Opportunity to remove hull-deck flange

<< First  < Prev   1   2   Next >  Last >> 
  • 21 Jan 2019 15:36
    Reply # 7013027 on 6980313

    It seems like a general consensus is building for keeping the flange, and capping it with wood - David's worksteps seem to make the most sense: Get some wood on top of the flange, then use the attachment of the bottom piece to add permanent mechanical fasteners, then cap it.  I think this would meet my desire to get rid of the rubber bumper, but still keep the existing structural integrity while sealing away potential leaks.

  • 17 Jan 2019 19:40
    Reply # 7007231 on 6980313

    What Len says makes sense to me and I had been thinking that cutting the flange off is possibly avoided by capping it with a s/steel U section, made by cutting square section stainlessteel tube(316grade) in half.

    This is then epoxy glued and fastened on, making a clamp like finishing trim piece that  will to some extent retain structural integrity of the join area.

    Later on, a wooden trim strip could be added.

    Last modified: 19 Jan 2019 20:42 | Anonymous member
  • 17 Jan 2019 16:19
    Reply # 7006708 on 7006301
    Scott Dufour wrote:

    My concern is not getting enough runout on the top of the joint.  There's not a lot of area to work in there, so the surface prep is also challenging.  The toe-rail in molded into the deck, creating a literal pain in the neck to get up underneath it.  Thoughts?

    I think it all comes down to "how much are you willing to spend?" Time, pain and money, yup, all those things. It sounds like you are able to trade time and pain for money if you are thinking of having someone else do the work. I am not sure only glassing the inside is a good idea if you are to cut down the flange to a point where the fastenings are removed. There is a gap between the two halves that is now filled with some sort of seal. The joint works by having the fastenings compress the sealer. If you use a wood rub rail you are using the wood in it's weakest orientation and so I don't think it can be trusted to add a lot of strength to the joint unless it is fastened from top to bottom. To do that the rub rail would have to be reasonably thick which is not the "look" you desire. Therefore the inside glassing would need to be as thick as the rest of the hull/deck as it would be doing pretty much the whole job.

    The more I think of just adding a wooden rub rail the less I like it. If the wood is only mechanically fastened and not bonded to become part of the hull, water will collect between the hull and the wood and rot from the inside where you can't see it. If there is any flex in the joint, the wood will crack along the grain. I think the cheap solution is to leave the joint as is and just change the rub rail for new material. I think the next step really is to completely replace the joint inside and out and fill any gap as well. The outside would certainly be the easier side to work on if you are refinishing anyway. I would not cut the flange off straight but cut it into a concave "V" as if you were filling a hole in the hull (which is really what you would be doing). If you are doing the outside without having already done the inside, you may need to do the outside in "stitches" or tacks so that the joint remains aligned (which would take longer and be more work).

    The person who gave their estimate has actually looked at your boat where none of us in this forum have done so. It is sometimes faster to completely remove a problem and replace with new rather than doing a fix. In this case I do not think the difference in materials used one way or the other is significant.

  • 17 Jan 2019 16:17
    Reply # 7006704 on 6980313

    You're right, Scott. I wouldn't fancy taking that on. I hadn't factored in that toerail.

    I think Annie's approach has the most going for it. This is what I would do:

    1. Clean the outside edges off a little, but not too near the bolts.
    2. Take the bolts out.
    3. Fit a piece of wood to the radius between the hull and flange, clamp it in place, drill down from the top, bond it on using temporary (waxed) bolts in some of the holes.
    4. Fit a piece of wood to the radius between the deck and flange, drill up from the bottom, counterbore all holes, bond it on with permanent bolts, bolt heads and nuts to be below the surface.
    5. Plug the holes and clean up.
    6. Fair up the outer edge, and bond on a thin strip of wood, using small temporary screws.
    7. Take out the screws and round off the corners.

    This would add a lot of strength and waterproofing, and would obviate the need to do anything inside (though I might fill up the groove with sealant, just for luck).

  • 17 Jan 2019 13:10
    Reply # 7006301 on 6980313

    Annie and David - those ideas could work - if I can be sure of getting enough strength from the interior glass.  My concern is not getting enough runout on the top of the joint.  There's not a lot of area to work in there, so the surface prep is also challenging.  The toe-rail in molded into the deck, creating a literal pain in the neck to get up underneath it.  Thoughts?




