Rotten prop

[roger]

I've had a nasty shock. My two year old prop developed measles - copper spots - and lost its healthy ring when hit.
When I removed it I found the shaft anode had a layer of corrosion between it and the shaft. That was something I hadnt checked the previous winter. - silly and expensive.
Now of course I've upped the bonding all over the place.
However the guys who sorted me out with a new prop said that the prop was Italian and of a make that he no longer supplied because they seemed to rot very quickly. He said this idea was supported by the observation that neither the shaft nut nor the key were affected.
Incidentally he also measured the old prop and read off the individual pitches of the three blades. In my naive way I was impressed. He also did the job quickly.

<hr width=100% size=1>Roger

 

[byron]

<font color=blue>Maybe you haven't suffered the ravages of electrolosys at all, maybe the prop was made of hardened spaghetti then covered with a metallic paint.

<hr width=100% size=1>http://www.alexander-advertising.co.uk

 

[AndrewB]

I've reported before on problems with Italian brass imports. Replace it with Phosphor-bronze or Alu-bronze (AB2), not manganese-bronze.

Even so, the old one should have lasted more than two years. While you are right to up the protection, you might question why the electrolysis is that high.

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