View Full Version : Rough water runabouts
Jackie3
12-23-2006, 08:20 PM
I am trying to find a high powered runabout in the 19 to 22 foot range that has good rough water capability. I am a current Donzi 18 owner and a long time dedicated fan of the name. Unfortunately, I am starting to get a little too wet and bounced around as I drive more and more aggressively in rougher water. I want to move to a drier boat but want to stick with flat deck runabout design. I'd love to think the answer was a Hornet or 22 Classic but these hulls haven't been changed in 35+ years and do not react well to the kind of power I'd like to use (496 Mag HO or higher). Donzi fans reading this are cursing me right now but no one will deny it: the soft keel at the transom rolls up nasty, slides hard on deceleration and acts generally ill-mannered under big power and long props. I'm certainly not saying Powerboat is the last word authority by any stretch but check out http://www.powerboatmagazine.com/2002tests/jan1.php. I hated reading this but had no trouble believing most of the negatives.
One more thing - I'm not wild about driving anything with a stepped hull so my options are extremely limited. Any suggestions???? Thanks!
Ritara
12-28-2006, 01:26 PM
I might have a suggestion for you about a runabout for rouch waters, but are you thinking of a classic looking runabout (mahogany and stuff) or just any plastic toy?
Jackie3
01-02-2007, 03:07 PM
Ritara,
I've spent most of my years in "plastic toys". I'm almost dumb enough to enter a wood vs. FRP debate, but not quite (and certainly not on boatdesign as I'd swiftly be tarred and feathered). I've read many posts on this site and I know that its contributors typically have a firmer grip on design concepts, even for powerboats, than what you'll find on many go-fast forums. For what it's worth I have 20+ years in aerospace composites and am sold on the hi-tech stuff.
In my opinion many of the classic wooden rigs (Gar Wood, Chris Craft, etc.) aesthetically mastered the perfect hull and deck styles. But functionally I would like to find an advanced FRP hull in a boat under 23' outfitted for high powered IO application.
Ritara
01-02-2007, 03:28 PM
This boat I have in mind is just designed like a real "runabout", but have the real V-bottom and can be made in any material really, allthough it deserves a wood-look. Go composite and have fun!
Hmmm...how can i show it to you?
Jackie3
01-02-2007, 04:34 PM
Are these plans or is the boat in current production? Website locations?
Loveofsea
01-06-2007, 07:39 PM
Hello jackie. Back in 91' i designed and built a 19ft wooden flatbottom dory style skiff. I have since logged over 55,000nm of open sea sea travel. I run the seas off Southern California year around and i have experienced all kinds of weather and i have never seen a skiff that i would rather be in when the going gets rough. Let me know if you are interested in knowing more about the Good Skiff...
My motto: There is nothing like the feeling of utter security on a tumultuous sea~
Jango
01-07-2007, 09:07 AM
I fully understand the many advantages to the "Plastic Toys" , I've owned a few of them, but for me, there's nothing to compare with my 20' Chris Craft clone, especially when I open her up to over 80 mph.
Jackie3
01-07-2007, 01:53 PM
Loveofsea,
The skiff sounds great! I don't know much about flat bottom designs and would probably beat it (and myself) up pretty bad learning to operate it. I have heard they handle very well in rough water if you know how to operate them. I've seen many 20-30 foot aluminum fishing boats in professional use in The Great Lakes which are relatively flat. As for your boat, I knew a guy in Cape Cod looking for just such a boat last year but he has since made a purchase. I fear I will always go with the deep V style myself.
Jango,
80's movin' in w:eek: :eek:d!! Got any pics of this boat? What's 20' of wooden boat weigh before power and rigging? Inboard with a nuclear reactor? I'd like to leard more about what the design on these bottoms is like. Any web sources?
Jango
01-07-2007, 04:46 PM
Jackie3, I agree the deep Vee design is probably better in rough water, but at the expense of performance. My mahogany boat is a twin cockpit design & has only a 4 deg deadrise at the transom, increasing to a "concave" deep Vee towards the bow. The concave Vee not usually seen on Plastic hulls greatly tends to smoothen out the ride in rough water.
Hull is of cold molded construction - 3 layers of thin wood, encapsulated in Epoxy. Hull is very strong, yet lite weight. Powered by a Sm Blk Ford, stroked to 327 c i, producing over 400 HP at the Prop - total weight w. half tank of fuel minus driver is 1985 lbs.
I'll post a picture once I figure out how to do it.
