Traditional skiff help needed. Large Monk Skiff

Discussion in 'Wooden Boat Building and Restoration' started by Quartersawn, Jan 15, 2011.

  1. Quartersawn
    Joined: Jan 2011
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    Location: Cape Cod

    Quartersawn Going old School!

    Hi, I am new to this forum and I am on my second build. The first was a stitch and glue row boat very nice and well used. now I need a boat for a small 2-3 hp engine. Hoping to get an old Elgin for her. I found my boat to build and have collected the wood for it. Quarter sawn oak frames and wide cvg Cedar planks. Straight grain teak Knees etc.. only the finest I could find because this build is special to me. As a kid I grew up using boats like this one and at that time they were 40 plus years old and still going strong. well used in the local mashes where we would collect Scollops, Clams even tossed a few crab traps. These boats are tough work boats and we used them hard. In the spring we would take them to the marsh and sink them for about a week or longer to get em swelled up. It was a tidal area so we would have to put some bricks in them to keep em down and tie them up so we wont lose them to the tide. It was tough because some good citizen would pull them out of the water for us and flip them upside down on the beach, then we would have to sink em again. I had to go to the marsh right after school to check on them each day to make sure they stayed under. Thanks good citizen. I hate bailing!

    Anyways I have studied the plans thoroughly duplicated them in cad and built scale model following the building methods, it was tough to cut a dory plank on 1/8th inch planks but i did it. I am not a model builder so please be kind with my construction. only did it to study the build.
    It all goes together perfectly but I don't understand a couple of things. I have included some drawings to help you understand my questions.
    what's the best screw pattern for the bottom planks? into the cross frame or the frame bottom, I have screws coming in from side planks and Bottom see picture please, Also do i need to use cotton on the bottom planks with the newer 3m polyurethane caulking that are available? I will bevel the bottom planks to 3/16" what moisture level should the planks be when installed? Can I use Caulking where the planks attach to the stem? also where the Bottom planks meet the side planks and transom. I will use a thin strand of cotton here for sure. I want to glue the dory lap and was planing on using polyurethane glue,is this a good choice? It's the only place except the transom glue will be used on this boat. and that brings me to my transom wood choice if it is Ok by you Guys. I have to large solid mahogany planks 3/4 inch thick 22 inch wide and 47 inch long, Yes this is vintage stuff but it is plain sawn, very light wood almost equal to the spruce you can buy today in weight. I want epoxy wood flour glue them together for a one piece transom see picture, can this be done and still have a decent product to hold fasteners and if so what's the best grain direction to keep them straight when swelled. and for now the final question. I am not sure how to build the rear seat cross brace. do i fasten it to the stringer ends and put a brace in the center, see diagram, please note the model does not have the center seat braces or knees. i hope to find an old School guy here on the forum who can guide me along through the build this spring. thanks....
     

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  2. michael pierzga
    Joined: Dec 2008
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    michael pierzga Senior Member

    Is it a fore and aft, cross plank ? or herringbone bottom ? Does it have a Stout inner keel with an outerkeel cap ?

    The cross planked flat bottom skiffs I had as a kid were caulked pine or cedar , fastened to a robust keel and chine logs.....no frames in the boat... bottom planks only fastened to chine log and to keel.
    The chine logs were also two piece...inside chine and outside chine cap. The skiffs were Smooth, Naked on the inside...no paint...and they lasted year after year .

    Perhaps you could use a 5200 style bottom seam. Remember the sun hits the inside of a skiff and drys one side while the other side is wet. Lots of movement. The bottom might buckle and tear the 5200 from the chine log wood.

    If you want to make a very elegant skiff Why not use " splined seam" cross planking ? Not so much work with a router or table saw and since youre using cedar the planks can be thick enough to spline. Consult a boatbuilding book for the actual scantlings...it been decades since Ive seen a spline seam flat bottom skiff.

