Underwater grease

Joker

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I am going to replace the blades on my folding prop whilst the boat is out of the water, and I want to make sure the folding mechanism is well greased. Is there any particular type of grease which is better than others, or should I just use a generic grease?
 
I'm not convinced greasing a folding prop is a good idea. It's not as though the blades of the prop are in constant motion with respect to the pivot. They swing once when you start and once when you stop. Add grease and you add a sticky substrate to carry a load of sand and grit around with you. Without grease any grit is as likely to be washed out as in.
I've never greased my folder and it's as good as the day it was fitted.
 
Different manufacturers of apparently similar props give different instructions - the Volvo propellers are supposed to be greased, whereas the Flexofold are not. It's difficult to see that they are much different in design and operation of the folding system, though I guess different materials might make a difference?
 
Different manufacturers of apparently similar props give different instructions - the Volvo propellers are supposed to be greased, whereas the Flexofold are not. It's difficult to see that they are much different in design and operation of the folding system, though I guess different materials might make a difference?

And the seas you are sailing in I guess? In Croatia the sea is crystal clear without any suspended sand or grit and no-one dries out on mud or sand, of course, so greasing the prop is probably a good idea. Possibly not on the UK East Coast though!

Richard
 
I think it was Vyv who first told me that Calcium grease was the stuff to look for.

Mind you, when I did O-level Chemistry we used to chuck pieces of Calcium metal into a beaker of water and I'm sure it fizzed and gave off hydrogen. Let's hope the grease is a little less exciting! :)

Richard

Wimps! We used to throw sodium off the bridge into the canal on our way to lunch. Best was to put it into a tin with a couple of holes banged into it, made a satisfying bang.
 
Any views on using Tectane white grease aerosol (not for chucking in canals) for greasing seacocks? Salt water resistant and easy to apply when ashore?
 
I am going to replace the blades on my folding prop whilst the boat is out of the water, and I want to make sure the folding mechanism is well greased. Is there any particular type of grease which is better than others, or should I just use a generic grease?

I suggest you consult the instructions for your prop. Hopefully they will be on line.
You do not say what propeller you have yet you ask for advice on the type of grease to use. Some should be greased, some should not!


The instructions should tell you what type of grease if any to use. Almost certainly a water resistant calcium based grease will be required but you also need to consider the consistency grade. Commonly available greases fall into the 1 to 3 range .

A grade 3 grease is what we would normally consider to be a heavy or firm grease and may well be to thick

A grade 1 grease is a soft grease.

A grade 2 grease is intermediate ( A "normal" grade

Of the greases mentioned

Millers water pump grease is a grade 4 calcium based grease. It would only be suitable if a very firm grease is required.

Morris Oils Water resistant grease is a grade 2/3 calcium based grease. It would be suitable if a medium to firm grade is required

Ramonol White grease is a lithium based grease but is described as water resistant. It is a grade 2 grease

Ramonol Advanced grease is a calcium sulfonate based grease and is described as highly water resistant. It is a medium/soft grease grade 1/2

Clare Dr Barnacle grease is intended for coating propeller blades to prevent fouling

Tectane white grease aerosol spray is said to be very salt water resistant but I have found no technical info. I have a can . Not impressed. Not suitable IMO


Of the above my choice would be Ramonol Advanced unless a heavier grease is called for. It's readily available from chandleries.
 
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So, 12 months in the drink, not one barnacle on the prop using this jollop (discovered on this very forum):

http://www.rsclare.com/dr-barnacle/139.html

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