Boat Builder Central - Builder Forums

Alright designer-guys, Im here to learn.

How is it that the Frost Torpedo, as redesigned by some shops in Maine and built at Rumery's, can do 32 mph? It isnt a planing hull by any stretch, it has waaay too much slope in the aft sections (no monohedron), its soft chined, and has a VERY sharp entry. They estimated 15-18 kts, but it ran wildly past expectations.

38' LOA, 9' beam, round bilged, and driven with 315 hp. One of the builders is quoted at being able to get 6gph at 30mph. THATS 5 MPG! Pretty far stretch from the 1-3 most boats get.

Id love to know how it works, because I think itd be an interesting boat to develop in this technique, as it could be an extremely efficient commuter, or with a sailboat-esque trunk, could have vast accomodations.

http://www.rumerys.com/T38%201%20folder/T38.6

http://www.rumerys.com/Torpedo38/T38.1%20header.500

(couldn't get the images to post to the forum without loading elsewhere)

I know it has similar proportions to the FL26, but It looks to be a very different boat as far as running characteristics, even exceeding a certain commuter by another designer.

E

A different looking boat to say the least. I'm no expert by any means. Far from it. But I find the thing fascinating. It is squat and has more hull above the water than below. From the wheel back it is all above waterline.
duke

nm

Looks like one of my favorite Eastern Shore workboats — a Chesapeake Bay Hooper Island draketail.



“The "Hooper's Island Draketail" was named after the small island located in the lower half of the Chesapeake Bay on Maryland's Eastern shore. In the early 1900's, when the internal combustion engine first appeared, watermen were trading the sailing rigs for the engines and the local boat builders were looking for new ways to build better and more efficient workboats. One such builder noticed the torpedo boat destroyers pass by his home, and he thought that the hull design would be good for a workboat. He copied the hull design and built a boat with a V-bottom. The boat was fast, good looking and because of the narrow beam and sleek lines, it was relatively inexpensive to build.

The design caught on and the boats sprang up everywhere. The boat acquired the name "draketail" because the stern resembled the back of a duck's tail. A few years later, a new box stern type became popular, and the draketail became old fashioned. Eventually, the full name was shortened and now most people only know them by the name "ducktail". Today, not many of these beautiful boats exist. But through the passage of time, the boat has become a classic.â€

D2, good call on the Leonard W (which happens to still be in the back shed at Rumery's). From what I heard, the Lowell boys saw the hull during its construction and said it was pretty bastardized from an original Frost. Apparently they built in some of the hog it had developed over the years and didn't get some of the lines right. Sounded like the sheer was off and the buttock lines were different than initially intended.

Frost's boats were fast, but were they as fast as the Torpedo ended up? I wonder if the draketail really made a big difference.

Pete, Ive always liked the downeast workboat look, almost (but not quite!) as well as the PNW salmon trollers. Frost was supposedly the godfather of the modern lobsterboat, and thats pretty obvious in the photo you posted. Thanks for the short history.

It just seems like that boat gets through the water so stinkin efficiently, I want to see how it applies to a smaller boat. That 38 would be a blast as well, or something similar (34' is such a nice size for near-shore waters).

E

I love the Hooper Island Draketail. Wish somebody had plans or somebody would do one, say in a 25'-30' range.

Right now the only plans I know of for a draketail are from Kaufman Design. http://www.kaufmandesign.com/stockpln.html

The 20' Hooper Island Lauch


David

It is easy to design such a boat and get the same performance (minus the hype).
To keep it brief, last month, Joel and I participated in a seminar given by Nigel Irens. He explained the theory, nothing new but well applied by him to his Range Boat. Read about it here:
http://www.hiswasymposium.com/pdf/2004/ ... 0Irens.pdf

The most interesting part is not in that paper but was discussed with him after wards: why do those boats and plans not sell?
(Range boats sold 2 or 3 units in 4 years!!!!)
Because they have limits that people do not accept (or understand), because marinas charge docking fee by length and because of misconceptions.

