We have seen some machines were oil has built up and then gotten some very nice fabric, very messy. We are suggesting that you DO NOT oil the 7 series machines (710, 720, 740, 750, 770, 780, 790) and the New Generation 5 series (500, 535, 570NG, 590E) with the red dot under the needle plate but rather by removing the hook itself and oiling the rim of the hook just like our classic Bernina machines. This is different from the information in your manual, but it will keep your machine oiled just as well without the possibility of oil getting on your projects. Here is a video from Heirloom Creations showing how to clean and oil the B Hook System. This is advice goes for all machines that use the large black bobbins with reflectors that are not 8 series machines.