When I was younger I had the arrogance and certainty of youth.

If you had asked me then what I thought of grown men still interested in model trains, I would have immediately dismissed them as social inadequates, stuck in their parents' lofts mindlessly watching children's toys going round and round and round.

The only models I was interested in then wore fake fur coats, hung about Charlie Parker's bar in Glasgow, and appeared on the sides of Tennent's lager cans.

Now I hope I am more tolerant, more able to see the point of view of others. So at the weekend I took my open mind to Model Rail Scotland at Glasgow's SECC where a surprising, to me anyway, crowd of 15,000 folk turned up to talk of double O gauges, three-link chain connectors, and digital command controls. Or, like me, to stare in awe at the complexity and detailed work put in to the model rail displays that had been set up by the 30 or so model rail clubs in Scotland.

The displays are usually oval with two or three club members quietly working away in the middle. The back of the display is an open working area where the trains are set up and sent on their way. The front of the oval is where the detailed work has gone in, meticulously planning the scenery around the tracks. It is clear that many modellers spend more time on the scenery than they ever spend actually running a train around it.

One scene has a hotel across the road from the railway. Sound a bit boring? Well the hotel is on fire with fake smoke and flames while a model fire engine with extending ladder is pulled up outside with firefighters attacking the blaze. Another, to show it is bang up to date, has working wind turbines slowly revolving on the hill behind the train track. Others have buses running on the road behind the track. I don't even know how they do that.

I spot a display of Glasgow trams, running past Glasgow tenements. This is particularly popular as the Glasgow South club allows children to control the trams. Naturally the kids ramp up the power as much as they can, and the trams skitter around the layout at a speed which I'm fairly sure they never achieved in real life. The Glasgow South club is an interesting one. It began as a club at Weir Pumps where skilled craftsmen, who made giant commercial pumps during the day, would fashion these little models in the evening.

Eventually the club parted company with Weir's but then took advantage of ScotRail's Adopt A Station scheme. What a great wheeze this is. Sorry, not wheeze, community involvement. ScotRail kindly allows organisations to take over a station and they usually spend their time tarting it up with hanging baskets and shrubs. Wonder if anyone would be interested in my Adopt A Garden scheme, saving me a lot of weekend work. But I digress. The Glasgow South Model Railway Club took over Maxwell Park Station, put in their own power supply, and run their modelling club inside it.

The tram display, like many others, has to be dismantled in sections then rebuilt at the SECC. The trams though have a power supply from overhead wires, so when it is reassembled, the wires have to be patiently re-soldered together again.

Another club, The Clydesdale, has a more impressive address, operating from within the bowels of Central Station in Glasgow. Its display at the SECC is of a Swiss layout where flash continental trains have to climb hills, cross bridges and disappear into tunnels. Other displays have details you could easily miss. One railway bridge has a tiny worker on it doing repairs. A rock-face has miniature climbers roped together.

So who are these people who spend so much of their time on model railways? Colin Rae from the Falkirk club, is in his thirties and works in IT for his day job. His main interest is painting the model engines. Not just splashing paint all over them, but getting the detailed colour schemes of the various rail companies and reproducing them to scale. He shows me one of his engines which has an authentic red painted line running around the engine no thicker than a line drawn with a pencil. "How do you get it so straight?" I ask. "Masking tape," he replies. I can't imagine how long it takes to fit masking tape that small.

So why does he do it, I ask. "I see it as great escapism," he finally replies after having to think about it. "Doing your day job can be quite stressful at times reaching deadlines. If IT systems break down, it can cost companies thousands of pounds. So when I'm at home painting you can switch off to the outside world. It's great."

Enthusiasts often join clubs as there they meet electricians, carpenters and other skilled people who can give advice on their own set-ups. A club will usually have a room somewhere where the come together to build a display to put on show. After a few years of taking the display around various shows around the country they will dismantle it and start again.

I spot that Hornby has a large stall at the SECC show. Hornby! Didn't realise they still existed. My clockwork train set was Hornby. My mother gave it away. Am still gutted. It's had its ups and downs has Hornby, but has now moved production to China. Train sets based on Thomas the Tank Engine and Harry Potter's Hogwarts Express helped save them.

So time to leave before I get all nostalgic and buy myself a new train set. After all, Charlie Parker's bar no longer exists so maybe I have time for a new hobby.