From: Campell, Marc [firstname.lastname@example.org]
Tuesday, June 21, 2005 9:03 PM
To: Mark E. Melton
Hascall, Patrick A
Subject: FW: Corner Radii on X-LAT
I found this embarrassingly old email that closed the
issue. I did take a while for Spectrum to agree & then to update the 00040,
which now reflects the .125" (3.18mm) radius below. So yes this is
you verified that the recent 00040 drawing updated closed the issue raised in
X-LAT MRR RFA #2. I'm waiting for confirmation of this from you before I
officially close it.
Mechanical Systems Mgr.
Great! That sounds reasonable. I'll tell Scott Herzberg
that he can keep the 0.125 radius.
Thanks a lot for the effort.
I checked my
original, detailed X-LAT model with the nominal corner radius of 0.125 inch and
got 13 ksi from the offset case plus 7 ksi from MECO which results in a MS on
ultimate of -0.2 (with a qual-by-analysis SF = 2.6).
When I added shear
springs to the edge fasteners, it didn't have much affect on the stresses
(around 1% reduction). After looking at the deformed shape I realized most
of the stresses come from plate bending due from the offset case which is
relatively unaffected by the joint shear stiffness. However, when I added
axial springs, the stresses dropped significantly. I calculated an axial
stiffness of 2.7E6 lb/in for the clamped joint from Shigley. With this
spring stiffness in the model, I got 2 ksi from the offset case plus 3 ksi
from MECO which results in a MS on ultimate of 2.7 (with a qual-by-analysis SF =
Based on these
results, it's okay to keep the 0.125 inch radii in the