Need a non-adhesive sealant.

Discussion in 'Materials' started by fallguy, Aug 22, 2020.

  1. fallguy
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    fallguy Senior Member

    AB5AF9D3-3D0F-4339-B84A-81624A901893.jpeg
    I'm the big guy in the cafeteria and if you pick on Richard, you've picked on me. Plus, 'ask the designer' is such an annoying default.

    What in God's name is so hard to understand? I have a gritty personality from the last month of fairing my boat and the last day of sanding was today at 320 grit. I'd say I'm just fine! Except my back is having infrequent spasm that wraps around my chest from the torture board which feels like a heart attack, but isn't. I just double over and go to the ground for a bit. Alcohol seems to actually help a bit.

    Crickeys, can't a collective bunch of gents come up with some kind of silly putty and call it good? Crickeys is for Brendan and his all caps shot.

    The beam goes into a glass socket that is about 0.125" larger all around, but there is a silencer that goes in two places where two 14" long bolts go through. The bolts are just through the beam and bolted across the socket and a bulkhead. That beam is the seat for the cabin aft half. The bolts are 316, so any salts getting in there bother me. There are 5 other rivnuts also 316 in the beam. Best to keep the water out.

    I tape the silencing on with duct tape, but any H2O that gets in would find its was back around into the section and into the crevices around the silencing.

    Now that I have polished things here to 60 grit, hope it makes more sense.

    This thread could have been closed after the duct seal comment. That stuff is ideal for caulking a two sided bond open crack. It'll go up to like a full inch as well.

    I am going to freshwater first. I think. So had no plan to paint the beams. If or when we go salty and we hope to at some point; I would need to alodine a/o paint the beams. Now, all of you guys saying don't bother sealing are going to jump up and down and shout I was right. Please link the video.

    Here in Minnesota, water sitting in places freezes and growz. And it busts things, so we do all we can to prevent it from ingress.

    A common one is a trim pump. Once the trim pump seal goes; any bit of water gets sucked in and the trim pumps grow inside. So, we just avoid water ingress here like the plague. It is frozen here nearly 6 months of the year. The mean temperature of Lake Superior where I might end up is 39F. Today is late summer and mid lake surface temps are likely in the 40-50 range. The season is short. To complicate things, some places get 10 feet of snow. This is too much for most boat cabin roofs. I suppose I should have asked Richard to design for that, too, eh? Nah.

    Rumars-sealing the beam/socket interface only. Duct seal is a good choice. I can keep a chunk onboard and double bag it.

    I have to go do some vacuuming now.

    I'll share a picture of the boat here in the next month that should be entertaining.

    Above pic is prior to hours of sanding today.
     
  2. upchurchmr
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    upchurchmr Senior Member

    What is silencing material?

    Does your verbal description mean that the beam does not rest on the bottom of the socket? (.125 all around gap).

    Nice of you to continually leave another bread crumb trail to the solution you would like us to come to.

    Now it's freezing water in addition to corrosion.

    Any other requirements?

    Since you only said you were in the USA that didn't provide a clue.
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    As soon as silicone was debarred, it became a little difficult.
     
  4. fallguy
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    fallguy Senior Member

    Of course, as soon as you ask for something simple and easy; it becomes more difficult quickly.

    I asked for a non-adhesive (low adhesive) sealant.

    Duct seal is a great answer. I might have considered and rejected it already because I figured there must be something in a caulk tube.

    Most of the rest of the details and information and questions are irrelevant. I have the utmost respect for Barry and am grateful for his comments. This is a boat designed for ocean cruising that might get stuck on a freshwater sea. It changes little other than I don't need to worry about aluminum corrosion as much.

    Thanks to everyone. I am having a rough time with my back which might have me edgy.
     
  5. brendan gardam
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    brendan gardam Senior Member

    what do you mean, i don't have any posts on this thread. :p
     
  6. Barry
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    Barry Senior Member

    Can anyone send Fallguy electronically ABYC TE-4, the technical report on lightening protection?
     
  7. SamSam
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    SamSam Senior Member

  8. fallguy
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    fallguy Senior Member

  9. Mr Efficiency
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    Mr Efficiency Senior Member

    Anything that "doesn't stick" is suspect of encouraging infiltration of water. You might look at some kind of material that is semi-solid at normal temps, but melts away at moderate heat, that could be achieved by heating the aluminum beam with a heat gun.
     
    fallguy likes this.
  10. kapnD
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    kapnD Senior Member

    I know it’s irrelevant to your question, but if water intrusion is going to be so problematic, why not put a drain at bottom center? If the beam is sealed in, any water intrusion will be trapped.
     
  11. fallguy
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    fallguy Senior Member

    Like what?
     
  12. fallguy
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    fallguy Senior Member

    This is a potentially wise idea. The only issue is it would also be an entrance unless you closed it.

    I can tell you today I went out to check on whether any rain had blown in and sure as heck star hull blind socket has water and it is realy stinky! Some organic stuff like a bug gets in there and kicks off. Sealant is best.
     
  13. Mr Efficiency
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    Mr Efficiency Senior Member

    Something in the wax family, perhaps. But like I say, the right coating (like 2 pack PU with a compatible etch primer) will effectively seal the metal off from poultice corrosion. You can fill the gap with something that isn't adhesive to any substantial degree, if you want that, so you can dismantle it if required.
     
  14. Blueknarr
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    Blueknarr Senior Member


    It might take a few few or maybe many experiments to get the ratios right. Melt together parifin, bee's, and the previously mentioned plumber's waxes
     

  15. SamSam
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    SamSam Senior Member

    I just noticed that, my bad.
     
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