Jango
Take a look at the "Alpha Z" in the Custom wooden Boats section :
http://www.vandamwoodcraft.com
(Not my boat but I wish it was)
Jackie3
01-07-2007, 05:10 PM
Now I get where the speed comes from- 1985lbs at 20 feet is exceptionally light. I think my '78 Donzi 18 comes in around 2300 dry. I assume the concave area you refer to up front would be seen if a straight edge were placed from the keel to the rub rail. This is actually common to a lessor degree in some early glass boats but only noticeable in the most upper section toward the deck (although this feature was much more prominent in some Donzi's like the Hornet model). Makes the boat alot drier in rough water from what I've experienced.
Did you work from plans or derive the basic hull shape by reverse engineering?
Jango
01-07-2007, 08:23 PM
My boat was built from plans - GlenL "Monoco". Design was changed however - hull was made deeper and slightly longer. (bottom as per plans)
Max amount of concave in bottom is about 2", probably 5 ft from the bow.
Jango
Eric Sponberg
01-08-2007, 04:22 PM
Jackie3
Have a look at my Cherubini Classic 20.
http://www.sponbergyachtdesign.com/CC20.htm
It is a very smooth riding boat and does very nicely in waves. This has fiberglass construction with a real wood overlay on a fiberglass deck. Power is available as a gasoline jet (Mercury) or with gas or diesel I/O drives. Another modification we'd like to do is a conventional gas inboard. You can contact Cherubini Yachts at
http://www.cherubiniyachts.com/
Eric
Jackie3
01-08-2007, 09:05 PM
Jango,
That boat is beautiful! The two tones in the deck giving the racing stripe effect are a perfect touch. The deck shape with the barrel back and almost everything flushed out is exactly what I would choose. I'm not sure if it's concerns about X dimension or what but most glass boats (IO's anyway) tend to pop up some portion of the deck taking the clean lines away. I don't get it.
Eric,
Hope to see the Classic 20 in Miami this year! Looks great! Not to sound pure gear-head but you offer 5.0 Merc IO - if you're doing 50 with less power what do tests reveal about this option? I have a bunch of questions about just how this boat handles in heavy chop, how dry it is etc, plus some questions about ProSurf, but I'll wait until next month if you or a rep from the company will be at the show next month.
General observation- there aren't any alters to Don Aronow at my house but he was one of the only guys to bring some of the look and feel of these classic designs to high-powered fiberglass in the 20' range. Evidently, not one creative thought has ever been given to it since. However, if you want a 33 footer with three steps and two big blocks the world is your oyster.
Jango
01-09-2007, 08:46 AM
Jackie3,
I suspect the glass boat designers want that "long slim look" which often doesn't provide enough space for engines etc. necessatating "pop ups" on the Deck.
To gain the required vert. space, I raised the deck 3" from transom to forward cockpit and then tapered to bow.
Thanks for the kind words,
Jango
Eric Sponberg
01-09-2007, 09:50 AM
Jackie3,
Thanks. I will not be at Miami, but I think the boat will. The best speed we had, as I recall, with the 220 hp Mercruiser was 62 mph. With the 5.0 liter 260 hp engine, properly tuned and set up, we should hit about 66-67 mph.
Regarding pop-ups, the CC20 was originally designed around the Mercury jet pump at 170-240 hp. Now all they offer is a 250 hp set up which is considerably taller than the original. As a result, the hatch had to be modified with a cowl which really destroys the lines of the boat. There seems to be more popular appeal to the I/O drive, and I think a conventional inboard (4.3 liter with Walter V-drive) would go over well. The tooling is set, so we can't change that without a huge investment in new deck tooling to accommodate a straight inboard drive.
Eric
Loveofsea
01-09-2007, 08:01 PM
Beautiful looking boat!
But it doesn't really look like a rough water runabout. How far ofshore has that boat been? Do you run the seas in it?
just curious~
Jango
01-09-2007, 10:26 PM
My Runabout has never seen the sea. To date, has only run on the Ohio. Has encountered some 3' - 4' swells from tug boats and waves from paddle wheelers and other boats. Fresh water Boat only.
baddawg29
06-27-2010, 11:11 PM
Hey Jackie Im not sure if you are still looking for a fast boat but in my oppinion the best one I have found so far is now called a riviera but originally it was called a roughwater its found in the miami area and there was only about seven or eight built they are 17' 8" and are very similar to a donzi but the bottom is slightly different and they are a very smooth and stable ride at high rates of speed mine does 86 mph by way of handheld gps and it was very difficult to find this boat im 28 years old and i have been on the water my entire life and i have personally only seen two of these boats and now that I own one ill never own any other but this is an oppinion and everyone is entitled to thier own but if you can ever find one of these boats im sure you will be pleased.
View Full Version : Rough water runabouts