“F*n**g* f*ng ** fgr** gnr**,” I reply.

There is a cursory discussion - with the emphasis on curse - after which the wife retires to a safe distance (January sales), leaving me to contemplate shoving my cross-head screwdriver where the author of this instruction manual wouldn’t like it. And if it results in brain damage, so much the better.

DIY is not my thing. It never has been and it never will be. It’s not that I do it to save money either, because by the time I’ve paid the guys to come round and put things right, I’m usually a lot more out of pocket than I would have been had I hired them in the first place.

The main problem is that I’m not by nature a practical person. In educational parlance, I’m about as un-kinaesthetic as a person is likely to get. I’m not even good at spatial awareness - as the guy standing behind me when I carried the self-assembly wardrobe out of the shop will testify. At least he will once he’s over the concussion.

The motivation behind my tendency towards DIY is something I’ve given a lot of thought to just lately. I especially thought about it when I realised that I’d inserted section B into section A the wrong way round, thus necessitating the complete disassembly of sections C, D and E.

The truth is, I usually don’t do it myself. “A man’s got to know his limitations,” said the great Clint Eastwood, and believe me I know mine.

And if I were a fighter pilot or a train driver, or even a bin-man, the chances are I would stick pins in my eyelids before electing to wander around a self-assembly furniture shop.

But that’s the problem: I’m not a fighter pilot. I’m not anything even remotely macho. I’m a male primary teacher: a dying breed and an educational dinosaur. I’m a man in a profession in which men are as rare as British sporting triumphs, and whose motives should therefore be viewed with suspicion.

This occasional urge to assemble a flat-pack or lay down a laminate floor is but the manifestation of a biological need to assert my manhood. What drives me, I suspect, is some ancient gene, buried in some forgotten Y chromosome, in a tiny cell secreted deep in my testicular region.

Now and then, when the moon is full and bright and the seven o’clock shadow starts to lengthen, vestigial pieces of caveman DNA come spiralling out of the depths with all the ferocity of a shark attack and urge me on to manlier things.

“Go on, my son. Get yourself down to BQ an’ pick up a flat-pack... an’ while you’re there, get yourself a tool-belt, an’ a socket set, an’ one o’ them multi-purpose whotsits on special offer wiv 50 different attachments and a picture of Handy Andy on the front. Go on! Whotcha waitin’ for?”

Steve Eddison is a Year 6 teacher in Sheffield