Overhaul 14 year old prop?

Yes, bare aluminum is porous, the anodizing 'seals' it.
"nrp" wrote in message
oups.com...
Some random points on props:


A Mil Spec manual somewhere showed that anodizing reduces the fatigue
strength of aluminums about as much as shot peening can increase it.
They must do anodizing for other reasons - maybe to provide some
corrosion resistance?

On 26 Sep 2005 18:14:12 -0700, "nrp" wrote:

Some random points on props:

A prop is highly stressed and will grow in diameter almost 1/8 inch at
takeoff due to centrifugal forces - whether steel, aluminum, or wood.
(Does that get your attention?)

Indeed, especially when standing a little bit in front and a little
bit to the side of a 600 horse R-1340 or PT6A running at cruise rpm
with a C-H Strobex in my greasy mitts. Had an turbine Air Tractor
climb the chocks once-guy driving it was a sharp cookie-had the
throttle back before it came down the front side of the chocks...

I understand it takes an A&P signoff just to paint or touch up a prop -
even on the black backside.

I wasn't around when standard terminology was defined, but the "back"
of a propeller blade is the cambered side-typically painted with white
tips and a mfg's decal, and the "face" of a prop is the relatively
flat (and matte/flat black) side that "faces" you when you sit in the
driver's seat of a typical single with a tractor-type prop.

A Mil Spec manual somewhere showed that anodizing reduces the fatigue
strength of aluminums about as much as shot peening can increase it.
They must do anodizing for other reasons - maybe to provide some
corrosion resistance?

Yup. Been too many years, but am thinking that Sensenich fixed-pitch
and older Brand M blades get grey-anodized. The local prop shop had a
way-cool "T"-shaped anodizing tank made. Fixed pitch props were hung
in the solution of the bus bar horizontally, the c-speed blades
vertically.

From personal experience, the right prop guerrillas can do a remarkable
job getting a prop to run right - at least fixed pitch ones.

Agreed.

TC

"karl gruber" wrote in message
oups.com...
Why anyone would want to cut corners on prop
overhauls and maintenance on the basis of statements such as "guerrilla
eye"
is beyond me.

Juan, most aviation related topics ARE beyond you comprehension. Glad
you finally recognised that. Why don't you go out squeeze in your BD-5
with your god Jim Bede.

Oh, now I get it. You're a moron. That explains _everything_.

plonk!

Spend a couple
days in Winter Haven at http://www.gate.net/~seaplane/ and get your
seaplane
rating from a living legend. By the time you're a PPA ASEL/ASES and sick
of
Mickey and Donald, your prop will be done and ready to go!

Crikey, Jim, my prop overhaul just became a LOT more expensive!

:-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

But MEMORABLE!! )

"Jay Honeck" wrote in message
news:CBx_e.372157$x96.34581@attbi_s72...
Spend a couple
days in Winter Haven at http://www.gate.net/~seaplane/ and get your
seaplane
rating from a living legend. By the time you're a PPA ASEL/ASES and
sick
of
Mickey and Donald, your prop will be done and ready to go!

Crikey, Jim, my prop overhaul just became a LOT more expensive!

:-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"