Ideas or help on install of hardwood sole in 14' alum. boat

Discussion in 'Boat Design' started by WinnMann, May 22, 2015.

  1. WinnMann
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    WinnMann Junior Member

  2. alan white
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    alan white Senior Member

    I meant the sections of cleated-together wood set into the hull and aren't attached per se, though you can certainly fasten the sections using turn buttons or toggles, etc..
    The wood could certainly be pine, hopefully having small knots or clear.
    I know cedar can be expensive but it's the top choice. It doesn't check easily and it resists rot. It's also light and good looking. Look around but not at box stores. There should be a lot of cedar available in Michigan. Try small wood mills and local timber dealers who have dry wood and planing facilities. They can mill the wood to the desired dimensions.
    I would imagine that plywood would also be expensive. It wouldn't save much. You could of course use cheap plywood and carpeting and save a bit but you've got contact cement and maybe epoxy and if the plywood is pressure-treated can you get thinner 3/8", e.g.? I've seen 3/4" but maybe 3/8" and 1/2" can't be sourced too easily.
    Un pressure-treated plywood won't dry out enough to prevent mold/rot underneath so it has to be epoxied---- and now you're into money again.
     
  3. WinnMann
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    WinnMann Junior Member

    Great ideas, I'm going to call around Monday and see what I can find. Cedar does sound much more attractive than pine, so hopefully I can source something more reasonably priced. Thanks!
     
  4. WinnMann
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    WinnMann Junior Member

    I called around this morning to 10 places until a I found a place with reasonable prices. It was about $6 for a 1x4x8 and i got 22 of those and a couple of 10 footers just to have some extra if need be and also to most likely build the tops to the bench seats that go in the middle of the boat that were rotted out as well. Out the door it was about $170. I'm glad I listened to your advice AW, the wood is beautiful and light. I can't wait to see it when it's done. I'll be sure to post some pictures of her when shes finished. I'm debating on planning the boards down to a smaller size from 7/8" to 5/8" or maybe 1/2". The reason being because when the boards are cleated with another 1x4 or 1x2 underneath it makes for a very tight fight underneath the first bench. I also got some green extruded foam board to fit under and a pack of bronze screws. I really want to keep that natural look that the cedar has and not hide it by painting over it. What would you recommend to use bring the natural beauty out of these boards? A couple coats of a clear polyurethane, or something else? Thanks
     
  5. alan white
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    alan white Senior Member

    Try Cetol at about $36.00 per quart (do all surfaces before assembly of the wood parts). It really looks fantastic and is many times easier than varnish and it is easily recoated later on. Several "colors" available.
    By all means plane the wood down. The thinner the better so long as it will bear the weight of people walking on it. Try 1/2" if the spans are under 12" or so. Like I said, position cleats at half-span. They won't interfere with the frames underneath that way either and the sole will be stiffer for it.
    Sprinkle non-skid (crushed walnut shells or clean sand) on between first and second coats of (Cetol) like:
    Sand to 180 grit random orbital, wipe and tack-cloth and one coat of Cetol, then sprinkle non-skid on top surface, then two more coats of Cetol everywhere. Add coats each season as required. After a few seasons, renew non-skid. This will last a long time.
    That is a good deal on the cedar. About $3.00 a board foot.
    Don't plane the cleats under 3/4". There you want some beef.
     
  6. WinnMann
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    WinnMann Junior Member

    Okay Cetol looks great I'm going to try to find a local dealer here tomorrow. I'm going to follow your recommendations on the boards as well and plane them to down to 1/2" and the cleats to 3/4". I'll make sure to prep them as you say. I'm not sure I understand what you mean by positioning the cleats at half-span and that they wont interfere with the frame underneath. I'm thinking half span means the cleat would go about 4' down on the slat if it was an 8' slat, and probably one on each end as well is my thinking. Than the cleats would just set on the stringers like the original plywood did. I have a feeling I may be off here though.
     
  7. alan white
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    alan white Senior Member

    I am beginning to see what you're up against. You need to build a series of "floors" or flat surfaces to support the new cedar sole sections. The pieces you install must be attached to the longitudinal "stringers" that go fore and aft. They must be able to handle wetness so as not to rot. I suggest pressure treated wood laying across (side to side) the longitudinal stringers. I think pressure-treated 1 1/2" x 1 1/2" pieces would work. Attach them atop but not between the stringers with a single 1/4" machine screw/nut. Use stainless or (ideally) aluminum if you can source them. Space the cleats to lie halfway between these PT frames. They'll miss the PT floors and spread loads better.
    The sole will be 1 1/2" higher but that shouldn't bother.
    I don't like the idea of foam underneath. If you wish to add flotation, put it elsewhere if possible. Paint or caulk the PT wood where in contact with aluminum. Modern PT wood eats aluminum for lunch.
     
  8. WinnMann
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    WinnMann Junior Member

    Alright I'm going to return the foam and buy some PT wood. The benches have foam in there and so do the seat and livewell that go in the middle so I hope that's enough. I'm going to lay the PT wood athwartship than mount it with 1/4" SS machine screws to the stringers that the original plywood was attached to. I have a question about the cleats. Are they now to be the same thickness as the PT "floors" which are 1 1/2" so the floor is level? Just making sure I'm understanding this right. How far apart do you think I should lay the "floors" apart, maybe 2'? The only problem I'm seeing with this plan is the clearance between the stringers and the rear bench is about 1 3/4". So with 1 1/2" taken up for the PT "floor", and the 1/2" added on top from the slat, there'd be no room to fit the slat under there. Is making the "floors" an 1" x 1 1/2" or an 1 1/4" x 1 1/2" a viable option do you think? So the slat will fit under the bench.
     
