Thistle Class Forum

Replacing Stainless Steel Fasteners

Home Forums Thistle Rigging, Repair, Maintenance, & Trailering Rigging Replacing Stainless Steel Fasteners

Viewing 5 reply threads
  • Author
    Posts
    • #2005139
      John Howell
      Participant

      I am rerigging 3849 after removing all hardware to redo the brightwork.  As I am doing this I am replaceing all of the fasteners, many of which may be Doug’s original material from 1991.

      https://www.thistleclass.com/wp-content/uploads/hm_bbpui/2005139/av8r7kmhqpdpy9meb2cypo900ljvx38f.jpg

      These are the four 1/4 SS machine screws that held the lifting rings on the forward grating.  You can see that the third ms had corroded through.  The corrosion occurred where the ss was in contact with mahogany.  Note that these were pulled out of the boat in June 2020. The months earlier the boat was being lifted on these bolts.

      I have since learned that mahogany has a pH below 7 and is reactive with different materials.

      The material failure above is the worst example I have seen but many of the fasteners show signs of corrosion.  The lesson here is check fasteners every one of two years.  Fasteners are cheaper and easier to replace than repairing your boat.

       

       

       

    • #2005153
      David Morris
      Participant

      I suppose bedding fasteners w/ Silcaflex or even silicon would help.

    • #2005193
      Kevin ArrowKevin Arrow
      Participant

      Makes you wonder what the fasteners for other high tension areas look like.   Chain plates, Highfield lever, vang etc.

       

       

    • #2005194
      John Howell
      Participant

      Kevin, you are so right.  This caused me remove ALL fasteners when I pulled the hardware.  Any fastener showing signs of corrosion was replaced.  All high load attachments were replaced, regardless.  Also, on all high load areas, I drilled out the wood until I had clean wood (sometimes 1/4″ diameter, sometimes 3/8″ diameter.  I filled all the holes with a putty of west epoxy and 406 filler.  Then I re-drilled holes in the epoxy to reset the hardware.

      I have replaced my lifting eyes with Dynema soft shackles made with 3/8″ dynema and my vang is attached to my stantions with 1/4″ dynema soft shackles which loop through holes in the FRONT of my stantions.  This means I have 5″ of wood holding the vang.  I watch the soft shackles for sings of wear and replace when necessary.

    • #2005214
      PETER HALEPETER HALE
      Participant

      I have always made it a point to check all the ss fasteners in #3898 every 2 to 3 years, usually when I am varnishing the mahogany.   Never noticed any issues with the bolts on the lifting rings, but have found numerous issues with other ss bolts and screws over the past 25 years.

    • #2005229
      David Morris
      Participant

      Where to buy quality stainless for such fastenings? I have been shocked a few times in recent years regarding the brittleness of the screws I have been installing,….particularly those that come from the “big-box stores”. I just don’t have confidence when I can torque the head off of a screw using a standard handheld screw driver. And super frustrating when the screw in embeded, but you give it the last little torque and turn and the head snaps off.  Forgetaboutit if you are using a power driver. I think the metal is just inferior. Any material science geeks out there?

Viewing 5 reply threads
  • You must be logged in to reply to this topic.