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As many know, I have been using a Torqeedo Travel 1003 on my H-Boat (27' 3200 lbs.) for about 3 years. I've been happy with it. I have been eyeballing their 5 HP pod drive, but the cost has put me off some - $8400 plus tax, shipping and installation. I'm looking into the ePropulsion pod drive (6 HP), and the cost is $2,000+ less than the Torqeedo. I've got a lot of questions, and there are probably important ones that haven't occurred to me, so I thought I would start this thread and ask for y'all's advice.

I confess that I can live with the Torqeedo OB; the Pod is a "nice to have" not a "gotta have." I think the extra  power would be nice if conditions get nasty. The Torqeedo's 3 HP is not robust. Ease and convenience are a consideration. I store the Torqeedo in the cabin, and schlep it out and back when sailing. I also schlep a battery home for re-charge, although not every time. Aesthetics are also a consideration. An OB motor and bracket do nothing for a boat's appearance.

A pod drive would solve these problems, I think. But there would be new things to worry about. Anti-fouling. Anodes. Continuous immersion. What to do if the motor breaks down - the motor is in the pod. What kind of batteries - eProp has a Li-ion with 3042 Wh for $3K , and a LiFePO4 battery with 4096 Wh for $2K. 

The Torqeedo brand has a mixed reputation. I've had a good experience. I don't know anything about ePropulsion. The closest dealer is Annapolis Hybrid Marine. So far they have been responsive and forthcoming.

Thanks in advance.

B.C.

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Crash, I truly appreciate your concern. One of the things I'm having the yard do is to remove the OB bracket and restore the transom to its virginal innocence. I hated putting the bracket on it 6+ yea

That's a fallacy promoted by makers of electric propulsion. 1 HP = 746 Watts = 0.746 kW. That is the definition of what a HP is! The output of outboard motors is measured at the prop shaft so the

Thank you, I like her

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With the rate this field is developing, my suggestion would be to live with your Torqeedo until it craps out, which it inevitably will. Then take a look at what's available and at what cost. Designs are getting better, batteries are getting better and cheaper, and competition is entering and driving system prices down. I don't think that in two years the situation will be night and day but it might make a 25% difference in price, power, or both.

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43 minutes ago, IStream said:

With the rate this field is developing, my suggestion would be to live with your Torqeedo until it craps out, which it inevitably will. Then take a look at what's available and at what cost. Designs are getting better, batteries are getting better and cheaper, and competition is entering and driving system prices down. I don't think that in two years the situation will be night and day but it might make a 25% difference in price, power, or both.

Very good advice. We lived with our old solar PV panels for maybe a little longer than was conducive to restful sleep, battery health, or domestic bliss. But waiting until the last minute (read: this Fall) meant we got new panels with 2.5 times the output at a laughably low cost.  There's definitely a crossover point. "Fun to play with" becomes "Nice to have" becomes "What idiot wouldn't?"

171170b3a3b940fea2790d9a4fd6b704.jpg

Nokia 3310 Original

The Best Phones for 2020 | PCMag

 

 

 

13 minutes ago, Bull City said:

I may crap out first.

In which case, problem solved. ;) 

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32 minutes ago, IStream said:

The the question becomes whether your wife or kids would prefer the upgraded boat or the $8400. 

That really is not the question, at least to me.

Even if it were, they will get some stuff that that ain't cash, however, they can consider themselves fortunate that they will not have to dispose of a 60 foot ferro-cement broken dream, and all of the "valuable" accessories that go with it, that are worth pennies on the dollar, maybe less.

That is not a worry to me.

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12 hours ago, nota said:

https://www.sailmagazine.com/gear/epropulsion-alternative-fuel-outboards

 

any one got one or their smaller stuff

I have never seen or heard of one of these

Yup, I have the small ePropulsion with the integrated and demountable battery, the Spirit 1.0 Plus.  I previously had a Torqeedo 1003 for several years, which pissed me off with its whiny gearbox noise, plasticky fittings and temperamental electrical connections.  I was pleased to get rid of it (and a Mariner 6hp) and use the cash to buy the eProp, which has a direct drive, gearless and therefore silent motor and a MUCH bigger battery.

I can’t see where you’re based but eProp have taken off in the UK despite only having a few dealers.  Word has mostly spread by mouth on forums like this as I don’t think that marketing is one of eProp’s strong points.  Their website is fairly clunky and misses the brisk German efficiency (and over-promises) of the Torqeedo website.

if you want to see a side by side comparison of the small Torqeedo and the small eProp, have a look at this website of an agent for both brands, although probably not for much longer! https://nestawayboats.com/shop/epropulsion-spirit-plus-1kw-electric-outboard/.  The comparison is below the first couple of screens.

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13 hours ago, Matagi said:

I'm currently eyeing the Haswing Ventura 

no fancy proprietary gimmicks, apps or voltage like with Torqeedo, but a rather 'open' system, so I can decide which batteries to use.

