Maxwell Taylor surrendered to police the following day still wearing the clothes he wore for the crime, which were covered in dye from a special “raid pack” he was given along with £20.
Taylor, 29, who previously lost part of a lower leg after it was blown off by an electric current, told officers: “I knew I’d be caught eventually so I thought I’d hand myself in.”
He revealed that after robbing the bank in George Street he fled to a hotel in Perth and added: “All part of my great escape plan.”
Taylor, described as a prisoner, admitted assaulting NatWest Bank employee Sahir Hiqqash and handing over a note saying he was in possession of a bomb which he would detonate unless he was given money, and robbing him of £1670 on June 27 this year.
The High Court in Edinburgh heard that he walked into the branch carrying a rucksack and queued up to wait his turn at the counter.
When he arrived at the counter he slipped a note to Mr Hiqqash stating: “I’ve got a bomb in my bag, hand over the money or you go bye bye.”
Advocate depute Hugh Irwin said: “The victim thought the accused was joking until the accused pushed the rucksack towards him.”
Mr Hiqqash alerted another a colleague by using a code word, and they watched as he handed over banknotes along with the raid pack which activates when it is taken out of the premises, spraying pink dye.
Taylor, who was living in a homeless hostel at the time, fled the premises with the cash and police were alerted.
CCTV footage revealed that after he left the bank he boarded a bus bound for Kirkcaldy in Fife. The bus was traced but by the time police arrived he had left.
The following morning, however, Taylor turned up at Perth police station and asked whether he could hand himself in for a robbery in Edinburgh.
He had a bundle of money which he said had come from the bank. He said he had got a train and stayed at the Station Hotel.
He was asked if he had a hidden weapon and said: “No, but I’m wearing the same clothes. Look, they’re covered in the bank dye.”
Police recovered £800 from Taylor and found £140 covered in pink dye in the hotel cash box.
Mr Irwin said that the robber was interviewed and gave “a full and frank admission to the crime”.
He said: “I wasn’t obviously going to blow anybody up.”
Defence solicitor advocate Krista Johnston said that last year Taylor had an accident and part of his leg was blown off by an electric current. She said that at the time of the offence he had no money and that was his motivation.
The judge, Lord Turnbull, deferred sentence on Taylor for the preparation of a background report until next month and remanded him in custody.