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CJ
02-15-2010, 09:57 PM
Stainless rudder and NIBRAL prop. Although the boat sees moderate use, I still get a lot of growth on the prop & rudder in Connecticut waters. Looking around the yard, I see some boats have painted running gear and others don't.

Should I paint them? And, if so, just use the same antifouling bottom paint that's on the rest of the boat? It sure works on the bow thruster props, but they're plastic. Any unique preparation work that would need to preceed painting on these materials? Any drawbacks to painting them?

Thanks,
CJ


http://i255.photobucket.com/albums/hh147/cjg0601/RunningGear.jpg?t=1266288410

boylesboats
02-15-2010, 10:15 PM
I wouldn't paint the prop.. it may change the prop's profile, increases the un-necessary drag that cost fuel..

for rudder? find some good primer for painting onto stainless steel, then paint it with your choice of paint... Other than that just have it powder coated

Bernadette
02-15-2010, 10:21 PM
paint anything that's underwater to prevent marine growth. use a metal primer and then anti-foul both. painting wont change a prop's prifile. paint thickness is only measured in microns not inches and unless you have a ' high performance hull' you wont notice any extra drag.

nedL
02-15-2010, 10:27 PM
Here in CT, with any reasonable use of her I'd paint the rudder & maybe the hub of the prop & not the blades.

So when do we get to see her topsides CJ?

boylesboats
02-15-2010, 10:29 PM
use a metal primer and then anti-foul both. painting wont change a prop's prifile. paint thickness is only measured in microns not inches!

then it doesn't change much on slow speed props.. I couldn't tell if his prop are cupped in the photo..

Most high speed props left in bare metal for precision functions

I could say it is wasted effort paintin' props.. as water will wear the paint off within few hours of operation

PeterSibley
02-15-2010, 10:32 PM
If you can get it there , experiment with Lanocote ,a lonoline grease that sees a good and ultra thin anti marine growth barrier .The prop would be the ideal test bed .

http://www.cruisersforum.com/forums/f114/antifouling-a-prop-12961-5.html
http://shop.sailboatowners.com/detail.htm?group=1147
http://www.woodenboat.com/forum/archive/index.php/t-46426.html

Todd D
02-15-2010, 10:50 PM
I wouldn't paint the prop. Unless you properly prime the stainless rudder and use a hard epoxy type paint, prop wash will scour any paint off in short order.

Breakaway
02-15-2010, 11:20 PM
Agree with Todd on the prop--antifoul wont stay put. I paint the stainless trim tabs on my planing powerboat with spray antifoul intended for outboards and sterndrives. Its cheap and quick:scuff with scotchbrite, three coats of spray-on zinc primer and three coats of antifoul. The paint holds up for a 8-month season in the Northeast and I cruise at 24-knots. It should do at least as well on your rudder. (dont paint the rudder shaft underthe collar zinc, or the zinc itself, you have installed there in the pic!)

boylesboats
02-16-2010, 01:06 AM
Now there we goes.. that make three of us disagree on painting the prop

Why spend $50.00 a pint of paint on the prop, that'll be worn off in short time..

RFNK
02-16-2010, 01:46 AM
Well, it's common practice here on the east coast of Oz as, otherwise, the prop quickly builds up a lot of growth that upsets prop performance. This stuff is quite expensive, I think, but it's specifically made for the purpose, unlike other antifoul. i can't see why this wouldn't be suitable for your rudder as well as the prop IF it is indeed necessary to antifoul the prop where you live. Rick http://www.prop-shield.com/

Larks
02-16-2010, 02:53 AM
I tend to think anitofouling a prop is a wast of time as it comes off pretty quickly and where it does stick it will cause pitting in the prop (if I go hunting I could probably find some photos of this if anone doubts it).

But I 'll second the lanoline based products Rick and Peter, the one in the link is pretty much the same as Lanocote by another name as far as I'm aware. I was given something similar but by yet another name, though still lanoline based and used it when sailing up around Indonesia, Malaysia and Thailand and it was quite effective, stuck well to the prop and caused no risk of pitting.

Candyfloss
02-16-2010, 05:11 AM
Props don't work very well with barnacles on them either. You'd think the little buggers would get giddy after a while & drop off, but they don't. When I canvassed the Yacht Club I got about a 50/50 response, so I antifouled it. The a/f wore off pretty soon. I later found a special prop a/f, made by one of the big outboard manufacturers, which cost a king's ransom but worked much better.

I was told that copper a/f would cause electrolysis on the prop, but I saw no sign of it in mine.

michigangeorge
02-16-2010, 05:54 AM
Back in the days we kept boats in saltwater I seem to remember something about boiling the props in oil. Has anyone heard of this or did I just get up too early this morning?

Dale Genther
02-16-2010, 07:58 AM
For about 10 years I've been painting my props (bronze) with Petit Zinc Coat Barnacle Barrier Petit # 1792). It is the only product I've found that actually works and stays put for a full season. It is mostly zinc. A lot of people here use it and the only report I got of it not working was on one boat that had no zincs. I'm assuming the Zinc Coat acted as a zinc and disappeared quickly.

