Staff were given the news at a meeting at 7am on Tuesday, when they were handed a list of those who would keep their jobs and those who would have to go, one worker said.
It is understood the 11 redundant workers finished yesterday, although calls to the foundry's office were not answered.
Bradken mining and transport group executive general manager Bradley Ward, speaking from Australia, said the redundancies were the result of a continuing downturn for the company and its customers.
Bradken Dunedin supplied products for the rail, forestry, heavy engineering and manufacturing industries, but the market continued to be ''very soft''.
It had been hoped last month's move to a four-day week for the Hillside Rd foundry's 74 staff would be temporary, allowing them all to ride out the tough times, but Mr Ward said yesterday that had not worked.
''Even at the four-day week, we've got insufficient work to have retained all of the people. To keep the operation viable, we've had to let some go.
''We need to make sure that we remain viable and keep our businesses going through the downturn, so that we can participate when things turn.''
Mr Ward, asked last month about the potential for job losses, dismissed the need to take ''other action'' as ''pure speculation''.
''We're not expecting to have to do that,'' Mr Ward said.
Yesterday, he could give no guarantee further job losses, or a complete closure, would not be needed.
''We have no plans to close the foundry and we would expect the end markets to stabilise, but I can't predict the future any better than anyone else.
''We're reacting to the markets as things evolve. If they pick up and we can put people back, that would be wonderful. If markets remain soft, I guess times remain difficult for us.''
In the meantime, the four-day week would remain indefinitely for the 63 staff who remained at the foundry, he said.
''The decision we took around the resizing was based around the amount of work we have at the four-day week. The amount of work we have now is good for the four-day week with the new staff level.
''We'll have to assess things as time goes on.''
News of Bradken Dunedin's redundancies came two years after it took over the Hillside foundry on a five-year lease from KiwiRail, as part of a push to expand its operations.
Amalgamated Workers Union New Zealand (Southern) secretary Calvin Fisher said the job losses were ''a real tragedy'', but also the continuation of a trend in Dunedin.
''This is just a reflection of where manufacturing and the blue collar trades are at.''
Those losing their jobs were ''very skilled'' and would find it hard to secure similar work in Dunedin, he believed.
Dunedin Mayor Dave Cull said the job losses were part of a ''really worrying trend'' following last month's news Esco Dunedin planned to close its foundry by the end of the year, with the loss of 34 jobs.
''It shows you how global ... trends can impact right down to jobs in our own city,'' he said yesterday.
