The new notes were billed as being hi-tech and durable and were said to last twice as long as the old fiver.
But a print centre manager who experimented with one of the bills found it can be wiped almost totally clean of ink with an eraser.
Stuart McLean put the bill to the test using the type of rubber normally deployed to eradicate pencil marks.
To his surprise the everyday item was capable of scoring off large parts of the note’s blue dye, leaving only security numbers and the see-through hologram behind.
The polymer note, which has been issued by Royal Bank of Scotland, Clydesdale Bank, Bank of Scotland and the Bank of England, is smaller than traditional fivers and said to last 2.5 times longer.
Banknote manufacturer De La Rue say it can survive a spin in a washing machine without losing its colour.
But Mr McLean said that it could not stand up to an abrasive surface.
He said: “I used a pencil eraser to rub it out and found that the ink underneath rubbed away as well.
“I kept going and was able to turn one side completely white.”
Mr McLean, who works in Cambuslang, Lanarkshire, performed the experiment on a Clydesdale plastic note, which features an image of the Forth Bridge.
It was issued to commemorate the bridge’s 125th anniversary and a portrait of Sir William Arrol.
However, he was also able to reproduce the effect on Bank of England note, rubbing out the world ‘England’ to prove the banknote’s vulnerability to a colleague.
A spokesman for De La Rue said that notes would not normally lose their ink, and insisted that Mr McLean’s had been subjected to “excessive and abnormal ink wear.”
He added: “Whilst ink wear is the ultimate failure mode of polymer banknotes in circulation, the ink wear displayed here appears to us to have been achieved by a method not representative of what happens to a banknote under normal circulation conditions.”