The National High Magnetic Field Laboratory (NHMFL) is building a 25 T, 52
mm bore resistive magnet with field uniformity and stability of 1 ppm over
a 1 cm diameter spherical volume (DSV). Upon completion the unshimmed magne
t's homogeneity was 48 ppm over 1 cm DSV. It has since been ferro-shimmed t
o 12 ppm over 1 cm DSV and we are in the process of shimming to the 1 ppm l
evel. Details of the design, construction, shimming and stabilizing are pre
sented.