Small Workboat - Advice Required

[Whameller]

I'm looking to build a small workboat for family use and need advice on possible designs. Usage parameters are:

Area Semi protected tidal estuary:

- Some chop/standing waves in open reaches, but no swell
- Tides up to 4kn
- Drying mudflats & some sandy beaches

Capacity 2 Adults, 2 kids (10-14 age range), 1 small dog + picnic/BBQ kit (not camping)

Propulsion

- Primary: Outboard up to 5 HP
- Secondary: Oars
- Tertiary: Punting (only desirable, not essential)

Construction I would prefer ply stich & tape (of which I have some previous experience) for cost & ease of construction reasons.

Weight 2 adult lift. Car-toppable preferable, trailerable acceptable.

Storage Will live outside. Summer often on a mooring or stacked on a pontoon; winter in the garden (yard in non-Britspeak)

Looking for seaworthiness & stability rather than flat out speed.

Have considered Hannu Vartiaala's 15'8" punt, but not sure about seaworthiness of the design.

Suggestions much appreciated !

Many thanks.

[Darren McClelland]

I ordered plans for the sea hoss looks good and sturdy but I also like the Lumberyard skiff in the last small boats magazine, I was thinking of building one for the forty horse motor I have, to haul gear, material and people to islands that I work on for the owners.

Good Luck Darren

[Greg P H]

This one may fit, simple, low power, carries a lot, and stable, though it's a bit heavy for car topping. John Welsford is a member here too.

http://www.jwboatdesigns.co.nz/plans/trover/Trover.jpg
http://www.jwboatdesigns.co.nz/plans/trover/index.htm

http://www.duckworksmagazine.com/06/columns/welsford/index4.htm

[Thorne]

No way you can build a boat to SAFELY carry 4 humans, a dog and kit that can also be cartopped!

And you'll be pressed to find a design that will work well under outboard AND oar, although if you don't have to row very far many designs will be acceptable.

Trover above would be good, and should take the ground and refloat fairly well. It is designed for a 15 hp motor, so will be rather slow with a 5 hp and probably won't plane with a full crew aboard -- but it might plane with just one aboard.

Nichols Lutra Laker might fit the bill if you reduce the size of the crew, and would certainly row and handle the 5ph outboard better.
http://www.duckworksbbs.com/plans/nichols/laker/index.htm

Michalak has some very simple designs that might work, the AF4 being one -
http://www.duckworksbbs.com/plans/jim/af4/index.htm

An easier build would be his Bruceboat -
http://www.duckworksbbs.com/plans/jim/brucesboat/index.htm

More stable but still simple is his Jonsboat -
http://www.duckworksbbs.com/plans/jim/jonsboat/index.htm

Good luck!

[BarnacleGrim]

Yes, there is no way you can build a boat safe and comfortable enough for 4 people and a dog and still be able to cartop it. For a work boat I'd recommend a centre console.

https://www.glen-l.com/designs/special/special-images/dsn-lovb.jpg

If you still want to power it with just a 5 hp engine, the Glen-L Lo Voltage (http://www.glen-l.com/designs/special/lovoltage.html) should work pretty well. Only drawback is that it's designed for an electric inboard. It should be simple enough to make it a petrol inboard, outboard may be more
problematic. Still, for a power boat I'd go with something with more power that planes, especially with those tides.
.

[Spokaloo]

Spend a little time over at www.selway-fisher.com (http://www.selway-fisher.com) , Paul has some great stuff, and he is in the UK. Always a good idea to keep your dollar local.

If you take away your desire to put an outboard on her, the world will open up to a plethora of boats that will suit your needs. A boat that will tolerate an outboard and the load you are talking about isn't too well suited to cartopping, but I suppose its possible.

E

[P.I. Stazzer-Newt]

SWMBO did a lot of biological survey work on the Tamar estuary using an old Tornado - minus the rig - as a working platform.

Perhaps the germ of an idea.

