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Old October 21st, 2019, 04:35 PM   #15
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T CBR250R-MC19 CBR250RR-MC22 NSR350R-MC21 VF500F CBR600RR SFV650 VFR750F R1M ST1300PA Valkyrie-F6C

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
All stronger epoxies tend to be hard with fracture type failures. That's OK as force required to break them is 2-3x higher than softer more pliable ones. Adding some irregular aggregate material such as steel filings or chopped fibreglass greatly improves strength and breaks up 'grain' boundaries, making it more crack resistant. Think of difference between cement vs. concrete.

Design looks OK, I think failure was due to process breakdown. Proper surface-prep was not done on flat bar-stock. Or some bean-countre changes were made after initial design was completed. Such as changing from cold-rolled stock to hot-rolled or galvanized. All of which would require changing surface-prep operation before welding.

I think I'm going make my own rack. Just waiting for my top-box to arrive and will customise rack just for it. You can come over and i'll show you how to braze joints on your rack. Here's Renntec rack for different bike that also failed. Solution was welding reinforcement.


Last futzed with by DannoXYZ; October 21st, 2019 at 09:52 PM.
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