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Due to several events we ended up not using the boat for 5 consecutive weeks. Highly unusual, maybe the longest period ever. We generally go sailing every weekend.

Noticed immediately that the boat was sluggish as we were pulling out of the slip and confirmed by only managing 2500 RPMs at WOT. Changed all fuel filters and still not getting to full RPM.

Decided to pull the boat and clean the bottom. The hull looked great given that the bottom paint (Petit Horizons) is on its second season. However we had tons of barnacles on the shaft and prop. I don't paint them. Removed them and all is back to normal.

I told my wife the only long term solution is to make sure we use the boat more... :)

In all seriousness, are there any good tips for keeping growth off the shaft and prop? We are in the upper Chesapeake.

Josh
 

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I know of nothing that will stay on for a year, assuming some regular motoring.

I have tried all sorts some so expensive I felt like I was applying liquid gold and nothing has lasted more than three months.

I am in a very high fouling area.
 

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+1 for the Petit Barnacle Barrier. I also use Prop Glop (Moby-Cool.com,barnacle antifouling,paint,a/c hood/hatch). Works great in our harbor in Long Island Sound. It can also be re-applied in the water which is pretty unique. I re-apply several times each season. Any barnacles - which are very few - pop right off with thumb pressure (wear work gloves). I just re-applied today -- prop had very, very light soft growth and maybe two barnacles, but this is the time of year when the warm water accelerates growth.
 

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Corsair 24
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with all honesty the best method is useage...if that cant happen these other things will help at least prolong the heavy fouling

there was a thread a while ago offering numerous methods for props here

everything from beeswax, to grease to antifouling to pepper spray etc

nothing will beat useage...and thats a fact.

when cruising it just becomes a weekly or monthly maintenance things, basically anytime you have a swim take your gear down and do a little cleaning

having said that I would always mitigate the first growths anytime I hauled out by applying a small brush to the prop of antifouling

I like the idea of the petite spray...
 

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Petit Prop Coat Barnacle Barrier 1792 - Spray Cans .... does wonders in keeping barnacles off the running gear
Prop Coat Barnacle Barrier
I wonder(given the zinc content) wether cold galvaniszing spray in a can for trailers and stuff, would offer some of the same benefiits for those of us that dont have access to these kinds of products?

i used the galvanising paint for my iron keel as a primer to spot paint, and later primed and antifouled

which is better than simply painting over bare iron...however I didnt put anything on the prop this time:)
 

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I wonder(given the zinc content) wether cold galvaniszing spray in a can for trailers and stuff, would offer some of the same benefiits for those of us that dont have access to these kinds of products?

i used the galvanising paint for my iron keel as a primer to spot paint, and later primed and antifouled

which is better than simply painting over bare iron...however I didnt put anything on the prop this time:)
I had a unique opportunity to test the zinc theory, in a way. My hot dip galvanised mooring chain was in the water for around 6 months whilst our boat was elsewhere. It had two nylon strops attached that were also submerged. When hauled out of the water, the only difference in growth between the chain and the strops was that the strops had a soft coral growing on them. The barnacle coverage was pretty much the same.
 

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Usually I'm recommending prop speed here, but this year it's been less effective and I don't know why. I've been in the dive gear once already with a paint scraper. Not as bad as no prop-speed as there were only a few barnacles, but in the past it's been 100 percent effective against barnacles here.

This could have been application, change of formulation or changes in my bay, I don't really know.
 

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Well, we have been here before.

Zinc doesn't repel barnacles, on the contrary one could say. The best metal for repelling is copper (Cu), which usually is found in marine propellors.

Propellors with Cu are made in either bronze or brass. It is often very difficult to distinguish bronze and brass by just looking at it, but they are quite different: Brass contain a considerable amount of zinc whereas bronze does not have any zinc (this about the definition of bronze).

In water, brass releases zinc ions, ie some of the metal disappears. This is a rather fast process, as Cu is higher up on the ladder (also compared to water). Consequently, brass metal in water needs an zinc anode.
- the zinc andode is usually consumed rather fast, which gives some indication of how much zinc may be released from the propellor.

Bronze however, is another matter, at least another alloy! Not at all the same process, there is no real need for a zinc anode. Without such, a small amount of Cu ions will be released and ... barnacles will not attach!

Thus, it is easy to get rid of barnacles if one has a propellor made of bronze.

Problem is, of course, to know that it actually is bronze. Very few, if any, propellor manufacturer state that they are using bronze - and some clearly use brass.

If one is using a zinc anode, the only way to prevent - to some extent- barnacles is to paint with some anti-fouling made especially for props. In that way one can enjoy a much higher price as well.

/J
 

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Swim with brush and a greenie tied to your hands, sometimes a scrapper in your pocket, prop coatings last for a while but if you want multiseason and no haul outs you either get a diver to scrub you down or you do it yourself.
 

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yup...no way around it if you dont use it regularly

I just scraped my bottom after only 4 months or so since new paint, places already had barnacles and weeds and stuff...

warm murky estuary water grows like crazy!

peace
 

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Last year this was a major issue. So scraped then hand sanded down to automotive paper. Then two coats petits spray and two coats very thin layers of petits water soluable bottom paint. Works so far. Boat is run near daily for a week or two. Then sits for about a week ten days. In marina on slip with out much current.
Big disadvantage to prop speed is need to get back to bare metal before each reapplication and expense. See variation in effectiveness if done by yard or owner. Petits spray seems idiot proof- just right for me trying to DIY as much as possible.
 

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Amazing to me that anybody would haul a boat to clean it, especially in an area where hull cleaning is an actual industry, like the Chesapeak Bay.
The marinas are catching on it seems and offering fairly cheap quick hauls around here, especially if you pay cash ;)

I had always kept our boat in a working marina so a quick haul was easy and gave ME the chance to inspect the boat. When I moved to a club with no haul out facilities I started using a diver. Granted, I have only used one diver so far...

So before our trip I had the diver come inspect and clean the haul. Then after he came about 10 days later I decided to have the boat hauled so I could adjust the pitch on my prop (Autostream feathering prop), the marina owner almost insisted I do this instead of diving myself, so I followed his advice (he offered me a fair price to do a quick haul)

Sure glad I did because what I found is the diver didn't do as he said he would. Barnacles on the shaft and prop. Fine hair like growth all over the hull except near the waterline, and areas that needed some paint...point being I was very disappointed in the services provided by the diver. Which made me rethink the entire diver thing to be honest. On the Chesapeake bay the reason I would hire a diver is because I don't like to dive on a boat when I can only see a foot if that, creeps me out:rolleyes:.

I am certainly not implying all divers suck as much as this one, but if you don't check for all we know they're having a beer in the cockpit and charging me $100 for it. Not saying of course this is typical, but certainly makes me skeptical and if I hire a diver again, I will certainly check their work.
 
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