James Stewart hired the JCB machines from stores in Cupar and St Andrews last year - handing over his own name and address details to take away the diggers.
He then sold them on and spent the money funding his betting habit and on booze.
Stewart fobbed off the owners with excuses before ignoring their calls.
Police were called in and were able to track one of the diggers to a traveller’s site in Aberdeenshire and another to an industrial estate in Kirkcaldy.
The third - valued at £21,000 - has never been found after the stunt, branded a “foolish plan to make money” by his own lawyer.
Now Stewart will miss the birth of his child, due later this month, after he was sentenced to a year in prison at Dundee Sheriff Court today.
Fiscal depute Eilidh Robertson told the court: “On January 19 2015, the accused attended at FTM Plant Hire in Cupar and rented a JCB digger and dumper for a week at a cost of £250.
“Upon completion of the hired week the items of machinery were not returned.
“The owner attempted to contact the accused on numerous occasions by telephone.
“He spoke to the accused on the phone several times, however, the accused kept giving excuses and eventually stopped answering the phone.
“The owner had a member of staff attend at the address the accused had provided when renting the machinery, but the member of staff was informed he no longer resided there.
“These items have never been recovered and their value is £21,000.
“On 26 January 2015, the accused attended at Gardens, Mowers and Tools Ltd in St Andrews and rented a mini digger for a period of one week at a cost of £280.
“He returned on 29 January 2015 and rented a further JCB digger, six buckets, a trailer and a ratchet strap for a period of one week at a cost of £250.
“At the end of the period, the accused failed to return the machinery and the police were contacted.
“The total value of the hired items from Gardens, Mowers and Tools was £38,000.
“Using the tracking devices fixed to the JCBs, the items were recovered by police, with the assistance of the owner.
“One JCB was found at a traveller’s site in Maud, near Peterhead and the other in an industrial estate in Kirkcaldy.
“A CCTV review was carried out at Gardens, Mowers and Tools Ltd, and the accused was identified as the person in the footage by police officers who had had previous dealings with the accused.
“On 24 February 2016, the owners of both companies attended an identity parade and identified the accused.
“The total value of the stolen items was £59,000, with £21,430 of that being uncovered.”
Stewart, 23, of Adamson Avenue, Kirkcaldy, pleaded guilty on indictment to two charges of theft.
Defence solicitor David Bell said: “He had a significant gambling addiction but has managed to put that behind him, primarily thanks to an ultimatum put to him by his partner.
“She is pregnant and due their child later this month.
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“It is a significant amount stolen and it is a very serious offence with a very significant value involved.”
Sheriff Tom Hughes jailed Stewart for a year, reduced from 15 months for his early guilty plea.
He said: “This was a deliberate attempt on more than one occasion to became involved in theft - and then to go out and sell these items on.
“The recovery of two of them in this case was good fortunate rather than anything else.
“It was a deliberate course of conduct and that makes it inevitable that a custodial sentence will be imposed.”
Stewart’s heavily pregnant partner wept as he was handcuffed and led to the cells.