View Full Version : Propellor fouling

11-08-2002, 05:15 AM
I do not put any anti fouling on the propellor and am thinking of ways - quite apart from diving on the propellor weekly which is sometimes left undone as a result of a hcetic travel schedule - of preventing marine growth. It is very rapid here in Singapore - one month can see extensive growth which is a catalyst for further growth. I just hauled Maybritt and the propellor was beginning to resemble a coral Reef.....

I have been thinking of using neoprene socks similar to those used on power boats and as sold by West Marine but I may not now get round to that for some months as it is probably best measured/fitted when Maybritt is next out of the water.

A mate of mine suggested using a black bin liner over the propellor but I do not know of anyone who has used that system and I am far from convinced that it would work - does not marine growth occur even in virtually no light ?

I wondered whether a coating of waterproof grease might help renewed everytime after the boat is used but perhaps marine growth would then be even more vigorous or perhaps it simply would not be very effective.

Does anyone have any (useful) comments to make or helpful suggestions apart from Dive Dive Dive that is !?

11-08-2002, 05:29 AM
Provided you use the boat regularly, I'm told that a coating of lanoline (the grease from wool) works wonders. By reguolarly, I believe that once a week is the go.


11-08-2002, 10:31 AM
Ian, at risk of being curmudgeonly, isn't diving once a week to smear on lanoline very similar to diving weekly to wipe off any marine growth? ;)

Sorry that I don't have anything constructive to add - in my neck of the oceans the water is too freakin' cold to get much rapid marine growth, which is a good thing 'cause it would take an hour to suit up for the five minute dive. :D

Ian McColgin
11-08-2002, 10:44 AM
What kind of boat and why not antifouling on the prop. There's some great hard paints that go on without affecting balance or hydrodynamics on all but wierd high speed props like surface piercers.

11-08-2002, 10:56 AM
Ian, "Maybritt" is a substantial young cutter, built properly, of teak, and kept in Singapore and/or Thailand. Her owner, Andrew Wilding, is one of the few contributors here whom I have met.

Having said which, Andrew - why not antifoul the prop? I do. The a/f does wear off, but it certainly helps - I get weeks at a time, not days, with a clean (ish) propeller. Working craft don't antifoul their propellers because these are in almost constant use - but such is not the case with a sailing yacht.

11-08-2002, 12:54 PM
same problem with fathometer transducers -- y'arnt sposed to paint 'em. Last March I tried the anhydrous lanolin treatment . . . this coming March I'll let you know how it worked. So far not a big blob of barnacles such as I usually have by this time. I put it on when the boat was dry -- probably stays better.

martin schulz
11-08-2002, 12:55 PM
Great thread - no really.

I have the same problems. I use my engine very seldom, since it is custom to do every maneuver under sail in the "Museumharbor-scene". It was hard to get used to, but on the other hand we still have a lot of ex-working boats without engines. And those are sometimes big and heavy 2 mast boats. And then it is good to know how to handle your boat without engine, like using the anchor not only for anchoring.

But, I do have a small diesel (8HP for my 4,5tn -by the way, those are Themse tons, how much "normal" tons are they). And once in a while I have to use the engine and then it is the same thing - the prop looks like a reef. Last week I couldn't even gather way. I had to get in the f****** cold water to scrape the *%&-shells off.

John B
11-08-2002, 05:00 PM
The proper first application of lanoline is supposed to be done hot.Prop off... stuck in the oven etc. Sounds like a lot of fuss to me but.....
There's a teflon treatment done that way too.I met a man doing it but haven't caught up with him again to ask how it went.
I understand the best way to antifoul a prop is to ensure it's primer coated first.

The last couple of years I've been polishing my prop on the buff at work first off and then doing the lanocote thing just to get a start into the season. Polishing it seems to get a good waxy feel to it and the lanoline grease backs it up. How good is it? subjective ,but definitely better than doing nothing.

11-09-2002, 03:29 AM
orig. posted by mmd

isn't diving once a week to smear on lanoline very similar to diving weekly to wipe off any marine growth?Further explanation needed here. The lanolin, as mentioned by others is meant to be applied hot, ie at 70 degree Celcius (It was 41.5 degrees C here today - and that is BLOODY hot! - especially when you split over 5 tons of firewood)

I've seen it done with guys using a propane torch to heat the prop.

You don't need to apply it once a week - you need to use the boat at least once a week once its on, otherwise the prop fouls again.


11-11-2002, 03:25 AM
Iain ! Maybritt is a 18 ton/47ft Chengal Ketch. ACB ! Yr mind is going - but then again it is a long time since we met and the pints of Ruddles might have dimmed your perceptions some what! I have offered a return drinking match in your neck of the woods but my e mails in that regard have been spurned !

Maybritt has an 84 HP Perkins working a Hunderstadt variable pitch prop - a two bladed monster of a thing. The blades/hub present a huge surface on which to grow

Iain/ACB I do not use antifouling for reasons of practicality more than anything else. If I could make it stick fine but it always seems to wash off - the engine is usually run most of the way to (for eg Thailand) or at least as far as Langkawi and until the Trades are reached.

Further with a highly polished prop/Hub it is arguably better than antifouling which creates a rougher surface on which the nasties can grow ?

I am anticipating leaving Maybritt for good few months in Thailand when she finally makes the next trip up so I am very keen to try and avoid growth whilst she sits in the Boat Lagoon Marina in Phuket....

Anyone try a black bag o which I heard a variant over the weekend of injecting tile grouting cleaner (TBT) into the bag once fitted with a syringe...now I have heard it all.

I'll have a look for Lanolin ( no sheep that I know of in Singapore) in any event I doubt that the prop/hub would fit in the oven.....Baaa Baaa

John B
11-11-2002, 02:00 PM
The brand name in NZ is Lanocote if that's of any interest.

11-12-2002, 12:16 PM
Well ... outrageous idea: build an air-tight box that will fit over and cover the top, ends, and sides of the prop (which has to be turned to horizontal, perhaps) and a bit more. Needs a little door so the shaft can reach into the box. Put the box over the prop, close the door, fasten in place, and then fill the box with air. No water, no marine growth. Remember to remove the box before moving the boat.

How about bubbling air over the prop from aquarium bubblers mounted below it? Little air pump mounted on deck, perhaps solar powered?

Bill Dodson
11-12-2002, 03:49 PM
I think the idea with the black plastic bag is no light, no growth... a little easier than removing the water from the prop?