In a message dated 9/20/99 11:31:10 PM Pacific Daylight Time,
monadnoc@crystal-mtn.com writes:
<<
>
> Brings up a question, in your opinion, how well do the flux kits sold
from
> Napa work? I've used them in the past to check for cracks between exhaust
> seats, and assumed I was getting my money's worth.
>
> Mike
Mike, I'm not familiar with the Napa kit, but I did notice that Eastwood
sold a
kit of liquid penetrant materials, where you spray or paint on the penetrant,
let it soak a bit, wipe off the excess, and then spray on a white powder
developer that shows the crack location. If that's similar to the Napa kit,
let
me know. These type of do-it-yourself crack finders work pretty well. The
secret is good cleaning before using the penetrating material, and then good
cleaning of the excess. The dye will stay in the crack and leak out via
capillary action. But insufficient cleaning off the rest of the surface will
result in poor visibility due to there still being excess dye on the surface
surrounding the crack.
The other type of test that machine shops perform (the one I referred to in
the
last post) is that of magnetizing the offending area with a magnet and while
it
is under the magnetic field, an iron oxide powder is dusted on. It sticks to
the edges of the cracks, similar to the way iron filings cling to the edges
of a
magnet.
Sometimes the 2 tests are confused due to the fact that Magnaflux Corporation
makes materials for both types of tests!
Wally >>
Thanks for th info wally, I'll have to read up on the Eastwood kits and
see if they're the same as the one I got from NAPA. Probably are, just
different packaging.
Also, I didn't know "Magnaflux" was a company, I thought it was a process.
Just when I thought I knew everything......
Mike
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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