 

Now that eProp have moved the Spirit outboard battery from 40.7V to 48V,  it too can be run on a variety of batteries.  However, you can’t buy the outboard without its lithium battery - you could probably sell it to someone who needs a spare.

Matagi’s link to the Haswing Ventura page has a toggle (top right) between German and English language versions.  Choose the English version and you get the page......in German.  I don’t take it personally.

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I’ve got the Spirit 1.0 for my inflatable dink. Trade offs are well-known and similar to other electrics: It’s plenty for tooling around an anchorage, and the peace and quiet are wonderful, but it can’t get onto a plane or go more than a few miles at speed. I have neither a talent nor an interest in gasoline engine maintenance, so the fact that it needs literally no maintenance at all is worth the sacrifice. It’s probably the only thing on my boat that hasn’t given me issues at least once since I bought it a couple of years ago.

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I have an eProp Spirit outboard as well. It is more reliable, lighter, and less noisy than the British Seagull that it replaced :P

I'd think the pod drive would be an expensive, if convenient replacement for an outboard. I'd worry a little about longevity, there are signs of corrosion on my Spirit after only one year use (but to be fair, the same can be said of most outboards).

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25 minutes ago, DDW said:

more reliable, lighter, and less noisy than the British Seagull that it replaced 

As is convincing a passing pinniped to take your painter and and tow you to where you want to go.

I've lived with a couple of saildrives for a couple of decades and I suspect the concerns that they bring are similar to a those of a pod drive.

  • seals
  • electrolysis / zincs / isolation / corrosion /  etc.
  • bottom paint / fouling
  • access to the mechanical and electrical bits for maintenance and repair.
  • local parts availability

Presumably they will also add electrical and electronic complications.

That said, I like the idea. The details may take some working out though.

 

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4 hours ago, DDW said:

I'd worry a little about longevity, there are signs of corrosion on my Spirit after only one year use (but to be fair, the same can be said of most outboards).

DDW, are you using it in salt water? I'm in fresh water. 

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I love fresh water. I'm using it in salt. When I had my boat in the Great Lakes everything stayed new for 2 years. We hit the salt just above Quebec City on the St. Lawerence and everything started to corrode like crazy. More corrosion in 2 weeks than in 2 years on the GL. I'd be a lot more confident in it in fresh water. 

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6 hours ago, DDW said:

I have an eProp Spirit outboard as well. It is more reliable, lighter, and less noisy than the British Seagull that it replaced :P

To be fair, a bunch of high explosives playing heavy metal is quieter than a British Seagull.

Or at least the newer Seagulls.  My father had two: a wee 1950s Seagull with lots of brass components, which ran like a jewel ... and a 1970s one with some cheap steel components and hideous din.

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Let's just say they could hear me coming. It is a mid 70's (late model!) Silver Century Plus, with clutch. I bought it from a would be collector, it hadn't run in at least 20 years. After filling it with the oil-gas mixture it runs on, and letting the cork gaskets swell to stem the many leaks, I was disappointed that it did not start on the first winding of the rope. But it did start on the second. Not the most refined mechanism, but one that does not suffer from needing tight clearances and intricate adjustments either. Absolutely reliable thereafter, until retired in favor of the eProp. It is sitting in my shop now, leaking the gear oil/seawater mix contained loosely in the bevel drive. 

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3 hours ago, DDW said:

I love fresh water. I'm using it in salt. When I had my boat in the Great Lakes everything stayed new for 2 years. We hit the salt just above Quebec City on the St. Lawerence and everything started to corrode like crazy. More corrosion in 2 weeks than in 2 years on the GL. I'd be a lot more confident in it in fresh water. 

DDW, do you leave it in the water when not in use?  I recall the user guide/manual recommends taking out of the water and wash with fresh water after each use; we honor that a bit in the breach, but we don't leave it on the dinghy, and we wipe it down with a paper towel wet with bottled water before moving the mothership and generally stow in the aft cabin.

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I don't leave it in the water, but in my use it isn't practical to coddle it much either. It is on the dinghy, on davits on the trawler. When we are out that's where it stays, last year for about 6 months up into Alaska. It gets plenty of fresh water washes in the PNW :lol: but only gets properly washed when put away for the season or maybe rarely at a marina. A fresh water wash after each use isn't happening when the nearest source of fresh water may be a weeks drive away and we use it nearly daily. I guess I should install a watermaker but that is a maintenance nightmare for sure. 

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I've been studying the Torqeedo Pod Drive 2.0 (5 HP) and the ePropulsion 3.0 (6 HP). An all Torqeedo system would probably run about $7,850, while eProp would be less. 

I would like to position the battery in a storage bin under the cockpit and accessible from the cabin. The Torqeedo battery would easily fit, but the eProp NAVY Battery would be tight. The two are the same price, but the Torqeedo has more Watt Hours. So I was thinking of using the Torqeedo battery with the eProp pod. I have a Torqeedo throttle, so I might be able to get a credit for the one that's included with their pod. Unfortunately, the voltages are different: Torqeedo 24v, eProp 48v. So I don't think that will work.

