Posted for "George/Shirley Shattuck" <kloop@plantationcable.net>:

 My manual (1989 kit) called for that curve in the door so I built a curve in
 with glass and heat.  I have also always put a foam sealer on the fuselage
 edges for the door which the door closes on.  It is just the 1/4" stuff you
 buy at the hardware store.  It is sealed tightly and there is no buzz.
 
 Shattuck
 N320GS
 

"""
 I wonder if your problem is not with the hydraulics at all and is the door
 itself.  There has been a long history of people having buzzing noises
 coming from their nose gear doors at higher speeds.  The problem in this
 case has been that the belly is slightly curved (front to rear) but the door
 itself tends to be straight.
"""