  • 15 Jan 2019 08:11
    Reply # 7001620 on 6980313

    You could grind, or whatever, the existing flange down to the width you've chosen. I'd glue a piece on top, clamping.  Then one underneath, ditto.  Plane to a fair curve and then glue and scew a capping (maybe zig zagging the screws above and below the flange).  Remove the screws so that if you damage the wood, you don't make matters worse by wrenching screws about.  Lots of ways to skin this cat.

    Have you done the sums on 35 hours labour?!

  • 14 Jan 2019 22:02
    Reply # 7001010 on 7000630
    Scott wrote:

    Annie: It will definitely get a wood rub rail added to replace the rubber bumper - I don't see how I could do the rail without grinding off the flange, though: the flange sticks out a good 1.5 inches from the hull, right at the top of the topsides.  A timber rail around all that would have to be really big.  Is there a way around that you were thinking?


    Cutting off most of the flange, leaving say 3/8" or 1/2" protruding, is doable without difficulty, once the inside has been well glassed. Grinding it down flush, without making too much of a mess that has then to be filled and faired, is a much bigger ask. Then a matching groove can be routered in a timber rail that is say 1" or 1 1/4" thick. This should give good vertical location and a fair sheer line. The rail would need enough vertical depth to get some fasteners into the hull, below the flange.
  • 14 Jan 2019 21:05
    Reply # 7000630 on 6980313

    Thank you for all the input, everyone.  I love the variety, and I'm mostly encouraged by the fact that nobody said that it's impossible.  David Tyler and David Thatcher came closest with, in essence, "It's doable, but is it worth the cost?"  

    Zane kinda nailed where I am on it - I really hate that rubber bumper, the filth that collects under it, the crappy way it's designed.  And unfortunately it's what I see when I look at the boat.

    The deck and hull are getting faired anyway from the other work and painting - so that's not really extra cash.  The builder estimated an extra 35 hours work to cut off the flange and glass it over. Either he or I will glass the interior side - which it sounds like we're all agreed should be done whether the external flange stays on or not. 

    Annie: It will definitely get a wood rub rail added to replace the rubber bumper - I don't see how I could do the rail without grinding off the flange, though: the flange sticks out a good 1.5 inches from the hull, right at the top of the topsides.  A timber rail around al that would have to be really big.  Is there a way around that you were thinking?

    Last modified: 14 Jan 2019 21:06 | Anonymous member
  • 03 Jan 2019 19:49
    Reply # 6982121 on 6980313
    I'd also use the hull/deck flange for the basis of a rubbing strake.  I'd glass along the joint on the inside.  Check the fastenings: Fantail's hull deck joint was held to gether with a horrid alloy rail, but had been temporarily secured with mild steel chipboard screws (which were too long and poked through, making a delightful hazard for probing fingers.  Most of them had corroded away, so I suppose that might have been the intention.)  Your builder may have used cheap stainless - out of sight, out of mind.  You could probably grind back a bit of the surplus flange along the outside.  Taking it off altogether is a big job that would mean a lot of fairing after the event.

    The rubber makes a practical, but ugly protection strip.  I'd go for wood, but please don't go for the 'scrubbed' look.  It hastens the weathering and is anyway and unattractive grey colour.  If you want a grey rubbing strake, I suggest you paint it that colour and incidentally protect the wood.  Personally, I'd choose a nice bright colour to show off the sheer and add a bit of personality.  For years I tried oils and varnishes of various types on Badger's rubbing strake.  An ocean crossing would see them disappear.  I then painted it green and that lasted.  Don't ask me why - the varnish never gave me any problems anywhere else.

  • 03 Jan 2019 07:28
    Reply # 6981159 on 6980313

    "If it ain't broke, don't fix it".

    Is the joint leaky or structurally weak? If it is, glass on the inside will fix it. If not, no need to waste time and money. If there's doubt, a little glass inside will give peace of mind.

    You don't like the rubber on the outside - fair enough, it's probably old and in poor condition, and ripe for replacement. A rubbing strip that stands proud of the topsides is generally a good thing anyway, to be sacrificial and save the rest of the topsides from scrapes if you have an argument with a dock wall. So I'd spend the money on replacing the rubber with iroko or other suitable and available hardwood. That will add strength, where the rubber doesn't. Leave it bare, or oil it.

<< First  < Prev   1   2   Next >  Last >> 
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

                                                              Site contents © the Junk Rig Association and/or individual authors

Powered by Wild Apricot Membership Software