People do not accept that those boats must be light and narrow.
See all the questions about the Nina (LB22): can I raise the freeboard, add a cabin, widen the boat?
They often reason that if they have a 26' boat, it must have the same double cabin, galley and shower than in the Bayliner they saw at the dealer.
They buy the Bayliner but since a Sunday afternoon trip cost $ 200.00 in fuel, they stay at the dock with it. In the mean time the Range Boat owner is cruising and cruising and cruising.
They don't cruise but at least they have headroom in the shower.


VSLH are a great concept but a commercial fiasco.
I already designed the LB22, the FL26 is coming soon and if it works, you will see more.
There is no magic in the design. I have many lines plans and specs of those hulls including the Hooper Island Launch and probably the Torpedo. The design is not the problem, the problem is with the choices made by the builder/owner.

There is hope on the horizon: crude oil is going up and we may not be able to afford gas guzzlers anymore.

Vman777 wrote:I love the Hooper Island Draketail. Wish somebody had plans or somebody would do one, say in a 25'-30' range.

The Chesapeake Bay Maritime Museum store has plans for “Martha,â€

See, we need a section of the forum where the designers can post some of those essays and documents on design. Not only does it help make sense of what our boats are doing (and is incredibly interesting to someone like myself who wants to learn as much as he can), but can also better explain why you design something a certain way and may reduce the number of people who want incongruent changes. When a question pops up, just shoot them a link like that.

How about this?

28-32'
deep, narrow forefoot
speeds similar to those of the other drakes, cruise at 12-20, top around 30ish
sleeping for 2+2 ( +2 may be out in an open wheelhouse with canvas)
Soft boot-type enclosure that pops out of the cabin top for a full height shower ( remember, 6'3)
head
Small stove to make some food on

Too much? Not looking for a trawler, but getting the most out of her limited load-carrying ability.

P.S.; SWMBO just gave this the go-ahead, she likes it.

E

The FL26 is a minimal version of what you just described.
It could have a vee hull and be longer but the philosophy of the boat is identical.

True, minus the ability to be driven past hull speed, the drake tail, and additional length to allow for slightly less spartan accomodations.

She likes the FL26 as well, but shes needing a shower on board. Id like an open backed low shelter for the pilot (rain, relatively common over here) which requires more length to compensate. I really like that boat's concept, but I know that more length is required to make her happy in a boat we can take out on the salt water.

Its a very interesting hull, esp seeing the wake left behind the ones with a true drake and no transom.

E

The FL26 will go well above hull speed but to get a shower with headroom, we have to look at minimum 30' with vee hull, 35 flat bottom.

I really like the Osprey and the calliope. Lots of room aft and comfortable digs for short cruises. Nice lines and dollar signs A couple could fish for days and days. I'll never own one but its nice to dream. Maybe someone will end up doing a S&G version and I could catch a ride.

Duke

Spokaloo wrote:See, we need a section of the forum where the designers can post some of those essays and documents on design.

It is called "amateurboatbuilding". OK the forum is unstable because the software on the back end is out of date. That is something I will be working on over Christmas.

We have designer neutrality (Jacques and Tim Reiters are on it for example) and active posters with ideas from other continents (this means you Toni_V). If I can keep it up and running (new software) I will animate it.

Tony

Spokaloo wrote:T
She likes the FL26 as well, but shes needing a shower on board. Id like an open backed low shelter for the pilot (rain, relatively common over here) which requires more length to compensate. I really like that boat's concept, but I know that more length is required to make her happy in a boat we can take out on the salt water.

1. Up until recent times people showered:
- outside on the swim platform
- in the head seated (my solution)
(read the article in salon.com on the hygene problem in your culture, you guys shower too often...)

2. Sun + rain = for me a light weight roof with opening "sun roof" section. Sliding is nice, snap on canvas lighter. Steering in the rain is done sitting down. In the sun standing with head and shoulders through hole in cabin top.

And I have said that a FL 33 would be a great idea. Picking up what Jacques said about the Rangeboat - it is also too damned expensive. If Nigel sold the plans you would probably see a few more on the water. It is strip planked so a relatively easy build.

Cheers
Tony

Tony, if the submissions were more frequent and the utilization by the desingers was a tad higher, and the forum was a bulletproof vBulletin, you would be top dog.

