New memeber, lapstrake, gokstad faering and pvc foam

Evening all,

Just so we're clear I'm new to both forums and lapstrake so I apologise if these are daft questions. But wanted to ask members of the boat building communitie that have a bit more experience.

I've made two stitch and glue kayaks and want to expand my knowledge and move onto lapstrake/clinker building. I've done a few months of research and read a few books and it all seems reasonable.

Id like to make a Viking style gokstad faering. Because the design sounds perfect, light but (calm) sea/loch/lake/river/fen and broad worthy, one or two rowers and possible sail mounts. But scaled down to canoe size so I can get it on the old KA.

So here come the questions..
I've looked and looked but still can't find complete enough plans, anyone know were I can get hold them?

Second is a material I want to try... PVC foam board... now hear me out, its light, flexbable and bouyant and can be cemented, bonded and is easy to cut. How about replacing every other strake with PVC foam, reinforced with fibreglass/ carbon fibre sheets and epoxy? Bring the weight down and possibly help with bouyancy.

Any thoughts or help would be great help.

Thanks
Ben

 

That sounds like a recipe for disaster. It will be expensive and heavier. They still make them in Norway in the traditional way. The methods have been refined through centuries and you would do well to follow them. Mostly, people apprentice and learn how to build them. I don't know if there are any plans with every construction detail available.

 

Welcome to the forum. Gonzo may be correct, in that re-engineering the planking and scantlings may not be as wise an idea as at first thought. Lapstrake, either traditional or modern, glued, clenched or even tied is one of the lightest building methods available, unless you move into molded veneers or high tech cored and sandwich structures. I wouldn't advise a traditional lap build, for a drysailed boat, but a glued lap is a very good alternative. There are plenty of lap canoe designs available and these could have aesthetic changes made, to make them look more like what you'd prefer, except the engineering is already done, so it'll float right side up on launch day.



These puppies are fairly "burdensome" things, so making one light enough to be car top ready, will be a challenge.

 

Thanks both for your replys and advice, I'll keep the material ideas out of the way for now and I'll start looking at canoe designs and that pictures looks ideal.

PAR your profile mentions your a desighner/builder and as someone who'd really like to start really understanding boatbuilding and how it work and the science behind it, can you suggest any books/DVDS/people to learn from without doing an apprenticeship?

Thanks

 

Try these guys for information:
Grindverk barn - Bjørkedal wooden boat museum, Norway - 123vid https://www.123vid.net/video/grindverk-barn-bjørkedal-wooden-boat-museum-norway-ddfeff7129addbf57c3803.html

 

Studying both the science and methodology behind boat design and building, takes a life time and you still don't get it all, just what you're' most experienced at or interested in. There are many books on building, though I'd suggest you focus on the method(s) you'd like to work with, to limit the scope a bit. Hydrodynamics, design, engineering, etc. are a fair bit more time consuming, but start with the basic "primers" like Ted Brewer's book or Dave Gerr's efforts. The "Elements of Boat Strength" will give you a fair footing, but I'd recommend "The Nature of Boats" as your first read, both by Dave Gerr.

 

Thanks again,

Books on order and they've got great reviews and look like a good place to start.
As for methods Lapstrake/clinker has defiantly caught my eye but I can only really build small craft because I'm limited to a garage. I think a small glued lap canoe will be the place to start. Do you think building a model first gives an accurate representation on the skills needed? Like joining stems to the keel and cutting rabbet lines at the right angle?

 

I find that models help visualize the shapes and methods.

 

It depends on the scale of the model, but yes if it's big enough, so it's not so much model building, but exploring the building method and not an exercise in whittling.

If looking for the lightest go full up "glued seam lapstrake", as it'll have the least number of frames, floors and other elements, which just makes it lighter. This method also doesn't rely on moisture gain to keep it sealed up tight, so perfict for a trailer or car top craft.

 

Ian Oughtred is a very experienced designer of glued plywood lapstrake boats, several of which are based on traditional Scandinavian designs. Look at his interpretations of Norwegian Hardanger Faerings, and his Double Ended Beach Boats. http://www.oughtredboats.com/

 

There are a couple of points you should be aware of.

1/ The original boat is not a lightweight. It's designed for a fairly substantial displacement, and IIRC the boat itself weighs around a quarter of a ton. You would want to choose any re-scaling carefully to get a usable result.

2/ It is designed for rowing, not for paddling, so if you think scaling it down to canoe size would make a good canoe this may not be the case. Basically, it will be too wide at the sheer if the underwater bits are right.

3/ If you want to scale it down but keep it for rowing, then you are limited by the need to keep an adequate width for oars at the sheer. At a minimum this would be somewhere in the 1.1 - 1.2 metre range, IMO. The original is only around 1.4 metres wide, IIRC.

Viking ship museum at Bygdøy has plans, at quite a reasonable price last time I checked. I used to have a copy years ago, but don't know what happened to them.

The Viking Ship Museum - Museum of Cultural History

There is no need to worry about language, as the staff are fluent in English. Do be aware that the plans were drawn for the use of experienced builders, and are probably not something a complete beginner could build from unless they were prepared to spend some time reading up on things. Also be aware that the plans were drawn for traditional construction, and would need to be adapted for more modern construction methods. Apart from anything else, you won't be hewing the entire fore and aft sections from a block of oak.

Which brings up another point. The Gokstad faering is incredibly elegant if you get it right, but it is also easy to get it wrong. I've seen "replicas" that looked like a dog's breakfast. I would seriously advise making a largish model first if you are not an experienced builder.

As for construction: glued lap plywood is the only sane choice if you want it light and want to cartop it.