The os 28 doesnt have a tight pinch. Ive had 3 of them and all have been easy to break using a crappy old thunder tiger box. They only take half a gal to break in and mine starts 1st go every time. Its the easiest mill ive broken in. The first 2 i didnt even pre heat to break in. The 3rd 1 i heated with a hair dryer and losened the plug. Easy as!
Lean out the high speed half a turn.