What was the best part of working on The Re-Inventors?
One of the biggest things for me was working with James. By the time your youngsters go off to university they've often flown the nest for good. This way, we've done a lot of really different, interesting things together. I'm the engineering, grumpy one and James has got all the historical and arty bits. We're nothing like the same but we managed to work together.

Some viewers suspect that challenge-based shows such as The Re-Inventors have a team of experts in the background who secretly do all the work while the presenters take it easy. What do you say to that?
No such luck! There are no little elves to come along and make us look good. We do the actual work to complete the challenges. We bleed all over the place for The Re-Inventors!

For the show, you developed your own mobile workshop out of an old horsebox. Tell us about that.
It's got a hydraulic ramp on the side and, inside, we installed our own workbench. And we filled it to the brim with all sorts of tools and bits and pieces. It meant that we could go anywhere and take on any engineering challenge, rather than having to rely on other people to lend us tools and materials. That was a huge advantage for us. It was so full that sometimes we had problems shutting the door!

How did you come up with the idea for The Re-Inventors?
It all started off as an idea for re-inventing a Victorian device - the Teasmade. It was a wacky enough concept but in time we realised that we had to think bigger. So the series evolved along the lines of 'How big can you get?' And it doesn't get much bigger than Stephenson's rocket, does it?

What was the toughest challenge you faced?
Either going up against the rocket or re-inventing the power loom (designed by Edmund Cartwright in 1788). We didn't have enough time to get our gearing for the loom sorted out. We came up with a system that was fairly similar to the one that was being used in the mill but we just didn't have enough time to perfect it. We had quite a race on our hands when it came to pitting our machine - made of plywood and sticks - against the phenomenal power of the Queen Street Mill, a working textile museum in Burnley. There are 300 looms working off one enormous steam engine. At its height, the mill would have had 1,000 looms in operation. Just think of the noise. This was the power that helped make Britain great.

Re-Inventing Stephenson's rocket must have been a daunting prospect.
From an engineering point of view, re-inventing the Rocket was my favourite challenge. Our valve timing system was brilliant. If we'd had another day or two, we could have made something that would have lasted. As it was, we came up with an engine made out of a big gas bottle, three bicycles, a couple of bits of copper tubing and some left-over plumbing.

You weren't afraid to improvise, were you?
Absolutely not. During our challenge to re-invent the fire pump (invented by Richard Newsham in 1718), the technical breakthrough came when James' research uncovered the secret of maintaining a constant flow of water. The original design used an expansion chamber which we re-created with an old soft drink bottle. Cracking that problem was a high point for me.

The inventors featured in the series are part of a great British tradition in the field. Have we still got that spirit of invention?
I think the British are still brilliant at inventions. Something like 55% of all commercial patents in the world are British. So why aren't we taking over the world? The reason is that, entrepreneurially, we don't do a lot with it. But, out there, people still have the ability to invent. Anybody is capable of invention. Mind you, having a good idea and then doing nothing with it - then you may as well not have had the good idea. This is the real difficulty - taking that step forward.

What makes good history television?
Seeing someone doing something is more powerful than trying to explain it to people. The sort of television we're making is full of what I call 'the sound of pennies dropping'. When we're racing and you see the original and you see our re-invention, then you have the opportunity for the viewer to make deductions about the experience, rather than being spoon-fed the answer. You have to be careful of employing soundbites that people can regurgitate without having used their brains. At the same time, it's got to make you smile because I don't like being miserable. If it's entertaining and if people learn from it, you're ticking two big boxes.