John Constable is best known for paintings like The Hay Wain, but a very different piece of his life is about to be heard again.

The artist’s personal cello, commissioned by Constable and made in 1802, is set to be played in public for the first time in 100 years after restoration. It is thought he may have played it in a local band in his home village of East Bergholt in Suffolk.

The instrument was made by John Dunthorne Sr, Constable’s neighbour, early mentor and friend. Dunthorne worked as a plumber, glazier and carpenter, but he was also a painter and maker of musical instruments.

The two men painted together in the lanes and fields of East Bergholt, and their letters show a long friendship. In 1799, Constable told Dunthorne he had been accepted into the Royal Academy Schools, adding: “I hope by the time the leaves are on the trees, I shall be better qualified to attack them than I was last summer.”

The year 1802 was significant for Constable. It was the year he wrote about becoming a “natural painter” and had his first work accepted at the Royal Academy, catalogued as “A Landscape”.

A page in one of Constable’s sketchbooks shows two musicians, including a cellist, which art historians suggest could possibly be the artist and his instrument. Small wooden figures, thought to have been carved and painted by Constable in his youth, are believed to represent singers of the East Bergholt church choir.

The cello entered the Ipswich Collection, owned by the local council, in 1942. It had been badly restored in 1926 and was no longer playable.

Now, 100 years later, the Friends of Ipswich Museum have raised more than £4,000 to pay for its restoration.

Emma Roodhouse, a curator at Colchester and Ipswich Museums, said the instrument was recorded as having been made for Constable.

“It’s remarkable in that it survives with all its fittings,” she said.

“Dunthorne was really pivotal for Constable. He’s the figure early on in his career that encourages him and he’s the one that Constable turns to and writes some of his most poignant passages about the fact that he’s going to become this natural painter. But, as a working-class man who’s self-taught, I don’t think his story is as widely known.”

One contemporary wrote of Dunthorne: “Mr Dunthorne possessed more intelligence than is often found in the class of life to which he belonged.”

Constable’s letters show how much he valued the friendship. Writing from London in 1800, he told Dunthorne: “This fine weather almost makes me melancholy; it recalls so forcibly every scene we have visited and drawn together.”

Dunthorne outlived his wife, his four children and Constable. He died in 1844 and was buried at St Mary’s Church in East Bergholt. His obituary in the Ipswich Journal described him as a man of great ability.

Roodhouse said: “As a self-taught artist and musical instrument maker, he is worthy of more than just a side note in Constable’s story.”

The cello was restored by James and Sylvie Fawcett, restorers based in Suffolk. Cellist Melanie Woodcock, who grew up locally, has been playing it during the restoration.

“They have done the most fantastic job. It sounds better than we could have hoped for. It’s a very rich, lovely sound. I grew up locally. Constable’s very much of this area. Although he was an amateur musician, it’s incredible to think that it was his instrument and that he could have played it,” Woodcock said.

Woodcock will play the cello at a public event on 10 June, alongside readings by author Susan Owens from her new book on Constable. The instrument will then go on display at Christchurch Mansion in Ipswich from 17 June until 4 October as part of the year-long Constable 250 festival marking the 250th anniversary of his birth.

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