Then I recalled that eProp has another technology, the E Battery that is cheaper than the NAVY Battery,

Here's a comparison of the eProp options:

image.png.f225a62b96c563e47ea3301738e0235f.png

The NAVY Battery (https://www.epropulsion.com/product-page/navy-battery) is a High-performance Li-ion battery. The E80 Battery (https://www.epropulsion.com/product-page/e80-battery) is a 4096 Wh LiFePO4 battery. Different technology, but I don't know what the difference is.

I like the idea that the E80 has more Watt hours, and that it is more compact, but it is 36 lbs. heavier.

So what do y'all think so far?

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2 hours ago, Bull City said:

I've been studying the Torqeedo Pod Drive 2.0 (5 HP) and the ePropulsion 3.0 (6 HP). An all Torqeedo system would probably run about $7,850, while eProp would be less. 

I would like to position the battery in a storage bin under the cockpit and accessible from the cabin. The Torqeedo battery would easily fit, but the eProp NAVY Battery would be tight. The two are the same price, but the Torqeedo has more Watt Hours. So I was thinking of using the Torqeedo battery with the eProp pod. I have a Torqeedo throttle, so I might be able to get a credit for the one that's included with their pod. Unfortunately, the voltages are different: Torqeedo 24v, eProp 48v. So I don't think that will work.

Then I recalled that eProp has another technology, the E Battery that is cheaper than the NAVY Battery,

Here's a comparison of the eProp options:

image.png.f225a62b96c563e47ea3301738e0235f.png

The NAVY Battery (https://www.epropulsion.com/product-page/navy-battery) is a High-performance Li-ion battery. The E80 Battery (https://www.epropulsion.com/product-page/e80-battery) is a 4096 Wh LiFePO4 battery. Different technology, but I don't know what the difference is.

I like the idea that the E80 has more Watt hours, and that it is more compact, but it is 36 lbs. heavier.

So what do y'all think so far?

I'd be looking at getting a sailboat.

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2 hours ago, Bull City said:

I like the idea that the E80 has more Watt hours, and that it is more compact, but it is 36 lbs. heavier.

So what do y'all think so far?

AIUI, LiFePO batteries are safer, and have a longer life but lower energy density: https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

Overall, I really like the sound of this idea.  The overall cost is modest compared to a new boat; more like the price of a new suit of sails.  And the installation should be fairly unintrusive.

If I read the specs right, the overall weight of the installation would be about 60kg for pod+battery, which isn't bad: that's about the weight of one slim crew member, but it will be low down. If you can charge it at your dock, it looks like a brilliant solution.

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10 minutes ago, weightless said:

E80

Navy

The E80 makes the most sense.

  • You save $1,200 between the battery and charger,
  • Longer life
  • Longer  warranty
  • You get 1000+ more Wh,
  • It's more compact, and
  • It's only another 36 lbs. of weight.

Am I missing anything?

My dilemma is where to put the thing. Under the cockpit makes the most sense, but I hate to give up my storage bin. I need to do some crawling around down there.

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2 hours ago, Bull City said:

Under the cockpit makes the most sense, but I hate to give up my storage bin. I need to do some crawling around down there.

2 hours ago, jdege said:

DIY batteries from bare cells are usually smaller than the commercial offerings.

Darn, didn't write down my notes for that compartment on account of tossing the idea for commercial battery packs. From memory there is virtually no space between the storage bin and the cockpit drains. Depends a bit on how exactly the drains are done in your boat.(ours are a bit forward so that there is space for the chargers aft of them)

Pulling out the drawer until it rests under the step nets you 170mm or so but comes with the downside of everything falling into the drawer now. Sacrificing a bit of drawer space with a custom one could accomodate a battery. Possibly, the E80 could be a real tight fit.

As jdege said, custom battery bank of the same size could be done to use space more efficiently. Know little about people with experience with actually doing it on a boat though. I know set ups exist and even get sold as designed kits to fit into specific boat compartments though. With the usual caveat of building a proper case where all the cells are secured to each other to avoid fatigue damage on the connectors. Otherwise it is not really more complicated than wiring a couple old lead acids together.(battery management included)

 

Anyway, if you can make yourself a custom storage bin(not as deep aft for example) the place would be most useful for weight placement and short, really short, cable runs.
Otherwise I know one H-boat sailor that mounted lead acid batteries in the lazarette forward of the rudder shaft. Bolted right to the wall to the cockpit. This would require somewhat longer cable runs but be entirely out of the way and weight wise not too bad.

Have you considered dropping the battery into one of the cockpit hatches? There is a suprising amount of space right under where the winches are. Quite a bit of mass to the side, but anchor on the other can reduce the effects of that potentially.

