Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-28-2019, 03:38 AM   #21
Guru
 
AusCan's Avatar
 
City: Adelaide
Vessel Name: Kokanee
Vessel Model: Cuddles 30 Pilot House Motor Sailer
Join Date: Jul 2012
Posts: 3,122
Generally, a full displacement boat will roll more than a hard chined semi-displacement boat when in a beam sea. Although the tendency to roll is more, it is a softer roll without the snap action that a hard chined boat gets in a side on swell.

Some like it, some don't.
__________________
Advertisement

AusCan is offline   Reply With Quote
Old 01-28-2019, 07:37 AM   #22
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 21,364
"OK, so basically since a full displacement type hull cannot get on plane due to its design, an engine that has less HP is sufficient to push through water were as a Semi Displacement hull that can partially get up on plane needs this extra HP to get up on plain although its not very fuel efficient to do so..do I have this right? "

Close , the rounded hull Can be pushed up on its bow wave , it just takes MASSIVE HP or a skinny boat that makes a smaller bow wave.

During WWI good speed was obtained with triple engines , a massive fuel supply and a WL L/B ratio of better than 6-1.

Herrishoffs "Marco Polo" series of motor sailors were able to cruise at 10K as they were fine on the waterline.

For cheap travel the full displacement boat run at about the SQ RT of the WL (not hull speed) only takes about 3 HP per ton of displacement .

2240lbs per displacement ton. Hull speed can be 5HP per ton or more.

So a 44,800 boat will need only 20HP in the water , to cruise , a bit over a gallon an hour.

Larger engines are installed so alternators , bilge pumps and other goodies can be engine driven.

As non industrial engines are peak rated , not cont rated.

,A cruiser can be fitted with an engine rated with over "100" hp , although in most cases it uses 2 or 3GPH , or 30 -55HP long term.

IF the eng. mfg. has a table of rpm/hp ratings from M1 to M4 it is usually an industrial engine.

IF not the engine will be OK of only loaded to 1 hp for every e CI of displacement , or so.

Good hunting.
__________________

FF is offline   Reply With Quote
Old 01-28-2019, 08:04 AM   #23
Dauntless Award
 
Wxx3's Avatar
 
City: Wrangell, Alaska
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,800
Quote:
Originally Posted by jefndeb View Post
Is it just me or is this an unbelievably beautiful boat....good price as well!!

View Yacht - Kadey-Krogen Yachts, Inc. : Kadey-Krogen Yachts, Inc.
It does sound very good.
I like the two head model and this boat also has a lot of extras that make it very nice. I think it's a good, fair price, as long a it is as described.

I would like to know what her previous name was, if anyone knows.

One thing I will add about semi planing or semi displacement hulls.
If i have 28 miles to go. With my full displacement hull, I know it's going to take 4 hours. Doesn't matter what the wx is going to do, hurricanes, tornadoes, Svr CAT, doesn't matter, it's 4 hours and we must be prepared.
But i needed that full efficiency, 4.15 nm/gal, to cross oceans.

If i wasn't crossing oceans and most aren't, a good case can be made that it's nice, sometimes convenient, certainly more comfortable to have the option to make that 28 mile trip in 2 hours or less.

It's one of the reasons SD boats are 98% of the market.
__________________
Richard on Dauntless,
New York

a Kadey Krogen 42 currently: https://share.garmin.com/dauntless
Blog:
https://dauntlessatsea.com
Wxx3 is offline   Reply With Quote
Old 01-28-2019, 08:32 AM   #24
Dauntless Award
 
Wxx3's Avatar
 
City: Wrangell, Alaska
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,800
Quote:
Originally Posted by AusCan View Post
Generally, a full displacement boat will roll more than a hard chined semi-displacement boat when in a beam sea. Although the tendency to roll is more, it is a softer roll without the snap action that a hard chined boat gets in a side on swell.

Some like it, some don't.
And with my Kadey Krogen, the rolling doesn't take any power, though the rolling itself is a function of speed.

