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Old 12-27-2010, 01:25 PM   #21
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RE: Conventional or POD Drives?

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Marin wrote:* I have read--- but I could well be mistaken--- that the pod drives as used on the GB are designed to shear off rather than rip a big hole in the bottom of the boat.*
-- Edited by Marin on Monday 27th of December 2010 01:45:35 PM
That is in fact true but one of the first Zeus Drives to actually hit something tore the whole unit out of the boat.* And then the finger pointing started.* The boat builder said the it was the fault of the drive not braking off as they were suppose to and Zeus said the the hull was not constructed correctly around the drive and that is why it gave way before the drive could break.*

I'm not sure how that deal was finally resolved.* But as you pointed out what if the boat that struck the can didn't have Zeus drives but instead had twin screws*and stabilizers God knows what that bill would have looked like.

Bottom line is you are not suppose to hit solid objects with props or drives.

A friend of mine was on a sail boat in Fort Lauderdale*FL in Jan of 06*waiting for a window to cross to the Islands.* He watched*as the Queen Mary was pulling out of*the pier*heading out.* But*as it got out to the end of the jetty it cut the corner a bit short.* After the tugs got her back to the dock they worked on her around the clock for two and one half days.* She carries*eight complete props up on the*fore deck and*one was*changed out in the water*right at the pier.*There was additional damage to the pod*so she continued on at reduced speed until the pod itself could be fixed once back in Europe.*

So S**t happens even to the big ones.
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Old 12-27-2010, 10:29 PM   #22
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RE: Conventional or POD Drives?

Mike:

Regarding your "Where's my flying car?". . .Here's a link to song my friend John C. Wiseman wrote. It got an honorable mention in the John Lennon songwriting competition. Doesn't answer the question, but it'll bring a smile to your face.


Jeff Wolf


Link to "The Future Isn't What It Used To Be"

http://www.Minstrosity.com/Future.mp3
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Old 12-28-2010, 06:41 AM   #23
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RE: Conventional or POD Drives?

JD,
I really don,t know what would have happened to a twin screw if it had hit that buoy,which was probably submerged when the Sabre hit it. I do know that looking at that buoy and the incredible amount of drift over the next 4 days, I was glad of my single screw tucked in behind a keel.
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Old 12-28-2010, 07:02 AM   #24
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RE: Conventional or POD Drives?

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Jon wrote:

JD,
I really don,t know what would have happened to a twin screw if it had hit that buoy,which was probably submerged when the Sabre hit it. I do know that looking at that buoy and the incredible amount of drift over the next 4 days, I was glad of my single screw tucked in behind a keel.
Jon
The Ten-Tom was built and maintained for commercial traffic.* While the navigation on* it is fairly easy, the piloting requires constant attention.* To* me it is not a pleasure cruise.

When a boat in deep water*with POD drives hits a submerged log and breaks off, you had better hit the MOB button to mark the spot.* There will probably be some never retrieved.* A crane would probably be needed to lift it.* Would this be considered salvage?

*
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Old 12-28-2010, 03:25 PM   #25
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Conventional or POD Drives?

Here a couple of em for sale.* *< grin >

http://www.harlowmarine.com/index.php?a ... :111:828:3

http://www.harlowmarine.com/index.php?a ... :111:797:3<br clear="all" />


-- Edited by Phil Fill on Tuesday 28th of December 2010 04:51:27 PM
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Old 12-28-2010, 03:42 PM   #26
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RE: Conventional or POD Drives?

Quote:
Phil Fill wrote:

Here a couple of em for sale.* *< grin >

http://www.harlowmarine.com/index.php?a ... :111:828:3

http://www.harlowmarine.com/index.php?a ... :111:797:3<br clear="all" />
Takes alot of the negatives away!

*
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Old 12-28-2010, 03:52 PM   #27
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RE: Conventional or POD Drives?

Here a vedeo of them working.<a href="
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Old 12-28-2010, 04:37 PM   #28
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RE: Conventional or POD Drives?

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Here a vedeo of them working.<a href="
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Old 01-10-2011, 12:56 PM   #29
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RE: Conventional or POD Drives?

A guy I know last week was having a captain take his boat from CT to FL.* It is a 36' flybridge sedan cruiser.* The captain ran it aground just above St. Augustine at about 20 knots.* Fortunately, most of the FL ICW is soft bottom.* He was hard aground, but the tide lifted him off.* The damage was a dinged prop.

Any body have an idea to the damage that would have been done to a pod drive?* Do you think that it would have broken off?
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Old 01-10-2011, 01:24 PM   #30
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RE: Conventional or POD Drives?

If you have deep enough pockets, pod drives on a fast trawler is probably the way to go.* The jury is still out on the long term costs of owning a pod driven boat.* A lot of folks on this forum are tooling around in 20 to 30+ year old boats.* If I fast forward 25 years to the point where the pod boats become more affordable, I probably would still be reluctant to commit to one for fear of having some major repair or upgrading costs compared to conventional drive systems.

