Prop nuts

[macd]

The only example I can think of which equates to "negative torque" is tapered bearings in some car wheels .... but these are a moving part.

And motorcycle steering head races. You can probably imagine how easy it is to feel when there's too much 'negative torque'. Or too little.

 

[RichardS]

And motorcycle steering head races. You can probably imagine how easy it is to feel when there's too much 'negative torque'. Or too little.

Yes .... another good example Mac.

Richard

 

[savageseadog]

Best way of locking a prop nut would be a left hand thread axial locking bolt or nut on the end of the shaft. Even Yanmar have got this wrong on their saildrives, the nut and the locking nut are both RH thread. They used to have castellated nuts and pin but the hole through the shaft weakened it and the end of the shaft used to break off.

 

[Neeves]

Tab washer, new one each time, and Loctite.

Jonathan

 

[zoidberg]

We watched with a mix of sympathy and hilarity, some years ago, at a 'needle match' rival who lost his £800+ prop maneuvering before the start of a Fastnet Race. He owned a 40' lightweight Dazcat with a bigger rig and new sails. We had a 33' homebuilt tri, but still beat them both on the water AND - despite their having the class handicapper aboard and we 'having to give them time' - on Corrected Time.

He didn't Declare that he'd sailed the race with no prop, contrary to the Rools.

I've taken an interest in prop nuts ever since.....

 

[LadyInBed]

Tab washer, new one each time, and Loctite.

Jonathan

Mine got reused!

 

[Robert Wilson]

New brass 3-blade prop with brass washer and brass nuts (on s/s shaft).
Prop bought from FAL at Buckie where they said fix with Loctite. No split pin as previously.

I shall do as I'm told, but I'm inexperienced with Loctite for such a vital "hold".

Fingers crossed.

 

[Neeves]

Mine got reused!

There is an attraction

- but they might fail, they are as cheap as chips, certainly cheaper than a new prop (though inordinately expensive for what they are) and with a bit of foresight - they will be ready when you need to take the prop off.

In my book - Its simply not worth it

Jonathan

 

[Topcat47]

I changed a mild steel castellated nut for a bronze plain nut and tab washer because the split pin never quite lined up with the castellations when refitted. The washer is "soft iron" rather than steel and certainly NOT SS.