sure that your intellectual property has your name on it — file a patent.

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