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17 minutes ago, allweather said:

Darn, didn't write down my notes for that compartment on account of tossing the idea for commercial battery packs. From memory there is virtually no space between the storage bin and the cockpit drains. Depends a bit on how exactly the drains are done in your boat.(ours are a bit forward so that there is space for the chargers aft of them)

Pulling out the drawer until it rests under the step nets you 170mm or so but comes with the downside of everything falling into the drawer now. Sacrificing a bit of drawer space with a custom one could accomodate a battery. Possibly, the E80 could be a real tight fit.

As jdege said, custom battery bank of the same size could be done to use space more efficiently. Know little about people with experience with actually doing it on a boat though. I know set ups exist and even get sold as designed kits to fit into specific boat compartments though. With the usual caveat of building a proper case where all the cells are secured to each other to avoid fatigue damage on the connectors. Otherwise it is not really more complicated than wiring a couple old lead acids together.(battery management included)

Anyway, if you can make yourself a custom storage bin(not as deep aft for example) the place would be most useful for weight placement and short, really short, cable runs.
Otherwise I know one H-boat sailor that mounted lead acid batteries in the lazarette forward of the rudder shaft. Bolted right to the wall to the cockpit. This would require somewhat longer cable runs but be entirely out of the way and weight wise not too bad.

Have you considered dropping the battery into one of the cockpit hatches? There is a surprising amount of space right under where the winches are. Quite a bit of mass to the side, but anchor on the other can reduce the effects of that potentially.

Allweather, Thanks for these ideas. The E80 battery weighs 106 lbs. (48 kg) so I have to give it some serious thought. I had not thought of the lazarette or cockpit lockers, since I felt it was important to keep the weight as low and centered as possible, and out of the ends of the boat.

I also have to figure out how to charge them while I'm away from the boat. I do not have a shore power system on the boat. There is a 110 volt outlet on the dock and I lead an outdoor extension cord safely to a point in the lazarette or cabin. 

I have some investigation and fact gathering to do.

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12 minutes ago, Bull City said:

 I do not have a shore power system on the boat.

You're welcome. I am not quite sure what you mean here? The standard charger for these batteries do come in 110V versions and from there it is just a simple cable run.

Weight wise you're right, the drawer below the cockpit is about as close as you can get to the CoB.(about below the companionway hatch... I mean where the lift ring is on the keel is about right :)

Going a bit further aft however is not that disastrous. From the back of the drawer to the lazaretty it is just about one meter. Cockpit locker literally just a wall. So some 30-40cm.
have fun locating everything onboard. ;)

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4 hours ago, weightless said:

Oh. For a 2kw charger?

I know very little about electricity. The charger designed to charge a 48 volt battery, and here is the description of the one I'm looking at:

Max output power: 1152 W
Max output voltage: 57.6 V
Output current: 20 A
Input voltage (AC): 185V - 255 V
Charging time: 9 hrs (E175 Battery), 5 hrs (E80 Battery), 2.5 hrs (E40 Battery)
Dimension: 235* 175 * 110mm

If "Input voltage" is the number to look at, it doesn't seem like a 110 volt outlet would work.

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8 minutes ago, Bull City said:

If "Input voltage" is the number to look at, it doesn't seem like a 110 volt outlet would work. 

Looks like they also have 110v models of both the 20A and 40A chargers. eg. 20A:

image.png.4d2068f3c7d6d578ce330b0ba91c13d1.png

I'm not going to opine on the extension cord idea except to say that I think getting expert advice before hooking things up would be a good idea.

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27 minutes ago, Bull City said:

I know very little about electricity

Same with many of us :) 

But given that lack of expertise, it seems that your options are 

  1. begin a crash course of earning a heck a of a lot about how this all works, until you enough expertise to design and build and test and safely install a self-designed system
  2. use the off-the-shelf setup designed and tested by the supplier, which they can stand over

I have a very talented friend who often takes the first approach with electrical projects, and usually ends up with something better than the off-the-shelf setup.  But the real gain for her is that she actively enjoys the project, since it allows her to use the electrical skillset that she last used professionally about 30 years ago.  So even if the DIY approach is abandoned, she is satisfied with the experience.

For me, I don't often get much of a kick out of such things, so I try to be an educated consumer.  I try to understand enough to asses whether off-the-shelf solutions are suitable, whether the price is sane, and if the supplier is reliable.  I don't try roll-yer-own unless there are significant savings, and the task isn't time-critical, and if I'd find it fun.  In the 1990s, I used to build my own desktop PCs, because it wasn't hard, the savings were significant, and the spec that I wanted wasn't available off the shelf.  But by the 2000s, I could buy a PC  for not much more than DIY costs which came close to what I wanted, so I gave up the DIY.

Sometimes I find a halfway house in the shape of a skilled friend who'd enjoy the project.  But that can lead to other tangles of expectations, so I am cautious.

In this case, it seems to me that DIY would be huge effort for small reward.

