Antifoul - options

[Dave 6]

Thanks for the reminder CD, I'd intended to post an update on the MacGlide post sailing and hopefully have some photos/video to share but I haven't actually managed to use the system as intended yet so was holding off until I had done so.  In any case here's some impressions that I have so far.

The boat had a fairly thick layer of slime on it with some obvious small barnacle action and hard wormy type things on it after about 8 months up the river.  On the initial sail I managed to get the speed up to 10kts for reasonable periods but there was no perceptible self cleaning evident after the sail.  I subsequently dove on the boat and cleaned the hull; I used a really soft sponge and the majority of the fouling came off very easily, one gentle wipe was enough to get rid of it.  However, there were patches of some sort of plaque-like growth, some quite large (dinner plate size) that required dislodging with my fingers.  It did come off easily enough I suppose, although I was concerned that it might have damaged the film but I'm yet to confirm this.  Overall really easy to clean.

The next sails were excellent, huge performance increase as you'd expect, and the hulls (trimaran) remained clean.  As it was only a few days between outings though there wasn't time for the hulls to foul much.  I haven't managed to get out to the boat for three weeks now so when I do I'm expecting to see a slimy bum without much crustacean growth...hopefully.  I'll decide then whether to sail and see if it cleans, or clean it and go for a sail.  The driver for that will be the amount of hard fouling I find.

Sorry this has been long winded, I mentioned at the start that I hadn't used the system as it was designed.  I'm not disappointed at the amount of growth it had, nor it's persistence, as I admit I didn't give it a fair go.  It appears likely that if sitting on a mooring without use it will need cleaning periodically (3-4 weeks?) but if the boat is used regularly it will do what it says on the tin.  

One last comment - once the hard fouling (barnacles, worms etc.) had gained a foothold I noticed that fish were feeding off the hull.  As a result there are areas around the waterline where the fish have nibbled the wrap and left a fingernail shaped and sized divot in the silicon.

More to come...

 

 

[Dave 6]

I tend to agree Tamure, I had hoped that it would have been a bit of a "silver bullet" in the war on fouling, but realise now that its probably not quite there for the majority of prospective users.  By that I mean that to get the benefit out of the wrap I think you'll have to be pretty stringent on maintenance if you're not using the boat regularly.  Leaving it as I did for so long was asking for trouble so have only myself to blame. 

From a cost perspective the wrap was around $4.5k, as well as probably $2k for the hull prep and paint.  The product is warrantied for 5 years so for me it will ideally cost $1300 per year over it's life, still dearer than hauling and antifouling but it 'should' be a bit less hassle, we'll see about that.

I reckon it will be a good solution for launches that are used reasonably regularly, with the added bonus of fuel savings for them due to the claimed drag reduction of the silicon.  I'm interested in how your mate gets on, there's also a couple of power boats that have been done at Stillwater so when I run into them (not literally!) I'll see how they're getting on. 

 

 

[Fish 803]

I've ordered some of this silicon wrap to go on my prop shaft (yacht). We don't haul out, as we have copper coat. The prop speed has warn off, and I'm wanting something I can apply between tides. Should be an easy option to try, and not much to loose if it doesn't work.

Even if we don't go out often enough, I do tend to give the engine a run and spin the prop every two weeks or so on the mooring, so hoping it will stay clean. Randomly, I think the fouling on the shaft is damaging my cutless bearing - the growth on the shaft is blocking the water flow through the bearing. Historically I've been getting through cutless bearings faster than I should, which I put down to an alignment and vibration problem. Now we've got a new engine, the only vibration is from the cutless bearing...

[Black Panther 821]

Interesting.  I would try that for prop and shaft. Using lanolin at present. 

[Clipper 208]

How often so you apply lanolin? My propspeed is had it now. You apply it with a rag in the water??

[Black Panther 821]

Rag in water. About every 4 to 6 weeks.  Let it go over winter coz I'm a pussy.  Had to scrape clean and start again.

[Dave 6]

Might work, I seem to recall that there's a top speed for the wrap above which it's not recommended, the guys at MPS will tell you I'm sure.  I don't know what the relative 'boat speed' of a propshaft is at revs but I guess you could work it out algebraically.  I hope it goes well for you.