Kenny, the concave setting is a bit relative to the last time the pointer was zeroed in so a number one setting can have some varience. If you are getting all the lower grains thrashed out of the head you might try opening the concave a little.This will allow a little less straw damage to start with. Close the lower seive and turn up the air until you are blowing out grain.This is a situation where one of the fan deflecters really helps out.