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8 hours ago, weightless said:

I'm not going to opine on the extension cord idea except to say that I think getting expert advice before hooking things up would be a good idea.

9 hours ago, Bull City said:

I know very little about electricity.

It should be straight forward enough. But with your level of skill in that regard getting a professional to do it for you is probably the better choice depending on what shore installation you have exactly...

You should not need more than a marine grade cable run to the boat/extension cord(won't degrade too much in the weather and has no issue with even being in the water. As seen in many a marina) DIY battery is out, but the E80 and the fitting 110V charger can be bought as is. Add in a switch, cables to the motor and charger that a professional can crimp in his shop once you determined lengths, and a fuse(nobody likes electrical cable fires) sized to those cables and you should be done.

Well, and checking the fuse between the outlet and the extension cord since I don't know about your shore installation. Both that there is one(likely) and that you don't accidentally blow it as your LiFePo can pull quite a bit of power.

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8 hours ago, weightless said:

Looks like they also have 110v models of both the 20A and 40A chargers. eg. 20A:

image.png.4d2068f3c7d6d578ce330b0ba91c13d1.png

I'm not going to opine on the extension cord idea except to say that I think getting expert advice before hooking things up would be a good idea.

Eureka! I did not see that. Thank you. Thinking about it, it would be foolish for them to not have a 110 volt charger.

As to shore power connection, the slips at my marina all have 110 volt receptacle, some have 30 Amp power, but they cost extra. My slip has only a 110 volt power receptacle. My concern was leaving an extension cord plugged in continuously. I found this "Weatherproof Receptacle Protector" cover which looks like it would do the job. 

It looks like the pieces are in place, now I have to look at space possibilities.

547139343_110vCover.thumb.png.135eb7315d1eb9edc0f9b4dd816137a1.png

 

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That is beyond my experience in regards to disturbed flow after the keel or in front of the rudder. My feeling would always value nice steering more but no idea...

Installation and access behind the keel is so much nicer however. From a rule of thumb approach I'd go with right in front of the frame below the winches.(number 3 "frame" at the keel) Not directly after the keel, still good access right besides the seacocks and you don't need to cut any large hatches for installation.

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My boat was designed to have two props, each driven by a 5HP gas engine. Someone replaced them with a single offset prop driven by a 27HP diesel.

I've been thinking about replacing that with a pair of 6HP electric pods, placing the props exactly where the original props were.

But then, my keel is rather unusual. The boat is almost a sharpie. It has a 4200 pound keel, but it's long and shallow. The boat only draws 20 inches with the boards up.

I'd think, with regard to positioning, that your want to position the pod so as to put the prop where the original prop was, if there was an original prop.

20200722_155252_copy_800x500.jpg

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1 hour ago, allweather said:

That is beyond my experience in regards to disturbed flow after the keel or in front of the rudder. My feeling would always value nice steering more but no idea...

Installation and access behind the keel is so much nicer however. From a rule of thumb approach I'd go with right in front of the frame below the winches.(number 3 "frame" at the keel) Not directly after the keel, still good access right besides the seacocks and you don't need to cut any large hatches for installation.

I also thought #3 looked about right - behind the keel and ahead of the winches.

18 minutes ago, jdege said:

I'd think, with regard to positioning, that your want to position the pod so as to put the prop where the original prop was, if there was an original prop.

Interesting boat you have. My boat, and H-Boats overall, were designed with no engine. OB power hangs off the transom.

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Here is a drawing showing the location. The blue rectangle would just contain the profile of the pod: 298 mm long, 350 mm deep. If the boat were ever lifted with a Travel Lift, it would be good to know that the pod was forward of the winches. 

1081587613_H-BoatPodPlan.thumb.png.f76cebb3487d49675518c187eb37a781.png

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32 minutes ago, Bull City said:

Here is a view of the J/100 showing the pod drive.

image.png.ed4235687738a068384e303a723e9a14.png

That's the exact same drawing that J boats uses - so that is the standard diesel with a saildrive, not a pod drive.

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42 minutes ago, slap said:

That's the exact same drawing that J boats uses - so that is the standard diesel with a saildrive, not a pod drive.

That's true, but my purpose was to show the fore & aft placement.

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Conventional wisdom says that a prop that far ahead of the rudder will hinder maneuverability due to limited prop wash over the rudder, but on boats this light and responsive I wouldn't worry about it. My boat is 34', 10000lbs, with a prop forward like that and it works just fine. So go ahead and put it wherever it fits best.

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10 hours ago, andykane said:

Conventional wisdom says that a prop that far ahead of the rudder will hinder maneuverability due to limited prop wash over the rudder, but on boats this light and responsive I wouldn't worry about it. My boat is 34', 10000lbs, with a prop forward like that and it works just fine. So go ahead and put it wherever it fits best.

With a spade, does it matter much?

