Warp Drive Cracking
Posted: Fri Feb 17, 2012 8:34 pm
Wayne & Bob, Thanks for your comments.
Talked with Daryl and he says the problem is with the higher horsepower
engines when at low RPM'S. In my case the cracking occurred in the
aluminum clamping sleeve, close to the outer edge of the hub and ran
around the blade versus the 160 HP cracks which Daryl said usually
started there but then progressed up the blade into the carbon fibre. At
some points the cracks looked like corrosion pits but mostly was a fine
line crack with no deformation which scotchbriting seemed to hide. In
one spot there was enough deformation to actually catch my finger nail
however.
His recommended solution is to add a harmonic dampener which I believe
was mentioned in the meeting although I can't remember what was said. He
is not concerned with an imminent prop failure but the cracks could lead
to unwanted vibrations. He will be sending replacement blades at the end
of the week and I'm awaiting a call back from Mark Landoll re the
purchase of a dampener.
Ron
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Talked with Daryl and he says the problem is with the higher horsepower
engines when at low RPM'S. In my case the cracking occurred in the
aluminum clamping sleeve, close to the outer edge of the hub and ran
around the blade versus the 160 HP cracks which Daryl said usually
started there but then progressed up the blade into the carbon fibre. At
some points the cracks looked like corrosion pits but mostly was a fine
line crack with no deformation which scotchbriting seemed to hide. In
one spot there was enough deformation to actually catch my finger nail
however.
His recommended solution is to add a harmonic dampener which I believe
was mentioned in the meeting although I can't remember what was said. He
is not concerned with an imminent prop failure but the cracks could lead
to unwanted vibrations. He will be sending replacement blades at the end
of the week and I'm awaiting a call back from Mark Landoll re the
purchase of a dampener.
Ron
*-----------------------------------------------------------------------------------*
The Flying Rebels List is for the discussion between
builders and owners of complete/flying Murphy Rebel
aircraft. Archives located at:
http://www.dcsol.com/murphy-rebel/lists/default.htm
*-----------------------------------------------------------------------------------*
-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
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