NEWBIE ???: stroke weights on Paintbrush tool

HI all,

I'm having trouble with my paintbrush tool. I'm drawing my picture with the paintbrush tool using the thick to thin brush from the palette in 1pt. When I want to add more detail and use a smaller stroke (.25), I try to change it in the stoke window but when I go to brush something on, it reverts back to 1pt. What am I doing wrong? How can I adjust stroke weights on the fly when I use the paintbrush and or pencil tool? Any help is appreciated.


Thanks,

Buddy