    Actually, its been decades since I messed around with cross planked flat bottom skiffs. As for side planking seams...only the chine log is underwater and needs to be watertight...the fore and aft side plank seams are always dry..why use 5200 ? to avoid clench fasteners ? 5200 might work ...how would you clamp the joint ? it might be more trouble than its worth. I would go with nothing in between the side plank seams and a caulked chine log since this is what the construction was for the skiffs I had as a kid. Perhaps 5200 at the stem and stern plank ends.....our crab skiffs used simple Dolphinite type bedding compound....lasted a long time and we really beat up our skiffs....ice, burning sun, sand....


    The skiffs were called Sharptown Barges....about 18ft long and perhaps 4 ft wide. The plans and construction details are still sold...might be worthwhile to spend 20 dollars and go over the plan details for a traditional flat bottom skiff

    http://www.cbmm.org/store/plans.htm
     
  3. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The Monk skiff that appears to be wasn't file planked, but fore and aft and was a very typical traditional skiff build. I too used them as a kid for clams.

    The key to this type of build, is to stay away from the new or modern adhesives and sealants. This is because it's a fastened boat and the parts are intended to move around as needed. You will have the most success with traditional caulk and seam compounds, plus oil based bedding compounds.

    On the other hand, you could convert this skiff to a modern build with epoxy. This would eliminate most, if not all the fasteners, plus you'd have absolutely water tight seams, but it would also mean lots of goo work.

    You sound like you're torn between the romantic notions of your youth and some modern goo's maybe saving the day on maintenance.. Doesn't be fooled, the modern goos will not keep her tight, unless you make adjustments to the way she's assembled and of course use epoxy encapsulation and building techniques.

    For example the dory laps may be held with thickened epoxy, but if you don't encapsulate the planking, it's likely a few years from now it's split, right above the glue line. You could compensate with longer laps, but now you're redesigning the scantlings.

    Decide what you want and approach from that angle. As a rule these traditional build methods don't do well with partial modern build approaches. It's usually all or nothing, so fully embalm in epoxy or use screws, clenches, roves, etc. and deal with the realities of a traditional build.
     
  4. Quartersawn
    Joined: Jan 2011
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    Location: Cape Cod

    Quartersawn Going old School!

    Thanks Guys, The Bottom has 4 wide planks 1/2" Cedar for and aft. Edwin Monk does say the best thing for Dory plank is to be glued, and he wants the transom to be 2 piece spruce butt joined and clamped tight. I was thinking of using the clamping method from the Simmons Skiff to clamp the dory lap together. I am not afraid to clench the planks coated with oil base paint first, But i would like to bright finish the inside and was thinking aesthetically here. as you can see no chine log on this boat or keelson. bottom planks fastened to side plank only. After building the model i noticed how well balanced the design is and you can see right away how light the aft end is with the use of pine skeg, Spruce transom and use of 1/2" planks for rear seat. this Edwin Monk guy was smart! I fear chine logs will make her heavy for the design and converting her to Ply on frame would ruin the whole boat. I can see plenty of well designed Plywood skiffs to build and they are great boats but lack the charm and some have yet to prove they can stand the test of time. I have seen also some wonderful modern planked boats all bright finished and pretty. But i don't want a boat that looks like it should be filled with green and pink M&M's and set in the dining room.I think I will stay traditional with this design as long as I can find some help through the build.
     
  5. michael pierzga
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    michael pierzga Senior Member

    Monk is a pro designer ...Always best to build to design. Sounds similar to Swampscott dory construction. Be aware that vertical grain planking is not the best for the dory lap plank joint...the vertical grain splits easy. Search thru your wood pile for some lapstrake type plankstock with more grain in it. it doesnt split as easy at the lap

    One problem with work boats which use fore and aft bottom planking is they need frames and the bottom of the skiff gets cluttered with dead crabs , fish heads, eels and sand . The cross plankers have no frames and no floor boards...the bottom planks act like frames and the robust keel and chine logs give fore and aft strength. Also when cross plankers swell the boat just gets longer, maybe a bit more rocker....when a fore and after plank bottom swells it forces outward and stresss the chines and plank ends. Use narrow well sealed planks on the bottom to limit the outward swell force on the chine.
     