    Last edited: Jun 1, 2015
  9. alan white
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    alan white Senior Member

    We're getting into some deep details. Cleats only hold the sole planks together. If you install crossing 1 1/2" x 1 1/2"s above the level of the longitudinal stringers I suppose you can have any spacing you desire. Therefore, to save weight, why not "let in" the floors so that they have greater depth, say 2 1/4" vert. dimension and 1 1/4" horiz. dimension? They would drop down lower than the stringers but still would be 1 1/2" above the original sole height.
    This would make them stiffer. Then try this: 5/8" cedar 3 1/2"- 4 1/2" wide and cleated with 2" wide x 3/4" thick cedar, clench-nailed as discussed (two nails each). Spacing? Both the PT traversing frames and the cleat frames would be 18" apart with 9" between alternating frame-cleat-frame-cleat, etc.. So the cleats would fall halfway (half-span) between the PT frames. The spacing of the aluminum ribs on the bottom doesn't matter.
    Regarding the bench. Only put the new sole where it isn't under anything. I can show you how to treat that problem if you supply some pictures.
     
  10. WinnMann
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    WinnMann Junior Member

    First off, I really appreciate you taking the time to help me out. I know that I'm asking a lot and that your spending a lot of your precious time helping me, and I just want you to know it is very much appreciated. More people like yourself would make this world a better place. Back to the problem at hand, I'm going to the store tomorrow to purchase some PT wood and get the ball rolling on this project. I'll be sure to post some pictures to make sure we're on the same page. I was imagining running the plywood boards from one side of the boat to the other (wall to wall) over the stringers. By letting them in do you mean to cut a notch in them at the stringers so that they drop in 3/4" and rest a 1 1/2" above the stringers? Also the darn half-bench seats that rivet to the middle of the boat would be sitting 2 1/8" higher than the original sole, because the 1 1/2" PT plywood and the 5/8" cedar slat sitting on top of that. I'm thinking that may change the angle of the half-benches at where they mount to the sides of the boat and may push them out a little bit. Do you think this couple of inches of change is negligible or should I change something? Lastly, clench-nailing is a totally new technique to me that I'm not familiar with, is there a reason I should "clinch" vs screwing? If so, I will definitely familiarize myself with this technique of fastening. And are bronze boat nails available only at a marine store or do I need to order them online? Sorry if you feel like your explaining this to a second grader, I tend to over think things sometimes. And great idea on skipping the sole on the rear bench, that thought didn't occur to me.
     
  11. alan white
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    alan white Senior Member

    Yeah, notch them 3/4" to end up 1 1/2" above the stringers. 1 3/8" above the original plywood if it was 3/4" thick. Make sections that are notched around the seat supports. Allow them to pass through to the stringers. Work around them. Never trap the sole so that you can't remove the sections to get at the bilge. The boat originally had no access and you see the result. Do a careful job and you'll smile every time you walk barefoot on that sole.
    Nails are cheap and when the cleat isn't very thick, a screw wouldn't be a good choice. Screws would easily split the cedar and should never pass through. You nail through using a nail about a half inch longer than the double thickness of wood. That would be about 2". With the overturned section lying on a piece of hardwood to buck the nail, bend it sideways (but not with the grain which can split the cleat) and hammer it flat. Very basic.
     
  12. WinnMann
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    WinnMann Junior Member

    Wow, your last post really cleared up a lot of confusion for me.I was really confused on how to lay the floors around the benches, while also keeping them removable, but you cleared that right up. The original floor was 1/2". I'm thinking of running a 1/2" board across the stringers to mount the seats to the floor. It would have to be about 18" to act as a floor to one of the benches and overhang a little to mount the livewell. I provided pictures just to clarify. All those boards would be 1 piece of 12" plywood by about 18". Do you think this is what I should do? I've been researching how to paint the PT floors and it looks like I should use a primer for PT wood and a latex paint and that I'm also supposed to wait a few months for the wood to dry before painting or the paint may not stick. I'm wondering if I should just use regular plywood or osb because of this reason and seal them some way to avoid rot, and also the PT wood seemed pretty heavy. I'm also trying to find where to buy the bronze boat nails, their looking to be kind of hard to source in my little town.
     

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  13. alan white
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    alan white Senior Member

    Boat nails can be ordered. A smooth shank is better for clenching. Not ringed shank which is for attaching by regular nailing where the grain will hold the nail rather than the bent end. Go online to find the nails and have them shipped. Drilling is recommended with the copper smooth nails due to 1/8" diameter.
    Try Hamilton Marine in Maine or Jamestown Distributors. Jamestown Distributors has them as item #NCCIIX (6d common). You can use those nails with roves (washers) which are slipped onto the nail after driving it and then clipped allowing a portion of the shank to be peened over (mashed into a lump to prevent passing back through the washer)-- look it up. Nicer looking, very shippy. Very easy. Probably 2 nails per board width.
     
  14. rasorinc
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    rasorinc Senior Member

    Glen-L site also has copper boat nails $15.00 a pound.
     

  15. WinnMann
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    WinnMann Junior Member

    I agree, I need to be more careful with the terminology I use, and I'm going to try my best to improve here on out.
    That fastening method is really smooth and strong looking. I just can't believe the price of the copper roves part #NCRV10/11 which is $27! With the copper nails, and roves and shipping it comes out to $52 which I was not expecting. Will the Burrs do the job just as well? The most expensive burrs on there is $4.61, compared to the $27 but than they seem to be out of stock of the burrs that would fit a 6d penny size #11 gauge nail. Also, I'm going to search around and find me some dry plywood per your instructions.
     
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