Your chopper should have a round bar that is used to hold the plates above the knives in place. That bar also is a gauge to set the first two outside knives on the drum. After you set them then you need to adjust shearbar to those two knives. Then every knife after that is set to shearbar. Keep in mind some Kooima shearbars were built wider, so when you do back the shearbar up to adjust the clearance on the two guide knives, sometimes it will push the scraper into the smooth roll. You want the smooth roll to turn pretty easy and so you dont want the scraper putting a bind on it. We had trouble with Kooima shearbars and knives in the past when we ran 6000 series. They have a good shearbar now for the 7000 wide body machines that is very durable, but like cptusa says the knives are good for scrap. Also I read where you were noticing that the drum was closer on one side than the other, maybe check your cutterhead bearings. Hope this helps, good luck!