Cove & bead planks / strips.

Discussion in 'Wooden Boat Building and Restoration' started by cyclops2, Oct 27, 2011.

  1. cyclops2
    Joined: Sep 2010
    Posts: 242
    Likes: 7, Points: 0, Legacy Rep: 94
    Location: New Jersy

    cyclops2 Senior Member

    I am drawn into using that setup on a boat this winter. It seems Like a table router & 2 bits are my Christmas presents.
    I like the fact that I can change thickness as needed & still easily blend all the boards.
    The almost 100% edge gluing is nice.

    What is the down side of cove & bead ?
     
  2. gonzo
    Joined: Aug 2002
    Posts: 14,735
    Likes: 756, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    The cost is the first drawback. If you have tight curves, when you fair the hull the glue lines will end up wavy. When you need to spile or add a cheater, it is rather complicated to do the bead and cove on the tapers.
    Square edge strip planking also gets 100% glue if that is the method you are using.
     
  3. sabahcat
    Joined: Dec 2008
    Posts: 792
    Likes: 27, Points: 0, Legacy Rep: 273
    Location: australia

    sabahcat Senior Member

    Big piles of expensive cedar/kiri/etc shavings on the floor
    Plus the time spent to put them there

    I too prefer square edge
     
  4. cyclops2
    Joined: Sep 2010
    Posts: 242
    Likes: 7, Points: 0, Legacy Rep: 94
    Location: New Jersy

    cyclops2 Senior Member

    Then why is it made & sold & used ?
     
  5. sabahcat
    Joined: Dec 2008
    Posts: 792
    Likes: 27, Points: 0, Legacy Rep: 273
    Location: australia

    sabahcat Senior Member

    Quite obvious isnt it?
    It uses more material, costs more and puts more money in the pockets of the suppliers.
     
  6. tunnels

    tunnels Previous Member

    Just set up a bench with 2 routers one bead and one to cove ! .You will find as you go round the bilge turns the bead and cove needs to shift a little on the plank edge to get the best possible location so this can be done by raising and lowering the routers little by little then eventually as the curve straightens the routers get slowly put back to there original setting . Plus as you shape the planks they can be done individually if ends are tappered . Its take just a little bit of imagination and thinking about Edge glueing !,.have to make sure all your timber is the same moisture content ! dri will tighten up ! damp will shrink and possibly split and tear planks apart so your choice :p:p
    Made a yacht plug a while back and we precoated all the 15mm sheets with a epoxy sealer coat both sides
     
  7. LP
    Joined: Jul 2005
    Posts: 1,414
    Likes: 57, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Bead and Cove, and more generally, strip-planking is just plane easy to do. And, if you are careful in your planking, you will get a nice, fair, rounded hull form. Any time you take big pieces of wood, turn them into small pieces of wood and reassemble them back into a large piece of wood, it going to cost time, money and materials. The amounts of each are determined by how much you do yourself and how much you spend to have someone else do it for you. From the sounds of it, your a do-it-your-selfer so your greatest investment will be your own time. Sometimes you can find good deals on cedar at the local lumberyard, especially at end of season. I have some that has been waiting for me to use now for 2-3 years.

    I think you will like the end product of your labors once you get there. The road to get to it may take a little longer than other methods, but you can produce a nicer hull over a method that uses sheet goods.

    Additionally, I too have gone with the squared strips as opposed to the bead and cove strips. If I were to build another strip hull, I would again use the squared strips, but I would consider beveling each new strip to match the previous with a hand plane. Bead and cove or planing, I think the net effort and result would be about the same. If it is a dry sailed boat, I would consider a waterproof/resistance wood glue in preference to dealing with a two-part glue. This being said, the single-part glue will not deal with gaps as readily as a thickened epoxy and bead and cove would typically assure this.

    Happy Building!
     
  8. cyclops2
    Joined: Sep 2010
    Posts: 242
    Likes: 7, Points: 0, Legacy Rep: 94
    Location: New Jersy

    cyclops2 Senior Member

    I thought the Cove & Bead DID AWAY with being able to match the 2 surface close enough for the expense of Epoxy & glass cloth? Plus eliminating the risk of Epoxy allergy?

    I have used Titebond II on everything wet with no delamination after soaking throughly dried glue.
    I do not build boats to sit in L of L boiling water.
     
  9. nordvindcrew
    Joined: Sep 2006
    Posts: 541
    Likes: 13, Points: 18, Legacy Rep: 231
    Location: Marshfield massachusetts usa

    nordvindcrew Senior Member

    bead and cove or square?

