He threw the cat's milk and saucer at the nearest youth but the other three set upon him. As he was on the ground being kicked he was able to reach a shovel, which he used to strike one of his attackers on the head. They then fled.
Mr Bradshaw said the youths were in their mid to late teens and not local because he didn't recognise any of them. There was nothing in the workshop of value to anyone else, he said.
The attack and attempted burglary was disappointing but his main concern was that it could put off new volunteers.
Mr Davis said the trust felt "absolute abhorrence and disgust" over the attack which could have severely injured the railway's long-serving operations manager.
He urged anyone who knew the attackers to call the police so they could be held to account. One would have a new facial scar where he had been struck with the shovel.
"Someone will know who these scum are," he said.
Mr Bradshaw had been instrumental in getting Kawakawa's trains running again, was a key member of the trust and "totally committed" to restoring the railway for the community's benefit.
If anyone wanted to support Mr Bradshaw or the railway, the best way to do so was by becoming a volunteer.
Far North Mayor John Carter, a long-time railway supporter, described the attack as "scandalous".
"The whole community should be absolutely outraged. I hope that someone who knows who they are has the decency to front up."
Mr Carter said grandmothers and aunties had reported their own family members after a recent incident in Kaikohe, and he hoped to see the same happen in Kawakawa.
Mr Davis said the bashing came just three weeks after the theft of a model train used as a donation box, making him question how bad crime in the North had become.
The recent announcement of 66 new frontline police in Northland over the next four years had brought real relief in Kawakawa which, like many other areas, suffered a "severe shortage" of police.
Mr Bradshaw is a world authority on vintage rail. In Wales he oversaw the rebuilding of 12 steam locomotives, six diesel engines and 100 carriages of the Ffestiniog and Welsh Highland Railways. He has also worked on railway restoration projects in Argentina and Vietnam.
In 2011 he received the Federation of Rail Organisations of New Zealand's top honour, the PS Heighton Award for Excellence, for his contribution to the nation's rail heritage.
■ Police urge anyone who knows who the youths are to call the Kerikeri station on (09) 407 9211 or Crimestoppers, anonymously, on 0800 555 111.