[johngsandusky]

I agree that it would be very difficult to build a boat that carries four and could be cartopped. Look for a used tailer, it adds great flexiblity to your plans. If your looking at low power and rowability (is that a word?), consider going narrower than most planing boats. You'll save weight, and she'll be easier to propel. Consider older skiffs. Sampans aound right, or garvies.
I also warn that it will be tough to overcome a 4 knot current with low power and a load. Don't be discouraged. Study, pick a plan and build it. You'll be glad you did.

[TerryLL]

Seems to me that before you can pick a design to build you must first decide if you want a displacement hull or a planing hull. A boat in the 16' range, with four people aboard, pushed by a 5 HP will have a top speed of about 4 knots. If you're going against a 4 kn current, then you'll be going nowhere. Adding more power won't make it go any faster.

A planing hull will overcome the currents, but for a boat this size, with the load you describe, you'll need something like a 25 HP outboard, minimum. The 5 HP will not plane a boat with that load.

To overcome that 4 kn current with a displacement hull you'll have to go significantly longer than 16' (speed equals 1.3 times the square root of the waterline length.) Going long and narrow will give you an efficient hull that will be easier to row, and the length will permit multiple rowing stations.

In general, a significantly underpowered boat, in strong currents, with the whole family aboard is usually not a good thing.

[BarnacleGrim]

Also, you save yourself a lot of back pain by trailering instead of car topping.

Selway Fisher (http://www.selway-fisher.com/Mcup16.htm) has some really nice motor boats, and so does Glen-L (https://www.boatdesigns.com/departments.asp?dept=10). Also have a look at Spira International (http://www.spirainternational.com/), he has some Carolina dories and some stitch-and-glue boats that may work well.

[Steve Paskey]

Tracy O'Brien's KAYLEIGH might be a possibility. She's an 18' "power sharpie" with a displacement hull, specifically designed for motors from 2 to 7 hp. You could build her without the cuddy if you wish. Downside is that she's beamier than some of the others, and would be hard to row if that's essential.

http://www.tracyobrien.com/moreinfo.asp?id=32

http://www.tracyobrien.com/uploads/kay.jpg

[Steve Paskey]

John Gardner was once asked for a plywood skiff that could be driven with a 5-10 hp motor and "rowed in a pinch." He responded with a 14-1/2 foot "flat-iron" skiff with a beam of about 5'. Complete plans -- including the developed shape for plywood sides -- are in Gardner's "The Dory Book."

And John Welsford did another power workboat that's an easier build than the one listed above. It's called the "Clarence River Dory." The original was designed for fishermen in East Timor. The boat can be built at 16' or 20' long, and the beam is narrow for her length -- only 4'2".

See: http://www.jwboatdesigns.co.nz/plans/clarenceriverdory/index.htm

[James McMullen]

Negotiating 4kn tidal currents is truly possible with a low-powered boat--I do it all the time. All it takes is seamanship. . . . . . . .okay, actually just patience and planning. You see, first the tide goes this way, and then, later, it goes thataway. And often there are eddies you can take advantage of so that you can keep going this way even when the main current isn't.

I guess the biggest trick would be to find three other people plus a dog who are willing to be patient with you.

[JimD]

Welsford's stitch and glue Cobble is about 17'x 5'4" http://www.jwboatdesigns.co.nz/plans/yorkshire/index.htm

[Bob Smalser]

http://pic20.picturetrail.com/VOL12/1104763/9745605/291368019.jpg

The most stable work boat I've ever experienced is John Gardner's 12' Fred Dion punt described in Building Small Craft Volume I.

http://pic20.picturetrail.com/VOL12/1104763/9745605/282785146.jpg

I use it for sunken log recovery and as the family's all-around beater boat. While it's designed to row and scull, I've powered it a couple times using an old Seagull when I needed to. It's surprisingly seaworthy and I've carried as many as 6 loggers and their gear in it while also towing logs. Dion designed it for heavy-duty marine railway maintenance and Gardner provides anecdotes on its successful use in during hurricanes.

