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<DIV>Jon,</DIV>
<DIV> </DIV>
<DIV>The problem with the aluminum being heated and cooled every time</DIV>
<DIV>you run the engine acts like an artificial aging (hardening). In time the
</DIV>
<DIV>material will get very brittle and therefore break very easy. Here is a
little</DIV>
<DIV>trick you can try that I know works: If you have a self cleaning electric
oven</DIV>
<DIV>at home, put the header in the oven run the cleaning cycle. Do that at
night</DIV>
<DIV>before you go to bed and the next morning you header will be
annealed.</DIV>
<DIV>It has to cool of slowly.This is the opposite process of hardening. This
makes</DIV>
<DIV>the aluminum more flexible and less prone to breakage.</DIV>
<DIV> </DIV>
<DIV>Karl G. Mueller<BR><A
href="mailto:kgamueller@rogers.com">kgamueller@rogers.com</A><BR></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=JonLowe@aol.com href="mailto:JonLowe@aol.com">JonLowe@aol.com</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, September 07, 2005 8:39
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Bulk] Heat treating aluminum
header?</DIV>
<DIV><BR></DIV>
<DIV>After many many flights, I had an aluminum header break for my OS
1.60. I had it welded up by a very good welder, but the header broke
again after one flight in an area removed from the weld, but close enough that
it would have gotten pretty hot. I suspect that the heat treat of the
header got changed. Any ideas on how to try to heat treat a second
pipe that has benn welded to try to at least get more than one flight?
I've odered a new header, but it is not here yet.</DIV>
<DIV> </DIV>
<DIV>Thanks</DIV>
<DIV> </DIV>
<DIV><FONT size=2 PTSIZE="10">Jon
Lowe<BR></FONT></DIV></BLOCKQUOTE></BODY></HTML>