From: Campell, Marc [marcc@slac.stanford.edu]
Sent: Tuesday, June 21, 2005 9:03 PM
To: Mark E. Melton
Cc: Hascall, Patrick A
Subject: FW: Corner Radii on X-LAT
Mark,
 
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 closed.
 
 
RE:
Marc,
 
Have 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.
 
Mark

Marc Campell
Mechanical Systems Mgr.
(650) 926-4658

 


From: Herzberg, Scott Alan
Sent: Wednesday, June 09, 2004 9:36 AM
To: Campell, Marc; 'Wu, Sylvia'
Subject: FW: Corner Radii on X-LAT

FYI......


From: Opie, Michael V.
Sent: Wednesday, June 09, 2004 9:20 AM
To: 'Edinger, Derek'
Cc: Reynolds, Gary; McHugh, Stuart; Herzberg, Scott Alan; Ku, John
Subject: RE: Corner Radii on X-LAT

Derek,
 
Great! That sounds reasonable. I'll tell Scott Herzberg that he can keep the 0.125 radius.
 
Thanks a lot for the effort.
 
Mike


From: Edinger, Derek [mailto:derek.edinger@lmco.com]
Sent: Tuesday, June 08, 2004 6:57 PM
To: Opie, Michael V.
Cc: Reynolds, Gary; McHugh, Stuart
Subject: Corner Radii on X-LAT

Mike,
 
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 = 2.6). 
 
Based on these results, it's okay to keep the 0.125 inch radii in the corners.
 
Regards,
Derek