This is from a PM1500 less than a year old. The PM1500 uses eight of these bearings, four top and four bottom. I use a 1/2 inch blade which makes contact with only the front bearings in the bearing holders. This bearing was completely seized. I thought it was from cutting green wood for bowl blanks. The water in the wood causing the bearing to rust. Does not look like it once I pried the shields off though. Packed with dust instead. The bearing has more dust caked on the side that faced the bandsaw operator than the oppposite side. The shields tell that story. This could be because the cleaner side of the bearing butts up against the back bearing in the setup. Less chance for dust to enter on that side.
I am wondering what would happen if I washed all the lubricant out of the new bearing and just ran the bearings dry. No grease to attract and hold the dust. The bearings are really cheap on Ebay. Around $1.25 each in quantities of 10, shipped. About five minutes to change the bearing. A thumb screw, a cap screw and a snap ring. So it really is not a big deal if I had to replace a bearing every month. I still wonder if running dry would prolong or shorten ?