Propeller - to polish or paint? That is the question.

Poignard

Poignard

Well-Known Member
Joined
23 Jul 2005
Messages
55,658
Location
South London
Visit site
During the 9 years I have owned her and for an unknown period before that, my boat's propeller has been antifouled. This winter I have scraped all the anti-foul off to see if the prop has any corrosion or cracks. It looks ok and is now nice and shiny.

But. does the team think it best to leave it bare metal or is it best to antifoul it? Pro's and con's, please.
 
Telepathy?

I've just logged on to the forum to post a similar question about treating props. Ours is covered in the remnants of some marine growth, so I was going to ask about removal/coating.

I'll be interested in responses to your question...
 
Two years ago my prop was fouled so badly that the engine became overloaded at high revs.Lots of unburnt fuel pumped out of exhaust at higher revs.So I had her lifted and cleaned off prop.At LIBS 2005 spoke to various stands and could get no definite answer.Antifoul makers say antifoul.Prop makers say clean and polish and send back every few years for re-grinding.Boat manufacturer said don't antifoul as you can't see whats happening to prop under antifoul.Last season I applied a very thick layer of lanolin (available in 500Gm pots from most pharmacies) and when I lifted mid season there was very little fouling.So going to stay with lanolin for another season.
 
I used to antifoul, and got the same sort of light coating of barnacles as the rest of the hull. Now I polish, and get exactly the same results. One year I forgot to apply any polish, which was a big mistake. By that October, any tidal stream over two knots would stop her dead under power.
Never tried anhydrous lanolin, some swear by it others say it's a waste of time.
 
My boat's prop is now 38 years old. It shows very slight electroyltic degradation - nothing that I am going to worry about. I don't know what the previous owner did with it, but for the last 22 years I've antifouled it.

It seems to me that a sailing yacht's prop is in use for such a tiny proportion of the time that antifouling is the logical thing to do. I certainly would not antifoul the propeller of a working boat, still less a ship.
 
I use "Zeebrite" on mine, its the stuff used for blackening fire grates etc.....I have used it for the last 4 years and works a treat. Clean up the prop first so its shinny clean then apply Zeebrite paste and polish, when dry add a few more coats and buff off.

Paul.
 
I have polished my Bronze Prop to a hi shine and thinking what to do now.
On my first boat with an Alloy Prop I painted it (the Prop) with twopack epoxy including primer did a good job. I also tried Lanolin IMHO waste of time I had to beach her (The Boat) to remove all the crud half way through the season. I have also tried Prop / Saildrive aerosel antifoul (forgotten name) and primer 'OK' only result. But now have Bronze prop I am tempted to leave Highly Polished.
 
I used Zebo grate blacking last April - I presume it's the same stuff as Zeebrite. Where I'd put it on thickly, I had no barnacles in October. Where it was too thin, I had a few, but less than on the antifouled skeg nearby. I intend to try again this year, but put several coats on.
 
Last winter I gave my son 2/6 after he spent 2 hours cleaning the prop and shaft to a brilliant shine, it looked so good I did not antifoul it. when she came out this winter I realise it was a big mistake, it was caked in barnacles
 
have you ever seen a commercial ship with an antifould or polished propeller ?

The new propeller I just received from Radice in Milano was not polished, actually it was rather looking unfinished. When it was given to me, they explained that this is the new way how propellers are made. My italian friends picked it up at the factory for me, so I was unable to ask the italian engineer specific questions. My old propeller was smooth and polished.

I have read somewhere, unpolished propellers create less cavitation due to the disturbed waterflow across the "unfinished" surface

It workes for me, I'm doing 0.5 knots more with the new propeller, same size and same rpms. No cavitation noise like the old one had. I had to change due to new engine turning the other way.

Peter
 
I have started using Trilux on my propellor because I had some boot-topping paint left over and noticed it mentions propellors on the tin. It stops the fouling increasing as rapidly as having nothing at all and seems to stay on the prop for about 6 months.
 
I painted my bronze propeller with Seajet Peller Clean last year and was quite pleased with the results - just a few tiny barnacles at the end of the season. The previous year the prop was so badly fouled half way through the season I had to dry out to clean it off. The snag is the cost, which was about 30 pounds. I will be using it again this year though.
 
My vote is with the polish it faction but it has to be polished really bright to a mirror finish and this is where I think many poor results come from. Initially it takes a lot of effort with wet & dry paper starting with say 360 to clean it, then 1000/1200 to polish out the scratches from the 360, followed by several goes with Brasso. It will tarnish slightly a day or so after the last Brasso polish so if possible give it another quick polish just before launching, we do ours the night before.

We lifted out yesterday having launched last February so nearly 12 months afloat, our Brunton prop had a few barnacles in the root of the blades by the hub and a coating of slime and scale. The pressure wash took off the barnacles and I used an old sail batten to scrape the scale/slime off under which there was still the mirror finish, however I did do this within a couple of hours of liftout before the stuff hardened off.

Over the years I unsuccessfully tried antifoul and lanolin (the sheep are still laughing but I don't have a chapped ar$e anymore) and the guy at our club who SELLS Pellor Clean or whatever was heard saying it was a total failure on his own prop but at least he wasn't stupid enough to pay for it!

Where I have no solution though is for the exposed S/S propshaft and our current boat has this arrangement whereas previous ones had the shaft enclosed. I have tried Trilux because I had some in stock and it was as useless on the shaft as it was as a bootop. I tried polishing it but it isn't bronze so has no copper content and it was as bad as before, so maybe this time I should try the rest of the lanolin whilst the sheep isn't looking.
 
When I first bought my boat a helpful soul at the club told me that a nice bright prop was sufficiently poisonous in itself to keep off marine growth. I believed him. A month or so into the season I dried out to see how it was doing and was amazed that the ball of barnacles on the end of the prop shaft could drive the boat at all. Ever since then I have antifouled prop and shaft (except of course for the bit where the anode goes) and have had no problems.
 
For the last 20 years I have polished the prop and then coated it thickly with Castrol Heavy grease! - Works very well for me. Not sure what difference the grease makes - - probably gives the barnacles indegestion.
 
You must log in or register to reply here.

Share this page

Top