In other words, at a given rpm and power, the speed and therefore consumption is the same whether rolling or not (not stabilized).
And in the same beam seas, the faster I go, the more it rolls.
__________________
Richard on Dauntless,
New York

a Kadey Krogen 42 currently: https://share.garmin.com/dauntless
Blog:
https://dauntlessatsea.com
Wxx3 is offline   Reply With Quote
Old 01-28-2019, 08:55 AM   #25
Guru
 
City: gulf coast
Join Date: Jun 2014
Posts: 3,366
Quote:
Originally Posted by jefndeb View Post
OK, so basically since a full displacement type hull cannot get on plane due to its design, an engine that has less HP is sufficient to push through water were as a Semi Displacement hull that can partially get up on plane needs this extra HP to get up on plain although its not very fuel efficient to do so..do I have this right?
Yes, but at slower speeds The SD will use similar fuel as the FD hull. IMO the option of going fast when desired is nice to have. You get to decide.
bayview is offline   Reply With Quote
Old 01-28-2019, 07:42 PM   #26
Senior Member
 
Mikala's Avatar
 
City: New Smyrna Beach, FL
Vessel Name: Mikala
Vessel Model: DeFever 48
Join Date: Jan 2019
Posts: 210
The KK42 the OP is referring to is under contract.
Mikala is offline   Reply With Quote
Old 01-28-2019, 07:52 PM   #27
Guru
 
tiltrider1's Avatar
 
City: Seattle
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 2,259
SD hulls have a lot more drag than FD hulls. For most of not cruising oceans the difference is insignificant. However, that extra .5 nautical mile per gallon could add up to 500 more miles of range.
tiltrider1 is online now   Reply With Quote
Old 01-28-2019, 08:31 PM   #28
Veteran Member
 
City: Barnegat Bay
Vessel Name: Hey Jude
Vessel Model: KK42-94
Join Date: Aug 2014
Posts: 75
"I would like to know what her previous name was, if anyone knows. "

Richard... Krogen Cruisers is showing her previous names were:

Ben Addiction; Graves End, Summers Beginning II
__________________
I'll never grow up, nope, not me.
... Peter Pan
KapnKarl is offline   Reply With Quote
Old 01-28-2019, 08:34 PM   #29
Veteran Member
 
SpaceCadet's Avatar
 
City: New Bedford, MA
Vessel Model: Currently Boatless
Join Date: Nov 2018
Posts: 26
Quote:
Originally Posted by jefndeb View Post
Is it just me or is this an unbelievably beautiful boat....good price as well!!

View Yacht - Kadey-Krogen Yachts, Inc. : Kadey-Krogen Yachts, Inc.
Definitely a very beautiful boat and appears to be well preserved. Whether it is well priced is up to you - it all gets very subjective. My only hesitation is with teak planked decks. A KK is not one of those generic Asian trawlers known for leaky/soft decks. But sooner or later they’ll all need more work regardless of the build quality. 33 years is a long time. But that’s just (nervous) me with limited funds.

It’s beautiful and maybe perfect for you!
SpaceCadet is offline   Reply With Quote
Old 01-28-2019, 09:31 PM   #30
Guru
 
AusCan's Avatar
 
City: Adelaide
Vessel Name: Kokanee
Vessel Model: Cuddles 30 Pilot House Motor Sailer
Join Date: Jul 2012
Posts: 3,122
Quote:
Originally Posted by Wxx3 View Post

And with my Kadey Krogen, the rolling doesn't take any power, though the rolling itself is a function of speed.

And in the same beam seas, the faster I go, the more it rolls.
Interesting.
With my displacement boat the rolling is slightly reduced with more speed. This may be the bilge keels stabilising the roll.
AusCan is offline   Reply With Quote
Old 01-28-2019, 10:48 PM   #31
Senior Member
 
bogranjac1's Avatar
 
City: =
Vessel Name: Nimiane
Vessel Model: Finn 8
Join Date: Jul 2014
Posts: 342
My boat has 'rolling chocks' and experiences easily 50% less roll since fitting. I wonder why so many discount the benefits of these simple additions without trying them for themselves and seeing with their own eyes. Almost any mug can easily make and fit them. I did.
__________________
Sea the swells out on the ocean
All a-movin' in a rhythm, If I didn't have to be here
I would surely be-ee there with them
song-'bali waters' from film-'morning of the earth'
bogranjac1 is offline   Reply With Quote
Old 01-29-2019, 04:41 AM   #32
Dauntless Award
 
Wxx3's Avatar
 
City: Wrangell, Alaska
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,800
Quote:
Originally Posted by bogranjac1 View Post
My boat has 'rolling chocks' and experiences easily 50% less roll since fitting. I wonder why so many discount the benefits of these simple additions without trying them for themselves and seeing with their own eyes. Almost any mug can easily make and fit them. I did.
I'm sure you and AusCan are right.
When I had the option to have them added in Ireland for the more than reasonable price of $2500 while having my bottom redone, I debated doing it.
I also wanted the boat to be able to sit more upright if in a drying harbor.
Certainly a lot of European work boats have them.