I think a sitting room head, with a tip-up or pop-up phone booth for the shower, would work out well. I am with you on the stinking thing (last trip to the ocean we spend a total of 2 hrs on resupply missions on shore, the other 94 hrs on board a 21' fishing boat. Shower free....)

Im with you on the lack of rangeboats. Nigel wields a pencil well, but those are PRICEY boats.

E

For around $25 US, you can get an an inflatable "Sun Shower" enclosure for showering on deck, or you could build one yourself. Build an anchoring arm that slips into a free rod holder and you're good to go. If you wanted to be a little more risque, but fashionable, you could build one out of aluminum and Sunbrella fabric, stretched like a LaFuma chair and make it foldable. Tuck it out of the way somewhere when not in use. Either one would be an easy solution in good weather.

MadRus wrote:For around $25 US, you can get an an inflatable "Sun Shower" enclosure for showering on deck,...Either one would be an easy solution in good weather.

If it rains you could stand naked on the deck with a bottle of soap...

Yeah I forgot about these tent things. More on showering - there is a shower in every marina.

or

If you aren't in a marina just shower on the swim platform - we promise not to peek!

Tony

Tony, some of the best days to cruise in the PNW are when its a high of 50, low of 38F. Not exactly outside-shower weather.

E

OK! We need some input from Toni_V on the FL26 layout now - maybe we can get a sauna in there? So then the showers outside would be at just the right temperature!

Tony

jacquesmm wrote:There is hope on the horizon: crude oil is going up and we may not be able to afford gas guzzlers anymore.

From your lips to God's ears. Well, Allah's ears, maybe. I see figures like 5-8 gallons/hour running time and my feet sweat. Like you say, people just don't go out on the water instead. It's crazy.

MadRus wrote:For around $25 US, you can get an an inflatable "Sun Shower" enclosure for showering on deck, or you could build one yourself.

Tania Aebi had an article somewhere--Good Old Boat? Sailnet.com?--where she put a sun shower in an acrylic-covered box on deck and plumbed it through to the head. Presto, a private hot water shower!

kiwi wrote:OK! We need some input from Toni_V on the FL26 layout now - maybe we can get a sauna in there? So then the showers outside would be at just the right temperature!

Tony

Heh, I don't think there's enough height . A sauna would be must have on a boat like that - I don't like swimming in cold water.

However It's pretty freshing to dip to ice hole in winter. Nice feeling of warmth when you came back up .

And thank's for the kind words earlier, I like to fiddle with designs but I'm not really a designer.

About the hull speed issue - it's not really an issue in here. The traditional two pointer boat is called "fiskari" and they can go nive speeds with little effort.
Usual measures are:
-Lenght 26-33 ft
-Width 6.5-11 ft

And they'll be powered by 20-100 hp engine which will give 10-18 knots of speed. At 60 years ago the same models were powered by 1-2 hp engines to go at hull speed.

There's no magic, hull is rockerless, narrow at waterline while wide an top. It's going nicely as long it's kept light and without heavy top structures. Nowadays the same boats are mostly heavier with cabins and wider to give more stability. So slower.

If Froude would have measured these boats too, I think there wouldn't be hull speed concept like we know these days...

It's been about 15 years ago or so I was tied up at the slips of Lower Granite Damn on the Snake river. It was a pleasant evening around 9 or 10 PM when it began to rain. I was sitting under the canvas thinking about turning in when on a boat that was close to 35 ft. with a long pulpit sticking out over the water the couple began to shower. It was a terrible thing I did, but couldn't help myself. I watched. Next morning inside the marina eating breakfast they appeared. "Nice refreshing rain last night" he said. "Yes it was," I said with a guilty grin. She flushed and as soon as they finished breakfast they cruised downstream.
The boating life is good. Sometimes even memorable.
Duke

Hah, nice. And behind Lower Granite no less! Its beautiful up in that stretch, all along the Snake. I am a big fan of Llyons Ferry, myself....

E

Spending time on the Snake and then into the Columbia during the Salmon and Steelhead season is my favorite. Once went from Lower Granite down the system through the locks spent a couple of days at Ilwaco. Wish there had been video then. I had only super 8. Its still nice to look back.

Hope to return to all that some day. Duke