I built it because it skids across mud flat shallows exceptionally well and gets on and off stumps and obstacles easily when loaded. More buoyant in the bow than stern, to get off an obstacle all you have to do is move to the rear oarlocks and row off. No swimming required.

http://pic20.picturetrail.com/VOL12/1104763/9745605/138774735.jpg
http://pic20.picturetrail.com/VOL12/1104763/9745605/138774744.jpg

Mine is 7/8" cedar on Doug Fir built to the original Dion scantlings and lines. No lofting required. It can go together in a week if you are an experienced builder. A trailer is required, of course. After almost a decade of use the only change I'll make for the next one is to double plank it, which isn't a big task in flat-bottomed carvel. The rear single planks at the skeg ride out of the water in summer and dry out enough to weep when you first step in the boat.

http://pic20.picturetrail.com/VOL12/1104763/9745605/138775352.jpg
http://pic20.picturetrail.com/VOL12/1104763/9745605/282787721.jpg

For your purposes in the UK I'd probably use native oak and larch and reduce the scantlings by 10-25% to pare unnecessary weight. 5/8" larch instead of 7/8" cedar sides, 3/4" oak instead of a 7/8" DF transom, 6/4 oak instead of 8/4 DF chines and two layers of 3/8" larch on the bottom. It'll be a lot easier to make those bends in oak than fir, too.

[BarnacleGrim]

What kind of work will you be using the work boat for?

[Jon Agne]

Heed the trailer advise! I have an 14' Wm. Atkin skiff and getting her a small trailer for transport was one of my better decisions. I also use the trailer to haul other tenders for myself and sailing friends, and I have even used it to haul timber beams.

I was also going to recommend looking at Bolger's Fisherman Skiff. He has a couple different lengths, but I must say that I am smitten with Bob Smalser's punt by Garden.

[Whameller]

Thanks for all the excellent advice - considerable food for thought and some designs that I had not already come across.

To lay to rest a couple of developing red herrings:
- Looks like car-toppable is not compatible with the rest, so I'm quite happy to trail it when necessary.

- 4 kn tides only occur in certain parts ot this 22-mile estuary and only at certain states of tide. I entirely concur with the remark on seamanship above. I don't aim to be pushing against 4kn if I can help it, but I do need to be able to do so in extremis. For those who know it - the Milford Haven/Cleddau River waterway in Pembrokeshire.

- My 5hp outboard pushes my 17' Lune Whammel (gaff sloop, displacement - and how - hull) along just fine at sea or inshore. The motor has to do for both vessels. Not interested in going for more power. In any case, upper half of the estuary has a 6kn limit as its a nature reserve.
My main concern with some of the punt designs is seaworthiness in wind over tide estuarial chop conditions, which can be quite common in the more open reaches. The Welsford designs are attractive for this reason.

If I had to prioritise the design parameters, I would go for seaworthiness under power, capacity, rowability; ease of build remains a factor of interest.

Thanks again.

[Thermo]

I thought of Bolger's 18' Clamskiff as outlined in the newer Payson Book:

http://books.google.com/books?id=qHuCGU8f7T4C&pg=PA134&lpg=PA134&dq=18'+clamskiff&source=web&ots=vlBBdNV6IB&sig=R5U0G9SvVQSW_HNnDbGQzGAUyog&hl=en&sa=X&oi=book_result&resnum=1&ct=result (http://books.google.com/books?id=qHuCGU8f7T4C&pg=PA134&lpg=PA134&dq=18%27+clamskiff&source=web&ots=vlBBdNV6IB&sig=R5U0G9SvVQSW_HNnDbGQzGAUyog&hl=en&sa=X&oi=book_result&resnum=1&ct=result)

Probably won;t get much easier to build than that.

[Fritz Koschmann]

Ken Swan has some very attractive, to my eye, simple skiffs. He has a variety of designs including rowing skiffs that can accommodate a small outboard, sailboats and outboard displacement and planing skiffs. They are all simple flat bottom boats.

http://www.swanboatdesign.com/gallery.html

http://www.swanboatdesign.com/images/gallery/nezperce13.jpg

http://www.swanboatdesign.com/images/gallery/chica1.jpg