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18 hours ago, andykane said:

Conventional wisdom says that a prop that far ahead of the rudder will hinder maneuverability due to limited prop wash over the rudder, but on boats this light and responsive I wouldn't worry about it. My boat is 34', 10000lbs, with a prop forward like that and it works just fine. So go ahead and put it wherever it fits best.

The H-boat's rudder is so far forward that it will be fine

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On 12/20/2020 at 9:07 AM, andykane said:

Conventional wisdom says that a prop that far ahead of the rudder will hinder maneuverability

True, but BC seems to be maneuvering the boat okay with an outboard. I don't expect the pod, even if it were to be tucked right behind the keel, would make maneuvering any more difficult.

In the interest of science, it might be enlightening to see how things work out with the pod placed forward of the keel ;)  I wonder if there'd be grant money for that?

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7 minutes ago, weightless said:

True, but BC seems to be maneuvering the boat okay with an outboard. I don't expect the pod, even if it were to be tucked right behind the keel, would make maneuvering any more difficult.

In the interest of science, it might be enlightening to see how things work out with the pod placed forward of the keel ;)  I wonder if there'd be grant money for that?

I guess you missed the latter half of that sentence where I said just that :p

 

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9 minutes ago, andykane said:

I guess you missed the latter half of that sentence where I said just that :p

 

Sorry about that, I was just using the quote to tee up a potentially amusing inanity. Were we not amused? Oh well, it's the thought that counts, right? ;)

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@andykane @weightless 

My maneuvering difficulty is because the OB is so far astern of the rudder. The OB is locked so that it doesn't pivot, and I steer with the tiller. The motor always wants to go straight. It's OK for gradual turns, but not in a tight turn, and it's worse when backing. I think the pod set up will be a vast improvement.

Forward of the keel? That would be strange. No control at all is my guess.

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33 minutes ago, Bull City said:

Forward of the keel? That would be strange. No control at all is my guess.

There might be a wee bit of control, but not much unless you install a swivelling pod.  Which might be just a wee bit excessive for a wee boat.

In of the Sailing Uma episodes after they switched from their home-made "ElectroBeke" to an OceanVolt saildrive, there was some interesting footage of how they had to readjust their docking technique.  The Electrobeke had a very direct throttle response, so they could switch rapidly between fwd and reverse, with no risk of damage because the chnange was wholly electrical.  But the OceanVolt controller is configured to mimic a diesel engine with a gearbox, where the need to a dear gearchange without crunching cogs means that there is a bit of a lag between propelling the boat in one direction and giving a corrective burst in the other direction.  They had to retain themselves to deal with the OceanVolt's laggy response.

I dunno how the E-Propulsion's controller is set up, but it would be nice if such controllers had two modes: a fast-response "native electric" mode, and a laggy "like a diesel" mode for those used to the dinsoaur squeezings.

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@weightless I have seen some newer boat designs where the pod is mounted on the trailing edge of the fin keel, or on the trailing edge of the rudder.

When I trained to be a naval officer (in the 1960s), we studied the interplay between propellers and rudders in a naval engineering class. It made my head hurt.

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1 hour ago, TwoLegged said:

I dunno how the E-Propulsion's controller is set up, but it would be nice if such controllers had two modes: a fast-response "native electric" mode, and a laggy "like a diesel" mode for those used to the dinsoaur squeezings.

The Torqeedo OB has a little bit of delay when moving from neutral to either forward or reverse. No delay when accelerating or slowing. I imagine the pods are similar.

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14 minutes ago, Bull City said:

When I trained to be a naval officer (in the 1960s), we studied the interplay between propellers and rudders in a naval engineering class. It made my head hurt.

Indeed. I've hidden the my post on that 'cause I committed multiple stupidities in it. I do suspect that putting the pod near the trailing edge would give it less moment to steer the boat with prop-wash and would put it's drag further from the pivot point of the boat. Those might give the rudder a better chance of controlling the boat in reverse.

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7 minutes ago, Bull City said:

little bit of delay when moving from neutral to either forward or reverse.

Electronically controlled throttles for diesels sometimes add delay in, too. I suspect that's intended to protect the gearing and shafts. It may be a useful thing even on an all electric setup. Sheering the prop off the shaft would not be helpful.

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@Beanie 101  @DDW  @ChrisJD  I'm getting pretty far along with the ePropulsion Pod Drive 3.0. The company rates it at 6 HP, which would be an improvement over the Torqeedo 1003, which I now use. As has been discussed on other threads, Torqeedo probably over rates the HP. The 1003 at wide open moved my boat at about the same speed as my old Honda 2 HP, also wide open. 

So, my question is how accurate do you think ePropulsion is at rating the HP of their products? Is 6 HP really 6 HP?

Thanks.

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On 12/21/2020 at 1:40 PM, weightless said:

Indeed. I've hidden the my post on that 'cause I committed multiple stupidities in it. I do suspect that putting the pod near the trailing edge would give it less moment to steer the boat with prop-wash and would put it's drag further from the pivot point of the boat. Those might give the rudder a better chance of controlling the boat in reverse.

