It's not a sin to disagree Graham, I forgive pretty easy, and thanx for sharing your experience with Micron on your Kiwi prop in the Northwest Arm, Bob can have hope for protecting his 2 blade bronze prop with Micron 66.
OK, some paints, like baked on epoxies and hard paints that etch the metal to achieve stronger bonds may stand up to prop cavitation better than others and of course some props because of design will develop less cavitation. I see that as the case on the little 3 blade prop on my 9.8 Tohatsu outboard that drives my inflatable, and I run that engine full out quite often and the coating seems to stay on the prop blades OK Dwight Veinot C&C 35 MKII, Alianna Head of St. Margaret's Bay, NS -----Original Message----- From: CnC-List [mailto:[email protected]] On Behalf Of Graham Collins Sent: January 8, 2013 10:41 PM To: [email protected] Subject: Re: Stus-List Prop Mussel Farm I have to disagree with that Dwight. My previous boat had a Volvo saildrive with an aluminum prop. It was original (20 year old) factory paint on it when we got it, but the change in mooring location was enough to prompt a few pounds of barnacles to live on it, which destroyed the paint Volvo had applied. After a couple of trials, what worked was applying Interlux Primocon and a couple of coats of bottom paint, with the aluminum I had to use Tri-Lux II. No issues with the paint coming off, I would just apply a new coat of antifouling in the spring and never had to put on more primer. I did not see exposed metal anywhere, including the tips. Side note, I now have a kiwi prop, and the plastic blades require antifouling paint. A coat of Micron does the trick, I may have two or three barnacles on it at the end of the season. Given my proximity to Bob's mussel farm it means either the Micron is working, or I'm getting some sort of halo effect from Rich's prayer sessions... Graham Collins Secret Plans C&C 35-III #11 On 2013-01-08 8:05 PM, dwight veinot wrote: > Sorry Rick > > But I don't think the primer will add much unless it too is an antifouling > paint. > > Under the influence of tip vortex and face sheet cavitations on the prop > blades, especially at high rpm, most paints will be removed, regardless of > and including most primers...IMHO best you can hope for with antifouling > paint is to give better fouling protection to the shaft and hub of the prop > where I believe the effects of cavitation are less severe, and some shorter > term protection to the blades which I would suggest might last longer if the > boat were driven at lower rpm rather than full out > > Dwight Veinot > C&C 35 MKII, Alianna > Head of St. Margaret's Bay, NS > > -----Original Message----- > From: CnC-List [mailto:[email protected]] On Behalf Of Rick > Brass > Sent: January 8, 2013 7:52 PM > To: [email protected] > Subject: Re: Stus-List Prop Mussel Farm > > In North Carolina we don't have much problem with mussels, but the > relatively warm water, moderate currents and abundance of nutrition in our > rivers and sounds lead to constant struggle against a lot of barnacles. > Being a multiple boat owner, I've had a lot of experience over the years and > paid a lot for divers to clean my props. > > The last straw for me was when I took the 38 to Beaufort for some work in > the summer of 201. Hull speed is about 7.3 kts, and I motored down there at > 6.5+. Why not? The boat had been splashed just 3 months prior and the bottom > job was brand new. On the way home, about 3 weeks later, I could make only > about 4 knots. Man, were there a lot of barnacles on the (unpainted) prop > and shaft. And since I planned to take the boat south it seemed like I > better do something to avoid future growth. > > Once I got the prop cleaned, and since I've already tried bottom paint on > the prop and shaft (it does not stick very long if you use the motor very > much - call it 100-150 NM of motoring in my case), I started asking to see > what others in the area do. > > The information that I got is that the commercial fishermen in the area > usually paint the prop and shaft after using a two-part primer that will let > the paint stick. The primer is a two-part product called Pettit Metal Primer > #6455. You clean all the old organic material off the prop and areas of the > shaft that will not be covered by the zincs (I actually sanded with 80 grit > until it was shiny and well scratched up, but was told this was not > necessary), mix the primer, and paint it on. After 24 hours of cure time you > put on bottom paint. The preferred paint in these woods seems to be Pettit > Trinidad Pro. I was told that ablative paint like Micron 66 and Pettit Ultra > will stick, but slough off fairly quickly as the boat is used. > > The Pettit primer wasn't particularly cheap - about $65 IIRC for about a > pint of primer after mixing. But if it will make the bottom paint stick it > is probably a good value. And the local fishermen, who use their boats 5 or > 6 days a week pretty much year round, seem to swear by it. > > It's only been on my prop for 6 months or so, but so far I'm very happy with > the results. > > Of course, your results may vary. > > > Rick Brass > Washington, NC > > > > -----Original Message----- > From: CnC-List [mailto:[email protected]] On Behalf Of Robert > Abbott > Sent: Monday, January 07, 2013 1:55 PM > To: [email protected] > Subject: Stus-List Prop Mussel Farm > > there is one more 'remedy' I have heard/read about......it involves coating > the prop/shaft with "galvanized zinc spray paint". I have never seen this > done and do not know what effect it might have on the bronze prop (shouldn't > be negative but I'm not sure). There is never any marine growth on my > sacrificial zinc(s). > > Has anyone heard of this? Anyone with any experience with this paint on > props? > > Bob Abbott > AZURA > C&C 32 - 84 > Halifax, N.S. > > > > > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > [email protected] > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.2221 / Virus Database: 2637/5518 - Release Date: 01/08/13 > > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > [email protected] > > _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com [email protected] ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2221 / Virus Database: 2637/5518 - Release Date: 01/08/13 _______________________________________________ This List is provided by the C&C Photo Album http://www.cncphotoalbum.com [email protected]
