RF Cavity for Synchrotron Storage Ring, Indus-1, is made of Stainless Steel and it is internally electroplated with copper. The cavity is having an internal diameter of 840 mm and length of 600 mm. The cavity structure is re-entrant type and there are big “capacitor disks” at 10 mm from the median plane which are attached to the end plates through 250 mm long “drift tubes”. Vacuum in the RF Cavity for Synchrotron Storage Ring, Indus-1, started deteriorating in the month of June 2001 and within few weeks time the vacuum level deteriorated by 3 orders. The leak check, which became quite complicated due to the location & internal electroplated surfaces, showed a leak in the drift tube. Work was done to analyze the problem, design of alternative structure & the cooling circuit, FEM analysis of temperatures & thermal deformations, tuning, manufacturing, electroplating, assembly, vacuum testing, RF testing and integration in the ring for operation. All the work of design and manufacturing was completed in two months time. The cavity is now working in the ring with a vacuum level of 1 x 10-8 mbar. The total thermal detuning is now less that 50 kHz at 22 kV, which is well within the on-line tuner range (80 kHz), and start-up time is about 10 minutes.