Here's the J/109 saildrive location.  I'd guess the distance to the rudder from the saildrive is almost the same as it is on the J/100.  The J/109 is one of the easiest boats to drive and maneuver around the docks, forward or reverse.  There is plenty of flow from the prop over the engine in forward to kick the stern one way of the other if needed.  There is very little prop walk in reverse.  Several times while backing down a narrow fairway into my slip, I had other "dock watchers" tell me it must be nice to have a bow thruster...

I think Bull will be shocked at how easy his boat becomes to drive and maneuver should he put a pod drive (or saildrive) in the location he is showing.

J/109 Standard (J/Boats) - Sailboat specifications - Boat-Specs.com

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At 3kW it's actually only 4hp, although I would expect it to have much better performance in reverse since you don't have exhaust gas getting sucked into the prop. I guess running this at 100% is comparable to running a 6hp gas outboard at "cruising rpm"?

For comparison the Torqeedo 1003 appears to be 1.1kW, so the pod is certainly a decent step up.

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Yeah, input power is 3000 watts and as a matter of settled physics that is at most 4 hp, electric motors are ~90% efficient so less than that output. A 6 hp outboard probably doesn't produce 6 hp at the prop though. If a boat is getting pushed at close to hull speed, then the difference is small. I didn't think gas outboards had a "cruising rpm", you just run them wide open all the time. A somewhat esoteric real world example, I've had the eProp Spirit and a British Seagull Silver Century on my (rather heavy) Bullfrog dinghy. 1KW vs. 5 hp claimed. It goes maybe 0.3 knots faster with the BS engine. You are used to the Torqeedo, and it is probably very real that this will be 3 times as powerful. 

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24 minutes ago, DDW said:

A 6 hp outboard probably doesn't produce 6 hp at the prop though

Aren't outboards usually rated at the prop?

I wonder what "maximum overall efficiency 51%" means in the specs? Maybe the input charge -> motor output?

IIRC, the 1003 is rated 800 ish watts at the prop.

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8 minutes ago, weightless said:

Aren't outboards usually rated at the prop?

I wonder what "maximum overall efficiency 51%" means in the specs? Maybe the input charge -> motor output?

IIRC, the 1003 is rated 800 ish watts at the prop.

An “at the prop” rating must be shaft hp at the prop. Prop losses not included. Easy to measure with a dynomometer.

A “max overall” spec of a system that includes a prop implies they are measuring thrust at some particular speed. Hard to measure. Sounds dubious.

A 51% efficiency is reasonable for control losses, wiring, motor at max power, bearings, cooling losses, etc. DC motor efficiency is only high (80-90%) at relatively low speeds and low power, quickly deteriorating (to 50%) as speed and power increase.

It is what it is...good or great if the goofy thing satisfies ones needs.

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I tried to compare the HP, Watt, and thrust Tech Specs for the Torqeedo Travel 1003, since I have one, with the ePropulsion 3.0 Pod (6 HP) and the Torqeedo Cruise 2.0 Pod (5 HP). Of course they use different measures/terms. Here's what I came up with. I would be grateful for your observations.

                                                                                                 Torq 1003    eProp 3.0    Torq Cruise 2.0    
Input power in watts                                                             1000             3000            2000
Propulsive power in watts                                                    480                ?                  1120
Comparable petrol outboards (propulsive power)            3 HP             6 HP            5 HP
Comparable petrol outboards (thrust)                                4 HP             ?                   6 HP
Maximum overall efficiency in %                                          48                 51                 56
Static thrust in lbs*                                                                 68                 ?                    115

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17 minutes ago, Bull City said:

I tried to compare the HP, Watt, and thrust Tech Specs for the Torqeedo Travel 1003, since I have one, with the ePropulsion 3.0 Pod (6 HP) and the Torqeedo Cruise 2.0 Pod (5 HP). Of course they use different measures/terms. Here's what I came up with. I would be grateful for your observations.

Each of the possible new engines delivers at least twice as much power as the current outboard.  So why does the compariosson matter?

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I guess you can fill in the eProp's "propulsive" power as 3,000 x 0.51 = 1,530. There are about 746 watts in a hp ("in 1492 Columbus sailed the ocean blue and if you divide that number in two...").

I'm very skeptical of the "comparable" with outboards of some power numbers. And I'm not sure what they mean by "propulsive power". I think they don't mean power at the prop shaft and suspect they're including the complications of propeller choices. That seems not helpful and potentially misleading to me.

The top line for the electric looks like apples to apples. WAG: all else being equal, the eProp should deliver around three times the power of the 1003. All the numbers below the top line seem a bit fishy to me.