That said, if you have the bucks and keep the boat only while it is in its prime- Why not enjoy the benefits of pods.

Jealous but Happy**** JEP
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Old 01-10-2011, 01:35 PM   #31
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RE: Conventional or POD Drives?

I see no reason why pod drives shouldn't enjoy the same reliability over time as conventional drives. They will most likely require some different types of maintenance to a conventional drive, but I see no reason to believe they will be more costly in the overall scheme of things than conventional drives. How many posts do we see about conventional drive systems where they "make a funny rumbling," "the shaft vibrates," "the shaft logs leak too much, " and on and on and on. I don't think pod drives will be any different and by eliminating the long drive shafts and supporting structures and bearings and rudders they actually may require less maintenance and repair.

In my opinion, the comparison between pod drives (well designed and well built) to the drive systems in our boats today is like comparing a Mercedes to a guy rolling a hoop down the road with a stick
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Old 01-10-2011, 01:42 PM   #32
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RE: Conventional or POD Drives?

Pod drives
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Old 01-10-2011, 01:49 PM   #33
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RE: Conventional or POD Drives?

Marin,
I think, in my opinion, the comparison between pod drives, to the drive systems in our boats, that would be used on the Loop and the Bahamas ( with the fun of gunk holing and occasional groundings) is like comparing a Lamborghini with a (slightly dented) Toyota Landcruiser
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Old 01-10-2011, 01:53 PM   #34
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RE: Conventional or POD Drives?

Quote:
Jon wrote:

Marin,
I think, in my opinion, the comparison between pod drives, to the drive systems in our boats, that would be used on the Loop and the Bahamas ( with the fun of gunk holing and occasional groundings) is like comparing a Lamborghini with a (slightly dented) Toyota Landcruiser
Jon

Yeah, I would not go quite as far as Marin, on the hoop and stick thing!
*
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Old 01-10-2011, 01:57 PM   #35
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RE: Conventional or POD Drives?

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RickB wrote:

Pod drives
Rolls can't seem to get anything right these days......

*
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Old 01-10-2011, 02:04 PM   #36
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Conventional or POD Drives?

Quote:
Jon wrote:

Marin,
I think, in my opinion, the comparison between pod drives, to the drive systems in our boats, that would be used on the Loop and the Bahamas ( with the fun of gunk holing and occasional groundings) is like comparing a Lamborghini with a (slightly dented) Toyota Landcruiser
Jon
I don't agree with that at all.* There is no reason a twin-engine pod-drive boat can't be designed to provide the same degree of protection to the drive system as converntional twin-engine boats have--- in other words, a keel or some other component to hit first.* Running a conventional shaft, struts, prop and rudder into the bottom is going to leave you every bit a screwed as hitting the bottom with a pod drive.

I'll go along with the notion that a single engine boat with its prop and rudder behind the keel could be less vulnerable to a soft grounding than a twin engine anything (other than a jet boat).

But I've always maintained that running aground is totally a function of a dumba*s driver and not an automatic consequence of the boat's hvaeing one, two, or ten engines or having shafts, props, and rudders or* I/O drives or pod drives.* But maybe I'm wrong......




-- Edited by Marin on Monday 10th of January 2011 03:07:32 PM
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Old 01-10-2011, 02:25 PM   #37
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RE: Conventional or POD Drives?

Well** ...if the builder would take the trouble to remove the center keel and install two keels along the propeller shafts of the twin the twin would have as much protection as the single. Furthermore the twin keeled craft would not lay over on her side when high and dry. Then w hydraulic thrusters fore and aft, plus the twin screws the pods would be cost effective.
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Old 01-10-2011, 02:26 PM   #38
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RE: Conventional or POD Drives?

Marin,
I guess I'm one of them dumb a?s drivers who ain't happy unless they're trying to get off the beaten track,and boldly go where no dumb a?s has ever gone before!
I couldn't imagine cruising if I thought a slow speed grounding was going to end the cruise - that's why we have tide tables,kedge anchors and shovels.
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Old 01-10-2011, 02:26 PM   #39
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Conventional or POD Drives?

The question was, " would the pod drive break off at a 20 knot soft grounding".* I am not defending any system.* Just trying to figure out what I would buy in the future.* I was surprised that there was so little damage done at that speed.

Grounding is a real problem as most of the areas south of the Chesapeake* have allot of shallow water around.* Fortunately, most of it is soft bottom.* Much of the ICW runs behind inlets that make the channel subject to shoaling.* Our bottoms shift with the currents and storms.*Soft groundings are commonplace.* I just want to know what happens.

-- Edited by Moonstruck on Monday 10th of January 2011 03:28:19 PM
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Old 01-10-2011, 02:28 PM   #40
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RE: Conventional or POD Drives?

Quote:
nomadwilly wrote:

Well** ...if the builder would take the trouble to remove the center keel and install two keels along the propeller shafts of the twin the twin would have as much protection as the single.
Wouldn't that negate much of the efficiencies realized by having the pod props out in clear water?

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