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View Full Version : Chipped props -when to fix


foghorn
30th May 2002, 17:49
At what point would you say a propeller needs a urgently filing (as opposed to getting it done at next convenience?)

Chip in the outer third?
Chip wider than a couple of millimetres?
Chip deeper than 1mm?
More than 1mm metal standing proud of propeller surface?

I'd be interested in your thoughts.

cheers!
foggy.

Steamhead
30th May 2002, 20:32
The highest stress area is 6 to 9 inches from the tip and anything significant in this area is very important.
Outside of this area then it has to be a substantial ding to require maintenance attention.
regards

Splat
31st May 2002, 10:48
Foggy,

I was told even minor dents should be dressed out(I believe that's the term). It was explained to me that the uneven surface put stress on the surrounding area.

I've always made sure that the engineers look over it.

S

PS, be a shame on that Tiger of yours.....

foghorn
31st May 2002, 11:35
Splat,

Luckily, I managed to find an engineer who would dress it today ;)

RatherBeFlying
31st May 2002, 12:37
The one time I found a nick, the time finding an engineer exceeded the time he spent redressing it -- much better to fix a small nick quickly than have to deal with a big one:eek:

UAM
3rd Jun 2002, 20:00
The comment regarding highest stresses, I take it that would be bending rather than axial stress? Reason I mention this is because the axial stress is highest at the root as would be bending stress to think about it ( depending on varition of CSA) so not sure where you get this heuristic 3-4 inches!
Dont know anything about the practical side of prop repair, but coming form a stress analyst background on turbine blading, thought it would be an important addition.

Checkboard
4th Jun 2002, 04:53
Ahhh, but the blade root is a big thick round thing - chips don't become critical until the blade thins out.