Hi, All --
I have the frame removed for modification, tri-gear but could apply to
mono. There were about 10 hairline surface cracks, where the brass
bearings pivot around the lower member, each side. Using a hobby file
set (i.e., small and fine) and magnification, it is clear they are all
at the surface, no more than .002" deep. They all run 45-deg to the
steel member, 1-3mm long, parallel to each other. Thus it is clearly
not mechanical damage. A/C has had engine mounted, but not flown. I
dressed them all out under magnification, finishing with emery cloth.
I guess that's OK; very little metal removed, but I was concerned over
stress concentration (i.e., real serious cracks later).
Has anyone seen this? Is it stress from welding (I swear they weren't
there prior to engine hanging) that the 914 relieved??? The affected
area is between where there are many welds for straps and vertical
members.
Regards,
Fred F., A063
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