Main Bearing Bore Line Honing

is the line home so this is what's going to establish the center line of the main so the block will go in this machine upside down and we will hone all of the main housing bores at one time with this mandrel so a brand new block um we will cut the caps as well as a used block so i talked to you about earlier in the other video uh cutting the caps this is here your cap grinder so the the main cap will go into this into this grinder it'll clamp down and we'll able to actually grind the surface of the cap to make the housing bore smaller um that's cool i've never seen one of these before that's some that's stuff like some serious industry what's the vintage on this stuff i know the best stuff is always like yeah so this one i don't this one is actually probably from the fire to guests probably from the late 70s or 80s if i were to guess the red the red all the sunning gurus might know what this one is but yeah it works well they used to have a uh an old stone but this is a kind of the new technology is using a cbn material um so a lot harder you don't have to dress it and stay super uh super flat and creates a really nice surface finish so once we've cut those main caps we'll get it in here we're able to we're able to get our housing boards round and straight four decimal places out so the distance between zero and one each one of those is a tenth which is point zero zero zero one of of an inch and we're looking for to have the housing boards absolutely as round and straight as possible so when we're in the assembly room and we're checking our bearing clearances we have consistency from one to the other as well as having the journals in line with each other so there's no distortion that way so uh that's crucial this is kind of the foundation of the entire process is the line hone you know when you talk about blueprinting a block it's not only doing all the the different operations but it's the order of operations which is extremely important so everything starts with the line home if you think of a blueprint and an engine you have the center line the main out to the deck surface the center line of the main out to the other