Silicon bronze fasteners with SS parts

Discussion in 'Materials' started by MJT, Jul 2, 2020.

  1. MJT
    Joined: Jul 2012
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    MJT Junior Member

    Hi All:

    I'm about to put the hardware back on my wooden masts. Much of the hardware is stainless steel, and I'm wondering if there's a reason to avoid using silicon-bronze fasteners.

    Example: Silicon bronze fasteners in stainless cleats or winches
  2. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    Is it possible that some of your hardware could be chrome plated bronze, rather than stainless steel?
  3. hoytedow
    Joined: Sep 2009
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    hoytedow Carbon Based Life Form

    I would use stainless steel fasteners for attaching stainless fittings and bronze fasteners for attaching bronze fittings.
  4. trip the light fandango
    Joined: Apr 2018
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    trip the light fandango Senior Member

    The galvanic scale is why you need to stick to like as hoytedow says. Strangely the silicone bronze is more likely to react and lose integrity before the 316 stainless even though it is higher up the scale, I suppose it is because the stainless is harder?? I must have that wrong. So I checked the galvanic scale and the difference means your fastenings will go before the 316 stainless. If you are careful and use something with an insulating property like plastic washers and or the right grease, they may outlast you.
    Last edited: Jul 5, 2020
  5. sdowney717
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    sdowney717 Senior Member

    only downside with ss is crevice corrosion, in all other aspects superior to bronze. IMO. up on a mast that kind of corrosion is less likely as it is not constantly wet.
    if the bronze bolts and whatnot are in good shape, keep using them.
    Will Gilmore likes this.
  6. TeddyDiver
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    TeddyDiver Gollywobbler

  7. Will Gilmore
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    Will Gilmore Senior Member

  8. MJT
    Joined: Jul 2012
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    MJT Junior Member


    Thanks all for the replies.

    What bedding compound, if any, is recommended for screws in wooden spars? I've used Dolphinite.

  9. Rob Lehmann
    Joined: Feb 2021
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    Location: Newport, RI

    Rob Lehmann New Member

    For alloys that are commonly used on boats, and for use in a seawater (or any water for that matter) environment, here is a good galvanic chart to refer to. 316 Stainless and Silicon Bronze shouldn't be in contact.
    hoytedow likes this.
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