Double Plank Fastners

I'm thinking of building a big skiff (25-28') like the big Atkin flat bottomed boats. Would like to end w varnished Red Cedar topsides but it would probably wind up a trailerboat so I should probably go plywood but I want the Cedar. If I double plank w 3/8 or1/2" planks .. what would some of you wood vets recomend for fastners? Screws was my first thought but not much wood to anchor in. Bad idea I figure. Pop rivets would be great but obviously the boat would sink. Double bent clinch nails (copper) is the best I can think of but the rivets used in lapstrake const are probably the best but am not familiar w them. I could do the first plank in Yellow Cedar to increase the holding of the screws. If I keep the planks 2 1/2 to 3'' wide and bedded w Dolfinite would the boat be as water tight as plywood? I guess that's enough questions for one post.

Easy Rider

 

If really interested in a faux cedar planked topsides, you should consider a veneer which can be easily glued to the plywood topsides. It's lighter, cheaper, easier to apply and you don't affect the scantlings with veneers.

If you're thinking about boats like Wader, Marigold and Esther all of which are trailerable, you should wait until you get the plans or select a different design. All of these are carvel planked boats and knowing the father/son work as I do, you can rest assured the planking will be fairly heavy (thick) and not surprisingly cedar will be called for. In other words, these aren't developed panel designs and the plywood will have to diagonally applied or slit in areas (like a flared bow for example) to accommodate the compound curves. Is there a reason for using these designs? They're quite dated, don't employ modern materials, practices or techniques and you get what you pay for, meaning both designers are dead, so no help there and the plans can be somewhat lacking if you're a novice builder. Again, is there a reason(s) for one of these Atkins designs?

 

Atkins?

Yes, I really like his designs and like William Hand he designs good boats for speeds between planing and disp. It should be easy enough to modify Atkins designs slightly as well. Dated? .. fine if it's the boat I want. I want a big skiff thats best at 10 to 14 knots. Do you know any designs better that Atkin? As to materials I live in SE Alaska and we have a number of sawmills that cut red and yellow cedar regularly. Would like to show others they can build a good capable boat from local wood that's much bigger and performs well w much lower power than the usual aluminum skiff. What I have in mind is a planked boat like a batten seam boat where the battens are the same size as the base plank. I would think w a nice soft bedding compound it should be water tight. I'll probably need to use yellow cedar for frames ect as other local wood (spruce & hemlock) are less desirable. PAR, have you got any ideas for plank to plank fasteners?

Easy Rider

 

Copper nails and roves (rivets) are the answer. And why not just lapstrake plank the boat?

Clench nails are horrible.....impossible to repair without destroying something and can cause splitting of the plank edges. Riveting will require a helper and lots of hammering in this size boat...but it's forever and you only need to plank the boat once.

 

Both clenching and roving can be done solo on a new build. Using Dolfinite or other traditional oil based bedding compounds wouldn't be a good idea, as it has no real elasticity and must remain under pressure to be effective. Modern adhesive/sealants are far superior in this regard, with elasticity rates of several hundred times their original position.

Clenches are well tried and valued around the world, though some may have issue with it, others have developed whole company reputations on the method, such as White Canoe and Lyman. They're not difficult to remove once you learn how and fairly easy to replace, again once you learn how. Clenches that split plank edges have been installed incorrectly, in fact, a properly installed clench will help prevent the edge from developing a split. Given a choice I'll take a rove or better yet a through bolt, but clenches are lighter and less obtrusive inside the boat. For the size boat you're looking to build this will be in neighborhood of 4,000 maybe 5,000 plank fastener count

Some of Billy's older designs are batten seam, but most will be carvel. Maybe you're skilled enough for this type of scantling conversion, but your questions suggest you are not. These boats are heavy by today's standards (by a large margin). Yes, there are several designers and many designs that are better then the 50 to 90 year old efforts of the Atkins family. It's not that I don't enjoy their work, I do and own a 40' John Atkins box keel yacht (John's favorite). I do suspect you'll will not find these modern design, plan packages priced at $40 to $90 though.

 

Thank you PAR and Tad for your excellent input. For some time the boat I wanted to build was Handy Billy (the 26') even before it existed. I want a boat that shines at S/LR of 1.5 to 2.5. Very very few do. Atkin Boat Plans present a near exact boat to Handy Billy called Tang. While looking at Tang I drifted off to Wader. It snowed yesterday and I don't think much about boatbuilding in the snow.
Easy Rider

 

Waterproof Pop rivets are available but not easy to find. There's also a 2-piece version that is flush on both sides but it might need 2 people to insert. The specials can be quite expensive though. Get the power gun to save your hands!

 

its terrific that you have such fine timber supplies, here we struggle to get good cheap wood, i dont know what youd use for such thin planking, we planked a commuter with screws from inside, but that was a lot thicker,

 

Cedar

Hi Peter Rad,
We do as long as it is Y Cedar, Red Cedar, Sitka Spruce or Hemlock. I have a pile of excellent (1/3 boat quality)Red Cedar 5/8th X 6 X mostly 10' availible to me. $1000. It's about 3.5' wide and 3.5 - 4' high. Still stewing about getting it. I need some for my carport so I'll have another look then.

Easy Rider