Shot Peening

[rob w]

Has anyone ever had the shot peening process done to their connecting rod? Sounds like it would be a wise think to do after hearing stories about the modified Sachs engines eventually blowing. Thanks, Rob


 

[Frank]

I have not used this process on Penton parts but I can give you the lowdown on what shot peening does,
On the surface of any piece of material there are slight imperfections known as stress risers. when a failure occures the crack always starts at a stress riser. Peening or polishing the component reduces or eliminates the stress risers sothere is no place for the crack to start. Peening goes one step further by actually compressing the surface slightly in addition to making it smooth.
You would want to have a magnetic particle inspection process done (most race car guys do this) (magna-flux) and make a metal "fixture" to protect the bearing surfaces from damage during the peening process. there are also cryogenic process that are touted to increase strength but without alloy information I would avoid these processes.  Peening helps reduce catastrophic failure (breakage) and perhaps post peen polishing the leading and trailing edges of the rod may help too..