I think the back teeth do next to nothing. I stick teeth the teeth in those positions that have been re-sharpened, but have the least amount of carbide left. If I have a tooth with a big chunk of carbide gone, I'll run it there to get more hours out of it. I never feel like I'm spending money to fill those positions, I'm just squeezing more life out of teeth who are not worthy to be in the # 1 and 2 positions. I'll never use a dull tooth in any position. When I wire wheel the pile of teeth I've taken off, I grade them 1,2,3 or 4. Line them up in rows according to their grade. When I do a full 24 teeth change out, I grab the next 6 in each line and go to it. I probably wear out 4-6 sets at the #1 position before I change the 3 or 4 position. That includes rotating once. So, yeah, 10 to 1 or 12 to 1. But, then that one gets rotated... 20 to 1, 24 to 1. I have a couple hundred teeth. All different stages of life. If I have a good supply of 3s and 4s, more worn teeth go to the box that will be re-tipped. When I have 67 good teeth in the board ready to sharpen, off to Jeff's Sharpening they go. The trick is to never run out of #1s... I carry 14 #1s in the truck. If I feel like I'm using too much horsepower, or get into a mess of pines, I stop and change the 6 at #1 position with clean sharp teeth. Don't even look to see if the takeoffs have another edge. Clean them up and grade them on a rain day. It's just like a chainsaw... gotta keep it sharp. Whatever time you spend keeping it sharp is repaid in productivity.
