if i read this post right your trying to thin with windex? your using the wrong thing to thin your paint you use windex to clean between colors not to thin the paint look up reducer on here for homemade reducer or buy some at the store,also if your using folkart paint from the craft store i reduce it 60/40 with distilled water and shake it really well then run it thru a paint strainer(you can get them at home depo,ace about any store that sells paint by the gal.)that gets rid of all the larger paint chips so it will shoot better thru the brush hope this helps