Lyndsey Morgan: When I was a child, my father took me to the Tate every weekend. The figure in Allen’s Chair (1969, pictured) really stuck in my mind because I was small and it was at my height, quite low on the ground. She seemed like this very beautiful lady. And then I next encountered the work at Tate with its damaged face.

Yes. I had to undertake a large project as part of my internship, and I had a choice of three sculptures. One was a Henry Moore stone piece, the other was a terracotta bust, and then the third one was Chair. I remembered it from when I was a child, and I was shocked to see this massive change. Suddenly to see the work in this condition made me think, ‘I want to do something about that’.

The attack was in 1986. The figure is glass-reinforced, polyester resin, painted in various layers with acrylic paint. When it was vandalised (during the exhibition Forty Years of Modern Art, 1945-85), two bottles of paint stripper were thrown at it, and then the attackers ran away. The paint stripper landed – whether by coincidence or design – on the face and on the top part of the body, and it melted the paint. All that was there became wrinkled and badly discoloured, and the resin underneath was very badly pitted. The figure’s gloves were also damaged; the paint stripper splashed onto the gloves and the boots, and so all of the clothing had to be taken off.

More or less immediately. He was very willing to come in and talk. I assumed he would want it to be restored, but I realised that he hadn’t been asked at that point.

His intention was for it to look super-real, very perfect. His first comment was that he wanted it either to be fully repainted, or to be fully recreated if that couldn’t be done. But in conservation, we are always trying to preserve as much as we can of the original, so I asked if I could try to retouch the sculpture. Allen came back in to see some of the work while it was happening. He was very happy with the restoration as it proceeded, and gave me lots of information about it. I’ve since worked with Allen in the fabrication of several of his figures.

I hadn’t realised how much of the clothing had been made bespoke for the figure. Apart from the gloves, which were bought from a shop (S Weiss, formerly located in Shaftesbury Avenue), everything was custom made. The boots had been made to measure for the figure. The leather was by John Sutcliffe. We had to get all the clothing back on again, which was quite an operation in itself. I hadn’t realised how difficult it would be to get a pair of long lace- up boots onto a figure that doesn’t move. The figure itself had been made in clay by Dick Beech at Gems Wax Models, and then the cast was taken from the clay model.

I thought, ‘What a fantastic opportunity.’ The piece didn’t offend me. In my field of work I’ve been shocked by other things far more. By that time it was well established as an iconic piece of Pop art. I was excited to be working on it, rather than having any problems about it.

Yes, I have. There are interesting remarks, such as, ‘Why did you not leave the damage as a mark of the work’s history?’ But it was such a dramatic and violent change, so I answer no. I feel quite strongly about vandalism – I don’t think that anybody has the right to edit art history.

Others have said, ‘How could you work on this piece?’ because they feel that it’s degrading in some way. But I think that is looking at the issue far too simplistically. It’s an interesting window onto late 1960s London, and it’s easy to see it in the wrong way, as very little of that world now survives. It’s quite hard for us to understand at this moment how things were then, and I think it’s more important than ever to get a sense of the work with all its nuances and historical context. For me, it’s a groundbreaking sculpture because of the way in which its hyper-realism provokes the viewer to react to it. I believe that, without Chair, we wouldn’t have the hyper-real works of Jeff Koons, Ron Mueck and the Chapman Brothers.

Alison Bracker is an art historian.

Watch an interview with Allen Jones RA in his Oxfordshire studio. Allen Jones RA is on at Burlington Gardens until 25 January 2015.