  6. michael pierzga
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    michael pierzga Senior Member

    Narrow fore and aft bottom planking.....
     

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  7. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Michael, once again, you should stick with what you know. Vertical grain or quarter sawn planking stock is what he wants and is the most desirable.

    A chine log would be a logical addition and it wouldn't add much be way of weight, a few pounds at best. The bearing area, additional longitudinal stiffness and taking the load off the edge of the lowest strake so it doesn't split (a common occurrence with this style of build).

    If the design was converted to plywood over frames, it would be heavier, but if converted to taped seam plywood, it would be lighter (substantially) with 2/3's fewer parts to install as well.

    The jury is long in on plywood skiffs and boats of every size. After a 3/4's of a century of evaluation there's not doubt about it's "staying power".
     
  8. mark775

    mark775 Guest

    I was just going to say some of the things Parr just said (on his first post) and he's the expert on this - I'm not! I have seen 5200 used on similar projects and the wood has been damaged either by the movement of the wood or the removal of the 5200 when it did not perform as hoped.
    Above all else, keep us apprised of your build progress!
     
  9. Quartersawn
    Joined: Jan 2011
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    Location: Cape Cod

    Quartersawn Going old School!

    I am beginning to rethink my design choice with this feedback. Also the Coast Guard just flew One their Big boys low and slow over my house heading north into the Bay. This is a sign! as the whole hose was shaking my thoughts turned to Par advise and firm belief in modern building methods. can i find a Skiff 14-15' long with similar charm and wonderful raking stem designed for ply on frame to show off the wonderful oak I already own. the crab boat Michael showed me is an awesome boat but i would hate to pull it off a mud flat. Getting to old. i am long done with commercial Clamming. Just want to take 3 1/2 men out on the lake to catch some trout and enjoy what I had years ago I guess.
     
  10. michael pierzga
    Joined: Dec 2008
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    michael pierzga Senior Member

    Here...Check out John Gardner... one of the finest boatbuilding and design authors you will ever read...very many simple to build boats from New England. Both Ply and plank. The Dory Skiff in the back of the book is a fine boat.

    http://www.cd3wd.com/cd3wd_40/JF/435/26-674.pdf
     

  11. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    John Gardener was a fine soul and skilled designer, though much more a craftsman. He was alive during the golden age of sail and watched it change as dramatically as it did, in the first quarter of the 20th century. I was fortunate to have met him a few times and he had a most unique sense of humor, which I'll never forget.

    His design work is well known, though is approach was old school. His successful clam skiff is plywood over minimal frames. His pulling craft and renditions of traditional craft mostly are remakes of types he enjoyed or found desirable, more then having original ideas or conceptual thinking. He was the first to give credit where it was due in this regard as well.

    In this vain, the extreme vast majority of Gardener designs will be traditional plank over frames. In fact, I don't know of any modern method builds that he may have drawn up. He did eventually come to like plywood and he had good reason to not trust it, being he lived through it's early years without WBP glues.

    What I'm trying to say is you can have your cake and eat it too, though not with a fully traditional design, if I'm following your desires properly. For example, your intended transom design is a traditional one and a type I repair all the time. They rattle apart under an outboard, then leak and frankly it's unacceptable, considering the options. I've made transoms that look identical to these, but with a plywood core for dimensional stability. They don't leak and don't rattle apart. Even if the hardwood faces open their seams for some reason, the plywood prevents leaks. Personally, I've never seen a plywood core, hardwood sheathed transom open it's seams, but I suppose it could happen if the bond was lost.

    In the end (again) it depends on what you want from the design and what you expect in regard to maintenance. Do you want the traditional build and have to pound caulk, reef out seams and tolerate the occasional leaks, which always seem to get worse each following year or a more modern design, that has tight seams and embalmed wood, but doesn't rot, though requires more initial effort and cost. The finishes (paint and varnish) and hardware are the same on both types of build, just the initial efforts and continued maintenance differ.
     
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