David Tabor (sailordave)
02-16-2010, 09:03 AM
For about 10 years I've been painting my props (bronze) with Petit Zinc Coat Barnacle Barrier Petit # 1792). It is the only product I've found that actually works and stays put for a full season. It is mostly zinc. A lot of people here use it and the only report I got of it not working was on one boat that had no zincs. I'm assuming the Zinc Coat acted as a zinc and disappeared quickly.


Exactly what I was going to recommend! Sprays on like spray paint, looks like primer. Just do lots of thin coats.

Bob Triggs
02-16-2010, 02:07 PM
For about 10 years I've been painting my props (bronze) with Petit Zinc Coat Barnacle Barrier Petit # 1792). It is the only product I've found that actually works and stays put for a full season. It is mostly zinc. A lot of people here use it and the only report I got of it not working was on one boat that had no zincs. I'm assuming the Zinc Coat acted as a zinc and disappeared quickly.

Ditto Here, this stusf works really well. Just make sure the metal is super clean and grease free prior to application, dry well pior to immersion in water, like 24 hours minimum in dry conditions.

PugetSound
02-17-2010, 09:29 PM
First off, painting CRES isn't quite the same as painting steel. For one thing, CRES requires waterflow to maintain it's corrosion resistant properties. Painting the prop will likely be a wasted effort due to cavitation and water erosion. I would NOT recommend powder coating unless it is done by someone who understands that the item is going into the water - powder coated items tend to have one spot that gets missed and requires touchup (that is, the place where they hang the item - the hanger acts as one electrode).

If you want the very best advice that your TAX DOLLARS have already paid for........................................ go to: www.NSTCenter.com this is a public access web site maintained by the US NAVY for general access by contractors. Do a search for "painting rudders" and I guarantee you'll find plenty of info - including case studies and pictures.

CJ
02-20-2010, 06:55 AM
Thanks, everyone, for the tips. The crew at my marina is pushing a product called "Propspeed", and according to the mfg, it "...has exceptional adhesion to all metals below the waterline and provides multi-season, foul-free running gear service!" Considering the cost, I asked how long a multi-season is, but no one could tell me.

Since this is far from a high performance vessel, maybe I'll look into the Petit Zinc Coat Barrier product that appears to have some success - it'll be better than nothing anyway...

Ned L. - as far as topside photos - since this boat is made of that other popular boat building material, I figured it would be better suited for another forum, but thanks for asking :D.

CJ

nedL
02-20-2010, 08:09 AM
Just because she is of the other stuff didn't stop me from asking. With an underbody like that, she's still got to have nice lines & be a good looking boat. - They're always welcome here. :)

CJ
02-20-2010, 02:33 PM
Okay, you talked me into it...
36' Calvin Beal, Jr.

http://i255.photobucket.com/albums/hh147/cjg0601/Fall2007CruiseFa.jpg?t=1266694033

BBSebens
02-20-2010, 07:06 PM
Well Im sure we all wish we could build every boat out of wood, but it just doesn't quite work that way does it?

Shes beautiful. good lines, nice cabin. Nice sturdy clean look to it. A good looking boat.

what does she have for power?

fellswoop76
02-22-2010, 04:39 PM
were those welds connecting the rudder to the stock pickled with acid?
they should be, or else you risk corrosion

CJ
02-24-2010, 01:51 AM
BBSebens: Thanks for asking, and for the compliments! She's got a 370 hp Yanmar (6LYASTP); again, far from a 'high performance' vessel - top speed of about 22 kts. But, I'm not in it for the speed... it's the journey, right? Oh, and even though this one isn't of wood, I have built a few woodies of my own which is what led me to this forum. If I could have built something like this, I probably would have but I haven't breached the 18 foot length limit yet...

fellswoop76: Pickled in acid? I could ask my boat builder, but I think I know the answer: "Did WHAT with acid?". I'd have to say no. There was just the typical post weld heat treatment to relieve the localized stresses caused by the weld, that's it. However, the welds look as good as they did in 2006 when she was launched, that is after I scrape away all the growth at the end of each season (which led me to my original question). But, thanks for putting the thought of my rudder falling off in my head for the upcoming season...:(

Anyway, I think I'll prime & paint my rudder & prop this year as a test. If it doesn't work out, I can always take off whatever's left next December.

Now, who has built an Ocean Pointer that can post some pictures??? That's the next project.

Thanks again,
CJ

mmd
02-24-2010, 09:44 AM
If the hydrodynamic action on the prop will erode the antifouling paint, it will erode the barnacle. It's the parts that don't get washed away that need the antifouling. So, paint the whole thing and don't worry about the bits that get washed off...

...but, make sure that the antifouling that you use is compatible with the rudder and prop materials.

fellswoop76
02-24-2010, 10:45 AM
if it was done by a boatbuilder, I'm sure he did it right. See the flux from the rod brings impurities to the surface, and if they are left, the weld is not protected from corrosion

nedL
02-24-2010, 12:38 PM
Beautiful CJ ! Thanks for posting her picture, very nice lines. (Bet you didn't know that Calvin's granddaughter & her husband live in Woodstock.) :)