Alas, in the limited time i had to make a decision, I opted against, because:

1. I knew and accepted how the boat handled. The devil i know was better ...

2. If they had no downside, then why didn't James Krogen put them on the boat in the first place?

3. It certainly wasn't going to add to my fuel efficiency. How much it would hurt was a significant issue. Even 10% would be unacceptable to me.
If I knew the number was only 1% , i would have done it, but not unknowing.

3. $2500
__________________
Richard on Dauntless,
New York

a Kadey Krogen 42 currently: https://share.garmin.com/dauntless
Blog:
https://dauntlessatsea.com
Wxx3 is offline   Reply With Quote
Old 01-29-2019, 07:41 AM   #33
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 21,364
"Yes, but at slower speeds The SD will use similar fuel as the FD hull."

The SD hull would take 10% to 15% more energy to push at displacement speeds if both hulls had the same displacement.
The 2 engines or bigger single is also less efficient , by at least 5%.

The fuel burn increase is not noticed as the SD boat is usually built far lighter so it can be pushed on top of the water.

The SD boaters claim they can outrun the storms , so light construction is OK.

YRMV
FF is offline   Reply With Quote
Old 01-29-2019, 08:50 AM   #34
Guru
 
Dougcole's Avatar
 
City: Carrabelle, FL
Vessel Name: Morgan
Vessel Model: '05 Mainship 40T
Join Date: Jan 2008
Posts: 1,676
Quote:
Originally Posted by kchace View Post
The Mainship has the 380hp so they can say it has a top speed of 16kts which sounds really great. The reality is that the fuel mileage at 16kts is so poor that nobody except the rich would run it at that speed for any length of time. We're talking .7mpg vs 2-3mpg. If one only runs a few miles to the sand bar and back, 16kts is great. For anybody doing long range cruising, the .7mpg is prohibitive.

The KK has a much more realistic HP that is very adequate for the type of use the boat was intended.

Keep in mind that most trawlers in the 4x' range need only about 60hp to run at 6-8mph which is the speed range that most are run at.

Ken

I thought I'd chime in on this thread since I have a mainship 400, albeit with twins, so it is a faster boat and perhaps a bit more efficient at higher speeds. Though at WOT our boat will run 19 knots, it's really pushing it to do that. It's much happier at around 15 knots. Sixteen knots is possible but is above the sweet spot. At 2800-2900 rpm we get about 1.2 nmpg. Not great, but much better than .7, and not some crazy fuel burn that only the super wealthy can afford.


That said, I think the general info in this thread is quite accurate as to the differences between HP and SD vs FD. I agree with most everything said here.


As far as motion goes, our old boat, a 1973 Gulfstar 36, was a round chine boat built on a sailboat hull. Our main issue with it was how much it rolled, it was not a comfortable boat in any sea over two feet. It would roll the gunnels under in a 5' beam sea. The hard chine Mainship is much, much more stable at slow speeds in bigish seas. I've never seen the "snap roll" thing with our boat that often gets quoted, though admittedly, I've never had it out in anything bigger than about 6-7' and that was mostly on the stern. My feeling is that what keeps Mainships and their ilk from being ocean crossers is their build quality and lack of range rather than the comfort/safety aspect of the shape of their hull. A friend has a 70' American Yacht sportfish (lucky dude) that they use to fish all over the world. They have taken it through the Panama Canal twice and it has been to the Galapagos. It's a hard chine boat. Big engines, big fuel tanks, big budget.