    I have about 2600 lineal feet of 5/16" X 1" western red cedar that will go into an 18 to 20' rowing boat for open water rowing. the problem is that the wood is of random lengths from 5' to 12'. If I bead and cove it will it be easier to build with than the square stock? It seems that to use square stock I would have to scarf it into continuous lengths. That would be almost as much work as doing the bead and cove. I'm not worried about glue lines or unfair strakes because the wood is colored from white to deep red which rules out bright finish. The finished boat will be painted inside and out. I got the wood for free and have already done all the preliminary sizing (5/16" X 1"). Suggestions on which way to go, and why.
     
  10. LP
    Joined: Jul 2005
    Posts: 1,414
    Likes: 57, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Cyclops,

    My statement might have been vague. Bead and cove does away with any gap problems and should ensure adequate adhesion with such a glue as Titebond II ot III. A dry sailed boat with a proper finish should work just fine.

    Nordvincrew,

    As a former trim carpenter, we used to sort or trim materials by color so that each door or window trim was matched to itself. With the house or even the same room, we would have color variations, but we made attempts to limit color variation in adjacent pieces. The really bad ones we hid inside of closets or pantries. My point though, if you are interested in a bright hull, is to sort your wood by common colors and devise a scheme or pattern. I did this on a 16' sailer. Over time the color variations diminished, but a little bit of the pattern remains. I did a couple of dark lines. One at the sheer and one several planks down. I tried to do a shaded transition to light, then back to dark. Then below the second dark line, I started with my light planks and transitioned to dark at the bilge. Here is a photo. The shadings just aren't real significant, now.

    RGS_5483small.JPG

    The worst offenders could be hidden below the waterline.

    I did my scarfing "on-the-fly". I set up an 8 to 1 scarf jig on my radial arm and cut the scarf as I was installing the planks. Each joint got an additional nail near each end of the scarf. When the radial arm saw went belly-up, I went to a 45 degree cut instead of the 8-1 scarf. I drove a nail through the 45 to stabilize it until the glue cured. I found the 45 degree cuts to be more pleasing visually. If you stagger your joints, you could use butt joints and have all of the strenght that you need.
     
  11. nordvindcrew
    Joined: Sep 2006
    Posts: 541
    Likes: 13, Points: 18, Legacy Rep: 231
    Location: Marshfield massachusetts usa

    nordvindcrew Senior Member

    bright finish

    Even if I could go bright, I'd still paint the boat, just like it better that way. I'd just as soon not bead and cove if it works well to go with square edge strips. Planing a bevel doesn't seem too bad. I read that keeping the strips aligned can be a problem. Do they tend to squirm in and out and does it make for more work fairing the hull? My wood (free) is not of the highest quality, it does have some smalll knots. The boat will get rough use so i plan to use a much heavier weight fiberglass than normal; probably 12 ounce inside and out with 2 layers on the bottom. Is epoxey absolutley necessary, would vinylester or polyester be satisfaqctory. I don't want to cheap out, but would like to save money if possible (retired and on a fixed income) We beach on rocky shores and occasionally slide up and over submerged rocks. A rugged hull is absolutely necessary, while light weight is not a concern. Our best boat is a 19' Jersey Skiff that weighs well over 200 pounds. we have rowed it 21 miles in less than 4 hours. Light isn't our priority. strength and seakeeping ability are number one
     
  12. LP
    Joined: Jul 2005
    Posts: 1,414
    Likes: 57, Points: 58, Legacy Rep: 584
    Location: 26 36.9 N, 82 07.3 W

    LP Flying Boatman

    Bright is not for everyone and paint provides better UV protection.

    Someone else can answer vinylester/polyester question. I believe, though, that you can do it. The quality of adhesion is going to rely on your preparation of the wood surface. If you use multiple layers of fabric, I think that you have to layer mat in between(w/ Poly & Vinyl). This is to your benefit as it builds additional thickness and more abrasion resistance.
     
    Last edited: Oct 28, 2011
  13. cthippo
    Joined: Sep 2010
    Posts: 775
    Likes: 39, Points: 28, Legacy Rep: 465
    Location: Bellingham WA

    cthippo Senior Member


    I went down that road building the Raptor and it was a disaster. The scarf joints weren't strong enough to survive the bending around the shape of the hull. PAR suggested affixing the strips to the strongback and then attaching the scarfed ends together which is what I did and it worked great. Gluing each strip to the one next to it means that the stress of the bend is distributed over a larger area of glue and so the force isn't concentrated all at the joint.
     
  14. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 477, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Bead and cove bits make an easy planking method easier, at the cost of a fair bit of planking stock on the floor and some interesting fitment issuers. Having used both square and cove edges planks, I'll continue with square, just to save the trouble of all that milling. A quick pass of two with a small plane, can easily make square edged stock fit very nicely and there's more zen about it too.
     

  15. gonzo
    Joined: Aug 2002
    Posts: 14,735
    Likes: 756, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    There is no need to scarf planks. They are thin enough that the planks on either side of the scarf act like a butt block.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.