Dave Gerr's Offshore Skiff

[PhilM]

I find the concept of a flat bottomed offshore skiff (strong dory influence), facinating, and I really like its look. I am well aquainted with the different hull types, and the flat bottom for offshore use is very interesting. The moderately low power requirement is also a big plus. I would think that when the going gets rough, this design would have to be quite seaworthy at displacement, or perhaps semi-displacement speeds. I would also think that the ultimate stability would be very good. I realize that with its narrow dory bottom, its small for a 28 footer. Please comment.

[fcfc]

See previous post from Tom Lathrop http://www.boatdesign.net/forums/powerboats/pocket-cruisers-11670-19.html#post114700

[PhilM]

Thanks for the link. The information is very informative. I continue to be curious about its seaworthyness when you must slow down below planing speeds in conditions that would result in heavy pounding of the hull. Tom's comment that its very tender at the dock comes to mind. I wonder about how drastic a roll she would get into in various sea states, at for instance, 6 to 8 knots. I like the double chine.

[Homefront]

Phil,

I have those issues of Offshore Magazine in which Dave's skiff was published, which I bought when they were on the news stands. It's a great design, easily built, sturdy and seaworthy.
My own thoughts on the design:

The boat will pound some in a chop; unavoidable with a flat bottom, but a trade-off for some other good traits.

The full bow and upswept bottom will not root around in a following sea.

For my uses (inshore and offshore fishing) I would build a narrow, walk-around pilothouse with a foam core roof, and a canvas/aluminum tubing enclosure to keep the above deck mass to a minimum. I might build some kind of storage up front with a large dodger, for those private moments. I think this would minimize the boats tendency to roll.

[frank smith]

Years ago Texas dory was selling plans for a Carolina dory about 20' long .
They said it could be scaled up to a larger size with out problem. One guy went up to 26' , and it worked out fine . I think Gerrs boat is basically a scaled up
Carolina dory with a little lift to the bow , I think you will find the flair to be the same in both . They are very efficient shapes , as Gerrpoints out . allso cheap to build .

[PhilM]

I really appreciate the replies. Homefront- Would you be able to tell me the issues of Offshore Magazine where those articles were published? I strongly agree with your assessment of keeping the center of gravity low. I wonder how many were built. I would like to see one some day. thanks.

[gonzo]

Check out this link
http://www.stonek.com/banco/index.php?textfield=pesqueros
These boats fish in some of the roughest areas, with more than ten hurrican force winds a year and frequent gales. I grew up there and fished gill nets. The flat bottom boats handle well.

[PhilM]

Thanks Gonzo- I really enjoyed the photos. Its obvious to see they take advantage of the flat bottom in beaching. You actually woke up an old memory of mine in mentioning your experience. As a young man I spent several months living on a 40' traditional sanpan, fishing for Ahi, longlining, in Hawaii. Although I never saw it out of the water, it was in all probability flat bottomed. I don't remember having any doubt of its seaworthyness. Regarding Gerr's Offshore Skiff, I've been wondering if in making a dory a planing boat, rather than a displacement hull shape, are the seaworthy characteristics lost. I am understanding from this thread that many of the positive characteristics are maintained. Thanks.

[frank smith]

you might want to check out the Oregon dories , they are much the same in
basic function . I think that by narrowing the bottom towards the stern Gerr has done the best that can be done to distribute the displacement of the boat .
It is narrow and this is good for getting the draft down , and increasing stability. I would not think twice about building one if that was what I wanted .

http://www.northwestmagazines.com/oregon_coast_pacific_city_dory_fleet.php

[PhilM]

Yes Frank, the Oregon dories have a great reputation. In my humble opinion, the balance of the design characteristics of a seaworthy dory, and a planing skiff is the bottom line of a good seaworthy, yet moderately fast and efficient design. Any design with parallel sections aft will plane well, but could be an issue in a following sea. On the other hand, too much taper will defeat efficient planing characteristics. I've been thinking that Gerr has designed an excellent compromise . It just looks right to me. Thanks.

[gonzo]

A planing flat bottom boat with a lot of flare handles well at lower speeds. That makes it quite versatile. You need to slow down earlier than a deep V, but is will be more seaworthy just moving along.

[PhilM]

OK Gonzo- got it. It is seaworthy at slower speeds. thanks.

[TollyWally]

Nice pics Gonzo,
So you grew up gillnetting in Uraquay? Would you mind filling in some of the details? Were those boats in the pictures gillnetters? I didn't see any nets or drums. I saw some smaller fish in a tote and some sharks being carried up from the surf. I did admire the armstrong winch on the beach!

[gonzo]

Some of them longline. The gillnets we used were set and picked up by hand. One man on the bow did most of the pulling, one in the middle taking out the fish from the net and a third one coiling the net in a basket. They still do it like that. They also use seines set from the beach. There are poles set by the shore where one end of the net is fastened to. The other end gets taken out by a boat that makes a large turn and then gets beached. Then either you hitch a horse or have enough people to pull the net in.

[TollyWally]

"Then either you hitch a horse "
They used to do that on the Columbia way back when.


I enjoyed the pictures very much, thanks for posting them.

[gonzo]

You're welcome, they bring good memories

[Homefront]

Phil,

The issues that contained the article and offsets were September and October of 1990.
They don't contain complete plans, but enough details to work it out. If you've built a boat before and have any confidence, I believe it could be done.
David Gerr might differ on that point.

[frank smith]

Dave is on this forum , shouldn't be to hard to ask him.
The plans couldn't cost that much.