Militch@aol.com wrote:

Dale Smith wrote:

A long time ago, I seem to remember reading that glass bead blasting was
recommended to race prep connecting rods and "relieve internal stresses".

Is this

true?  or just another "hype"?

If true, it would be a plus in it's favor, but then again, the rotors don't

fail

anyway, right?

Dale Smith

I am not sure they use glass beads for that. Some sort >of blasting medium
is used to increase the fatigue life of metals. As I >recall it is called
shot peening.

Shot peening is indeed used to toughen some metal parts.  The steel shot hits the part at high speed and work-hardens the metal.  I believe the effect is something like the pre-stressing you get on plate glass.

Regarding glass beading - it works beautifully on aluminum parts and gives a very nice buff finish that doesn't hold oil stains.  Beware of doing any part that the inside of the engine will see. I know of one case where someone glass beaded an inlet manifold, and even after rigorous washing, still experienced some severe engine damage once they put the part into service.  Those beads get everywhere.  If you do this, it's best to tape off all galleries or ports - any orifice that might hide beads and allow them to find their way into the engine once it's operational.

Regards

 
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