Singing propeller, I’m confused, but not .com

[Praxinoscope]

Since replacing a deteriorating 3 blade propeller on my Sadler 25 I have been plagued with what I understand is described as a ‘singing propeller’ at certain revs’.
Have spoken to the supplier who identified the problem instantly and told me to take some coarse emery cloth/wet & dry and slightly round off the leading edges of the prop’. If this doesn’t cure it take it back to them and they will sort it out.
But looking at various advice on the forum about curing a singing prop, some posts suggest to attack the trailing edge .
I’m inclined to follow the advice of our supplier, especially as they are a well regarded marine engineers specialising in propellers, but I’m confuse
as to why there are two opposing suggestions for a cure.

 

[Boater Sam]

Because the cavitation causing the noise can be either edge but most often the trailing edge. Use a file, you will be at it a long time with emery paper.

 

[vyv_cox]

Trailing edge in my experience. Same thing happens with Hobie 16 rudders. I filed a flat on the back edge of both prop and rudders, silences them totally.

 

[Praxinoscope]

Because the cavitation causing the noise can be either edge but most often the trailing edge. Use a file, you will be at it a long time with emery paper.

Inwas going to use Emery cloth as I wanted to work very gradually, rounding off a little then doing a sea trial rather than taking too much off at the start, it also seems to me that with my inconsistent skills with a file, I am more likely to be able to keep the balance of the prop by doing it very gradually.

 

[Boater Sam]

Inwas going to use Emery cloth as I wanted to work very gradually, rounding off a little then doing a sea trial rather than taking too much off at the start, it also seems to me that with my inconsistent skills with a file, I am more likely to be able to keep the balance of the prop by doing it very gradually.

Do as you want but you need to put a 2mm to 3mm flat on the edge, its a fair bit of metal to rub off.

 

[Praxinoscope]

Do as you want but you need to put a 2mm to 3mm flat on the edge, its a fair bit of metal to rub off.

Not sure if I need to take that much off, comparing with the old prop, the really sharp edges represent only about 1mm, still I’ll try it and if no joy livewith ‘BurleyChassis‘ for thé rest of the season ( the engine only really gets used for leaving and returning to the mooring) and take it up to our supplier and let them attack it,.