Roy Thompson, son Matthew and grandson Christopher Baxby all had the liquid squirted in their faces during the raid on the business premises.
A gang of five burst into Wakefield Off Road Motorcyles, on Thornes Lane, Wakefield, on September 17 this year as they were about to close for the evening.
One member of the gang, Cori Braham, 31, was jailed for eight years over his role in the robbery.
Braham and a 16-year-old attacker were carrying bottles filled with ammonia which they squirted at the victims.
Another man swung an axe before they left with a motorbike worth £2,000.
All three victims suffered facial burns from the liquid but managed to fight back.
After the case, Mr Thompson said it was the THIRTIETH time his premises had been targeted since he opened the business in 1986.
On a previous raid robbers beat him unconscious and threatened to chop his hands off.
Speaking to the YEP after the case, he said: “I am not happy with the length of the sentence given to this man. It should have been much longer.
“I think the criminal justice system has forgot the meaning of the word justice.”
The 65-year-old read a victim statement to the court in which he described the terror at having liquid thrown in his face.
He said: “The sight of five assailants clad in balaclavas and armed, squirting liquid which could have been acid or anything is as terrorising as any ISIS bomb and has the same permanent effect.”
The court heard that all three victims had been on medication to cope with the trauma of the robbery.
Braham, of Kepple Close, Doncaster, was jailed for eight years after pleaded guilty to robbery and threatening a person with an offensive weapon.
A 16-year-old defendant, who cannot be identified, was given a two-year detention and training order after admitting the same offences.
Braham and the teenager sped through rush hour traffic on the stolen bike but were caught after the West Yorkshire Police helicopter was deployed.
The pair were found hiding in a tree in a field in Ackworth.
The three other robbers managed to escape in a car after the incident.