To me safety encompasses many things. Perhaps a rolly boat isn't going to capsize, but if it makes it so hard to move around that you almost have to crawl and it is rolling the dishes out of the sink (actually happened on our Gulfstar) it doesn't seem very safe to me.
Dougcole is offline   Reply With Quote
Old 01-29-2019, 02:28 PM   #35
Guru
 
kchace's Avatar
 
City: Brookline, NH
Vessel Name: Blue Heaven
Vessel Model: Albin 43 classic double cabin, twin 135 Lehmans
Join Date: Sep 2013
Posts: 1,986
Quote:
Originally Posted by Dougcole View Post
I thought I'd chime in on this thread since I have a mainship 400, albeit with twins, so it is a faster boat and perhaps a bit more efficient at higher speeds. Though at WOT our boat will run 19 knots, it's really pushing it to do that. It's much happier at around 15 knots. Sixteen knots is possible but is above the sweet spot. At 2800-2900 rpm we get about 1.2 nmpg. Not great, but much better than .7, and not some crazy fuel burn that only the super wealthy can afford.


That said, I think the general info in this thread is quite accurate as to the differences between HP and SD vs FD. I agree with most everything said here.


As far as motion goes, our old boat, a 1973 Gulfstar 36, was a round chine boat built on a sailboat hull. Our main issue with it was how much it rolled, it was not a comfortable boat in any sea over two feet. It would roll the gunnels under in a 5' beam sea. The hard chine Mainship is much, much more stable at slow speeds in bigish seas. I've never seen the "snap roll" thing with our boat that often gets quoted, though admittedly, I've never had it out in anything bigger than about 6-7' and that was mostly on the stern. My feeling is that what keeps Mainships and their ilk from being ocean crossers is their build quality and lack of range rather than the comfort/safety aspect of the shape of their hull. A friend has a 70' American Yacht sportfish (lucky dude) that they use to fish all over the world. They have taken it through the Panama Canal twice and it has been to the Galapagos. It's a hard chine boat. Big engines, big fuel tanks, big budget.



To me safety encompasses many things. Perhaps a rolly boat isn't going to capsize, but if it makes it so hard to move around that you almost have to crawl and it is rolling the dishes out of the sink (actually happened on our Gulfstar) it doesn't seem very safe to me.

Sorry if my post seemed insulting to your boat, it was not intended that way. I like the Mainships and almost bought one. I did generalize somewhat regarding MPG but have read many Mainship tests and while they're often reported to get about 1 to 1.x mpg at approximately hull speeds, I believe the fuel usage at higher speeds would be cost prohibitive for some folks. My whole point was that while a higher hp engine and higher top speed sounds good, in reality the fuel required for the higher speeds will turn some people off.



Ken
kchace is offline   Reply With Quote
Old 01-29-2019, 03:30 PM   #36
Veteran Member
 
City: Holland, Michigan
Vessel Name: Emerald Isle
Vessel Model: Nordic Tugs 32
Join Date: Jun 2017
Posts: 44
Maybe this should be in a different thread, but I've a comment on the "cost of speed". I've calculated this for several vehicles, including my Nordic Tugs trawler. Here's the jist of it: If you are going a given speed and burning a given amount of fuel, how much would it cost if I changed the speed a little. Cost is in term of dollars per hour saved. In other words, what would it cost to get there an hour sooner? It is essentially the slope of the speed and fuel consumption lines. For my Nodic Tugs 32 at 1200 rpm and 6.8 kts it is $2 per hour. At 1300 and 7.4 kts it is $10 per hour. At the very top end, at 2500rpm and 16.2 kts it is $36 per hour saved. I would very much like any information anyone has on a similar boat, hopefully including actual fuel consumption data. My information is from a sheet I found on the boat, source and accuracy unknown. Thanks in advance.
garycasey is offline   Reply With Quote
Old 01-29-2019, 03:57 PM   #37
Guru
 
