This is sort of off-topic, but I recently began to realize that the Richeson brush size needs to be matched with the print size to some degree. I was coating some 4x6 test wedge prints with a 3" brush, and the resulting prints were really weak and had abnormally low Dmax. I thought I was experiencing some sort of solution 'failure' until I realized that the volume of water still contained in the brush was completely diluting the smaller-than-normal volume of coating solution I was using for this small print (about .3mlFO/.3mlPd). When I switched to the 1-1/2 inch brush, the problem was solved. So the moral is: you can use a smaller brush on a bigger print, but you can't use a bigger brush on a smaller print.