Painters have been working on the bridge for more than a century
The owners of the Forth Bridge are hopeful work to paint the structure will be completed a year ahead of schedule in 2011.
New techniques and products are being hailed for the success of the project, which began in 2002.
Special paint is being used which should last up to 30 years - meaning that the railway bridge will no longer need to be painted continuously.
Work on the iconic structure is already ahead of schedule.
The completion date is still officially 2012, but Network Rail - which owns the bridge - said it was confident it would be completed "well before then".
A 200-strong team is applying a triple layer of new "glass flake epoxy" paint, which is similar to that used in the offshore oil industry.
It creates a chemical bond to provide a virtually impenetrable layer to protect the bridge's steel work from the weather.
The need for continuous maintenance of the structure has passed into folklore and led to the coining of a phrase for a never-ending job.
Forth Rail Bridge
The bridge was built between 1883 and 1890 and is 1.5 miles long
The track is about 150ft above the water level and the bridge reaches 330ft at the tops of the towers
It is a steel structure and contains more than 6.5million rivets
The expression "like painting the Forth Bridge" features in the Cambridge International Dictionary of Idioms.
It states: "If repairing or improving something is like painting the Forth Bridge, it takes such a long time that by the time you have finished doing it, you have to start again."
For more than 100 years, that is how painting work on the bridge has been carried out.
However, now the work involves screening off sections of the bridge before old paintwork is removed and any repairs carried out on the bare steel.
The new paint, similar to that used in the offshore oil industry, is then applied in three coats.
A spokesman for Network Rail said: "2011 is now the preferred date and things are moving towards completing the job then.
"We have been gradually moving ahead of schedule since the project started in 2002.
"We have got more work completed than originally forecast, because we are no longer going through a learning process."