BandB's Avatar
 
City: Fort Lauderdale
Join Date: Jan 2014
Posts: 19,621
Quote:
Originally Posted by garycasey View Post
Maybe this should be in a different thread, but I've a comment on the "cost of speed". I've calculated this for several vehicles, including my Nordic Tugs trawler. Here's the jist of it: If you are going a given speed and burning a given amount of fuel, how much would it cost if I changed the speed a little. Cost is in term of dollars per hour saved. In other words, what would it cost to get there an hour sooner? It is essentially the slope of the speed and fuel consumption lines. For my Nodic Tugs 32 at 1200 rpm and 6.8 kts it is $2 per hour. At 1300 and 7.4 kts it is $10 per hour. At the very top end, at 2500rpm and 16.2 kts it is $36 per hour saved. I would very much like any information anyone has on a similar boat, hopefully including actual fuel consumption data. My information is from a sheet I found on the boat, source and accuracy unknown. Thanks in advance.
The offset is cost of slow or value of time. To some, getting to a destination and having more time there isn't important. A day on the water is a day on the water. To others, it's very important. To a family boating on the weekend, it's priceless. To someone with 2 weeks vacation with their family it's of tremendous value. Looking at the above, I'd never use per hour savings as that assumes you're not intending to go as far. Rather I'd use the amount saved per mile. Ultimately you'd end up with something more like this, just arbitrary numbers I'm using.

10 knots, 5 gph, $4 diesel, cost per mile $2
15 knots, 15 gph, cost per mile $4
20 knots, 30 gph, cost per mile $6

So per 1000 miles,
Cost at 10 knots $2000, 100 hours
Cost at 15 knots $4000, 67 hours
Cost at 20 knots $6000, 50 hours

Cost 15 knots cost $2000 extra, saves 33 hours.
20 knots cost $4000 extra, saves 50 hours.

If you were financially analyzing it then is the value of 33 hours as much as $2000, $61 per hour. Is 50 hours worth $4000, $80 per hour.

Not to the casual boater who isn't in a hurry. However, to the doctor spending his only two weeks of the year with his family, definitely is.

Coming from my background, I can't stop valuing my time highly. I'm use to thinking that way.
BandB is online now   Reply With Quote
Old 01-29-2019, 04:46 PM   #38
Guru
 
ranger42c's Avatar
 
City: Maryland
Vessel Model: 42' Sportfish
Join Date: Aug 2013
Posts: 5,362
Quote:
Originally Posted by kchace View Post
I did generalize somewhat regarding MPG but have read many Mainship tests and while they're often reported to get about 1 to 1.x mpg at approximately hull speeds, I believe the fuel usage at higher speeds would be cost prohibitive for some folks.

Seems low, to me. We can push close to 2 NMPG at about 7 kts, closer to 3 at 6.5 kts... although that's using nominal Cummins figures, not measured fuel flow.

-Chris
__________________
South River, Chesapeake Bay
ranger42c is offline   Reply With Quote
Old 01-29-2019, 09:58 PM   #39
Guru
 
kchace's Avatar
 
City: Brookline, NH
Vessel Name: Blue Heaven
Vessel Model: Albin 43 classic double cabin, twin 135 Lehmans
Join Date: Sep 2013
Posts: 1,986
Quote:
Originally Posted by ranger42c View Post
Seems low, to me. We can push close to 2 NMPG at about 7 kts, closer to 3 at 6.5 kts... although that's using nominal Cummins figures, not measured fuel flow.

-Chris
I would have no idea but this is what I read in 2 different tests.
kchace is offline   Reply With Quote
Old 01-29-2019, 11:51 PM   #40
Guru
 
Simi 60's Avatar
 
City: Queensland
Vessel Model: Milkraft 60 converted timber trawler
Join Date: Jul 2016
Posts: 3,085
Quote:
Originally Posted by FF View Post

For cheap travel the full displacement boat run at about the SQ RT of the WL (not hull speed) only takes about 3 HP per ton of displacement .

2240lbs per displacement ton. Hull speed can be 5HP per ton or more.

So a 44,800 boat will need only 20HP in the water , to cruise , a bit over a gallon an hour.

Larger engines are installed so alternators , bilge pumps and other goodies can be engine driven.

As non industrial engines are peak rated , not cont rated.

,A cruiser can be fitted with an engine rated with over "100" hp , although in most cases it uses 2 or 3GPH , or 30 -55HP long term.

IF the eng. mfg. has a table of rpm/hp ratings from M1 to M4 it is usually an industrial engine.

IF not the engine will be OK of only loaded to 1 hp for every e CI of displacement , or so.

Good hunting.

Trick will be getting a decent engine.
I doubt a 1.9 litre 75hp yanmar or similar will do as well as a 7 litre 5lw Gardner for example
Attached Thumbnails
Screenshot_2019-01-30-14-54-24~01~01.jpg  
__________________

Simi 60 is online now   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 07:14 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×