To answer Chuck Rehor,
I bought a half dozen bottles of Carters stamp pad in made by Avery. My intention was to refill my bottle that has a brush. I do not recommend Carters. I will never buy it again. There is a hard plug in each bottle that takes about five minutes to dig out with a screwdriver.
Try some other brand of stamp pad ink. I have an old bottle with a brush on the cap. The label is so blackend with ink I no longer know the brand. Try to find at least one with the brush.

After I refill the bottle I squirt a little WD-40 into it and bush it on to about every third turn of the take-up ribbon spool. It is easy to get carried away and use too much. Then your printing gets so sloppy it is illegible. for a few passes of the ribbon. It takes trial and error. Of course you start just after the ribbon reverses and do the whole ribbon until it reverses again. I have found that much easier and neater than taking the spools off and inking the ribbon by hand.
Tom N3CRK