I am dethatching my lawn for the first time.  I have a front mount dethatcher on my tractor.   How much should it dig into the grass?  I set it up so that on a level service in the garage so the tine's are 1/2 - 3/4 quarters of an inch off the ground.  When I used  it (on a small area) there seemed to be more pressure on the tines then I expected,   and it left 'streaks'  in the lawn where it dug up everything including the grass and left bare dirt.  Is this normal?
	
		
			
		
		
	
			
			 
				 
 
		