Prop coating for anti corrosion and fouling?

Discussion in 'Props' started by DennisRB, Mar 13, 2016.

  1. DennisRB
    Joined: Sep 2004
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    Location: Brisbane

    DennisRB Senior Member

    Hello, I am about to get one of my volvo folding props back after a new hub got installed after ongoing corrosions issues. I also have aluminium fixed blade props as spares which I will need to put on the other engine while the hub is repaired on that. The fixed blades do not corrode at any abnormal rate even though they have no anodes and the folders do.

    I want to coat these props with something to prevent corrosion as a number one and prevent fouling as a number 2. The folding props suffer from severe corrosion issues. I thought a coating to minimise the bronze to sea water contact area would reduce electrolysis. And while I can I want to strip all the old paints off the fixed blades and re do that too.

    What products can I use on these bronze and aluminium props? What surface prep should I do beforehand? Can I just use 3 coats of regular epoxy after a sand blast then apply hard antifoul (suitable for sail drive legs) on that?

    I have 4 props to do. Would prop speed be too expensive? Or is this stuff good?
     
  2. CDK
    Joined: Aug 2007
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    Location: Adriatic sea

    CDK retired engineer

    Against corrosion any coating will help; at least if you succeed in obtaining a strong bond to the metal surface. My own experiences with epoxy in seawater are a bit disappointing, I prefer something more flexible like polyurethane.

    I've tried many antifouling coatings, including the overly expensive special products for props that promise a Teflon surface with almost zero friction. In my opinion it is a waste of time and money.
     
  3. DennisRB
    Joined: Sep 2004
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    Location: Brisbane

    DennisRB Senior Member

    Thanks. So which product do you recommend? last time I used a regular spray can etch primer and it cane off the bronze in a few weeks. I thought laminating epoxy as a base coat would seal it well and stick to a sandblast finish.
     
  4. waikikin
    Joined: Jan 2006
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    waikikin Senior Member

    I've got Propspeed on my Carters prop, coming up on two years(19 months) & just knocked a couple of barnacles off a week ago, got it at work on an Arvor 20 as well, seems ok on that, not sure it does anything for corrosion, both those props are bronze. There's really nothing to lose using your epoxy scheme, how about documenting how it goes so we all learn something.

    Jeff.
     
  5. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    The best way to stop the corroson is to tilt the unit up out so the props are not in sea water 100% of their life.
     

  6. DennisRB
    Joined: Sep 2004
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    Location: Brisbane

    DennisRB Senior Member

    This is on a saildrive leg on a sailing catamaran.
     
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