Prop dezincification

[webcraft]

When we were out of the water a month ago I noticed a pinkish tinge to our 3 year old prop and a bit of a dull sound when tapped. I blamed myself for not having fitted a shaft zinc when the prop was fitted 33 months ago, and duly fitted one.

We then had to lift out a month later, a month we spent in a marina hooked up to shorepower. To my horror, about a third of the shaft zinc is gone in a month. I will replace it before we relaunch, ideally with a slightly meatier one, but is there anything else I can do to preserve the life of the prop?

— W

 

[Tranona]

Paint it to reduce the surface area. Add a hull anode.

 

[Graham376]

Galvanic isolator?

 

[Nina Lucia]

When we were out of the water a month ago I noticed a pinkish tinge to our 3 year old prop and a bit of a dull sound when tapped. I blamed myself for not having fitted a shaft zinc when the prop was fitted 33 months ago, and duly fitted one.

We then had to lift out a month later, a month we spent in a marina hooked up to shorepower. To my horror, about a third of the shaft zinc is gone in a month. I will replace it before we relaunch, ideally with a slightly meatier one, but is there anything else I can do to preserve the life of the prop?

— W

Same here, we were advised to replace it, I don't think it's repairable.

 

[Aquanaught]

Unplug shore power when not on the boat.

 

[alahol2]

Hammerite special metals primer. Stays put, smooth finish, almost totally eliminates galvanic activity at least on the painted parts.

 

[webcraft]

Hammerite special metals primer. Stays put, smooth finish, almost totally eliminates galvanic activity at least on the painted parts.

That looks like a very handy tip. Does it stay on a whirling prop and stop fouling on a stationary one as well?

- W

 

[webcraft]

Galvanic isolator?

Ordered one.

- W

 

[alahol2]

That looks like a very handy tip. Does it stay on a whirling prop and stop fouling on a stationary one as well?

- W

It stays on the prop but it doesn't really stop fouling. If you put a coat of antifouling over the top then you've more of a chance of reducing fouling.

 

[vyv_cox]

That looks like a very handy tip. Does it stay on a whirling prop and stop fouling on a stationary one as well?

- W

See Propeller antifouling with Velox

 

[Beneteau381]

That looks like a very handy tip. Does it stay on a whirling prop and stop fouling on a stationary one as well?

- W

Only prob, I’ve looked everywhere on the Algarve for the special hammerite primer, it’s made of unobtainium!

 

[Graham376]

I got small tins of prop antifoul and it's primer from Ayamar at Ayamonte, can't remember the makes though. Sergio Roque hardware shop behind Faro market may stock Hammerite.

 

[Ceejay]

I used the Hammerite metal primer on my prop for the first time last year and applied Trilux Prop-O-Drev antifouling, having noticed small patches of de-colouration developing. At lift out for the Winter the jetwash removed almost all of the antifoul and beneath the primer was intact and no sign of the usual barnacles. A quick light rub with P600 paper and re-application of Prop-O-Drev and it’s good to go again. Wish I’d known about it years ago.

 

[Medway Matt]

I used the Hammerite metal primer on my prop for the first time last year and applied Trilux Prop-O-Drev antifouling, having noticed small patches of de-colouration developing. At lift out for the Winter the jetwash removed almost all of the antifoul and beneath the primer was intact and no sign of the usual barnacles. A quick light rub with P600 paper and re-View attachment 191958View attachment 191957application of Prop-O-Drev and it’s good to go again. Wish I’d known about it years ago.

How effective do you find Prop-O-Drev? We tried it a couple of seasons ago and it seemed to attract barnacles if anything. So far we've had best results with Hempel Hard Racing af, it lasts just long enough to keep the barnies at bay.

 

[Ceejay]

How effective do you find Prop-O-Drev? We tried it a couple of seasons ago and it seemed to attract barnacles if anything. So far we've had best results with Hempel Hard Racing af, it lasts just long enough to keep the barnies at bay.

Unlike previous years I had no barnacles at all, and the Hammerite primer was intact.

 

[Medway Matt]

Unlike previous years I had no barnacles at all, and the Hammerite primer was intact.

Thanks Ceejay. We've decided to give it a go again, seeing as it's designed for the job it should work, or at least be better than most alternatives.