The Rail, Maritime and Transport (RMT) union has escalated a long-running dispute by signallers in Stirling over their rosters after a series of two-day strikes failed to win any concessions from Network Rail.
The announcement comes weeks after the union called off a series of strikes by ScotRail staff that threatened to cause transport chaos on the last Saturday before Christmas and on Christmas Eve in a dispute over a sacked ticket inspector.
The Stirling signallers want to work a three-day week instead of five, but extend their shifts to 12 hours so their overall working hours remain the same.
Network Rail, the company responsible for the UK's track and signalling infrastructure, said the request was unprompted and would add a further £40,000 a year to the cost of the signalling system.
The escalation comes after the failure of talks held through the Advisory, Conciliation and Arbitration Service.
While previous strikes have not had any impact on services, managers fear a national dispute would have a bigger impact.
A strike by signallers in 2009 led to cuts in frequency and cancellation of some early morning and late evening services.
The union also said its signalling members in Stirling would launch another 24-hour strike on Saturday.
RMT general secretary Bob Crow said: "Despite the RMT making every possible effort to resolve this dispute through negotiation we have met with nothing but a brick wall and broken promises.
"We now have no option but to move to a strike ballot across Scotland."
The union says Network Rail is in breach of agreements giving it the right to negotiate shifts of between six and 12 hours and that a verbal agreement this would be granted if staff wanted it has been broken.
But the claims were rejected by Network Rail, whose spokesman insisted no agreement to change the shift patterns had been given.
He said: "Meeting the union's demand that signallers begin to work fewer days each week would mean operating a less efficient and more expensive railway.
"We have made every effort to resolve this dispute, including the involvement of ACAS. We have conducted detailed analysis of shift patterns, but cannot see how they can be changed without increasing operating costs by around £40,000 a year.
"Compromises offered, including 12-hour weekend shifts, have been rejected unilaterally by RMT without explanation. We remain committed to resolving this dispute and further talks are planned, but we are disappointed the union is trying to force this through with the threat of strike action.
"At a time of economic restraint, we should be seeking to further reduce the costs of the rail network to the fare-paying public and taxpayers."
The Confederation for British Industry Scotland called for a resolution to be struck.
Lauren Paterson, its senior policy executive, said: "At a time of fragile economic recovery, which relies on accessible and available transport options for passengers and for freight, we would encourage a speedy resolution and would urge the unions to get round the negotiating table with Network Rail and talk until they get a result that satisfies both parties."
A ScotRail spokesman said: "This is a matter for Network Rail and the RMT, and it is hoped the dispute will be resolved."