Re: Help! Dealer woes . . .

[esw5@postoffice2.mail.cornell.edu (Ernest Wong)]

from Dan Bocek:
[stuff deleted] 
>Well, the head is off at a shop now specializing in repairing terminal
>head damage.  What they're going to do is heliarc weld blobs of
>aluminum into the chingered parts of the lifter bores, and then re-
>machine the whole thing. They said that when they're done, I wouldn't
>be able to tell that there was ever any damage
>
In the welding course I took, the teacher showed us and told us that a
well-made joint is stronger than the metal it joins. He soldered an unbent
paper-clip with a match and 60/40 household solder. He then let one of us
break it. The paper-clip broke but the joint held. In later excercises, to
visually check the quality of our joints, we had to quench the joint to
make it fragile before we can break the metal at the joint. Even our
amateur welds would have held tight if we did not weaken it.

>Here's another interesting tidbit: of course I'm replacing all of the
>valve springs, but how do I know one won't break on me again in the
>future?  John at Sport Wheels suggested that we have the springs
>'magnafluxed' to check for any initial stress in the metal.  Anyone
>know anything about this?
>-- 
Isn't 'magna-fluxing' checking the metal with a probe that emits a magnetic
field? Any imperfections (micro-fracture) under the surface of the metal
will cause the magnetic field to change alerting the tester to possible
flaw in the metal there. Think that is what they use to test the rivets
holding the aluminum panels on passenger jets. Expensive job since there
are so many rivets on a big airliner. 

Ernest Wong
esw5@cornell.edu