RPM the A&P wrote:

Thank you for your recommendations.

Agreed. I would love to replace the boom and I have tried to do so for some
months now. Regrettably, they no longer appear to be in production. FWIW,
the original listed in the Coot bill of materials was a
Reynolds-manufactured irrigation pipe.

A number of aluminum distributers have informed me that there are no drawn
tubes in this diameter and wall thickness, or anything close to it,
currently available from any manufacturing source.

Additionally, the rolled and welded tubes that I have located are
unacceptable due fabrication quality, alloy, or both. In fact, I purchased
one tube sight unseen from a former Coot builder, but it turned up with such
extreme tooling (roller) and welding marks that I have reassigned it to
become a pair of reflecting telescope bodies and nothing more. Fortunately,
it only cost me $20. :-)

Finally, after contacting all the folks that I have been able to find in
North America who have been know to have spare Coot components, I've still
failed to turn up an acceptable replacement.

Fortunately, although this boom will be enclosed in a tail fairing, the
repaired area can be made highly inspectable.
For now, I am still planning to pursue a repair.

However, based on your recommendation, let me expand the scope of this
request...

If anyone on the group is aware of a source of drawn tubing that's 116 inch
long, 10in OD, ~.063in wall thickness, and that's made out of 6061-T6,
6063-T3, or 5051-T3, I'd love to hear about it.

Thanks!

Russ



It might be more productive to ask the composite guys about how to make
a glass copy...