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I did some crawling around with a tape measure today. There is really only one place for the E80 Battery and pod drive, and it's probably the best place: under the forward end of the cockpit. In the plan below, the pod is still in blue, and the battery is in red. It will mean loosing the storage bin, but there's just a few lines in there. The place where I keep the spare Torqeedo batteries will be freed up, and that will easily house the lines.

40812149_H-BoatPodPlan1.thumb.png.e61cff7bb19a988d278898fbd83d5a2f.png

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Just wondering:

Can you get a folding or feathering prop? What are the options for prop selection and sizing?

Will it harm anything in the system to let the prop freewheel? 

Can the prop be locked?

Is there someone with one of these installed on a sailboat who can share their experiences? 

Has anyone ever kept one of these in the water full time? What about anti-fouling?

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13 minutes ago, weightless said:

Just wondering:

Can you get a folding or feathering prop? What are the options for prop selection and sizing? ePropulsion does not offer one, but Torqeedo does, for $900. Also, another company, Aquamot, makes a pod, They offer a folding prop too. I've requested pricing from them. 

Will it harm anything in the system to let the prop freewheel? I am guessing not, otherwise, they would have a locking mechanism. 40+ years ago, I raced with a friend on a Tartan 27. He had a 2-bladed prop, and would go below and line it up with the keel to reduce drag.

Can the prop be locked? Don't know, but will ask.

Is there someone with one of these installed on a sailboat who can share their experiences? I've corresponded with a fellow in Switzerland who has an Aquamot on an H-Boat. He's had it for 3 years and is happy. It replaced a Yanmar, when the lake banned 2-cycle engines.

Has anyone ever kept one of these in the water full time? What about anti-fouling? I asked the fellow in Switzerland, but haven't heard back. He hauls at the end of summer.

These are excellent questions. Answers above.

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24 minutes ago, TwoLegged said:

Why you want to lock the prop? Even if you aren't using regen, surely locking it just increases drag?

If it's 2-bladed, and you could lock it so it's vertical and parallel to the keel, it might be good for drag.

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7 minutes ago, Bull City said:

If it's 2-bladed, and you could lock it so it's vertical and parallel to the keel, it might be good for drag.

I'm no expert, but I would have thought that free-spinning would be less drag than locked in any position.  It's going to be about 2feet behind a foil, in fast-flowing water, not tucked into a fat cutout on a long keel.

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47 minutes ago, TwoLegged said:

I'm no expert, but I would have thought that free-spinning would be less drag than locked in any position.  It's going to be about 2feet behind a foil, in fast-flowing water, not tucked into a fat cutout on a long keel.

Marginally less drag, and a lot of wear on the components. I'd go fixed vertical.

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1 hour ago, TwoLegged said:

Why you want to lock the prop? Even if you aren't using regen, surely locking it just increases drag?

I was wondering if letting it freewheel might cause harm -- stresses diodes, burns bearings, wears seals, makes a horrible racket,  to force a folding prop to fold, whatever. If so, then locking it might be a useful thing. Drag may not be the only consideration.

The drag argument can take over a conversation. My guess, similar to yours, I think, is locked would be more drag. Still, locking the blades, particularly if you could keep them in the wake of the keel, might be desirable all things considered.

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Aquamot also makes an electric pod drive, which I'm looking into. Their website says this about placement of the pod:

Where and how should fixed pod motors be mounted?
Generally fixed pod motors are mounted between keel and rudder. Moreover, it is better that the motor is place closer to the keel than at the ruder. After the propeller there are hydrodynamics turbulences and therefore vibrations at the ruder can be the consequences. Furthermore, the motor is also positioned at the lee side from the keel and the motor has a lesser resistance. The fixed pod motors should be mounted parallel to the waterline for having the max. thrust. This is why Aquamot supply custom-made compensation wedges which are also vibration-dumping.

I think they're saying that because of turbulence aft of the keel, there's not as much drag.

WIE SIND FLANSCHMOTOREN ZU PLATZIEREN?
Grundsätzlich werden Flanschmotoren zwischen Kiel und Ruder positioniert. Dabei soll der Motor näher beim Kiel als beim Ruder sein. Der Grund hierfür ist, dass nach dem Propeller Verwirbelungen entstehen und somit Vibrationen am Ruder hervorgerufen werden können. Desweiteren ist der Motor auch im Lee-Wasser vom Kiel und hat somit einen geringeren Schleppwiderstand. Außerdem sollen Flanschmotoren parallel zur Wasserlinie angeordnet sein. Dafür werden von Aquamot maßgefertigte Ausgleichskeile angeboten, welche zugleich schwingungs- und vibrationsdämpfend sind.

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1 hour ago, weightless said:

I was wondering if letting it freewheel might cause harm -- stresses diodes, burns bearings, wears seals, makes a horrible racket,  to force a folding prop to fold, whatever. If so, then locking it might be a useful thing. Drag may not be the only consideration.

The drag argument can take over a conversation. My guess, similar to yours, I think, is locked would be more drag. Still, locking the blades, particularly if you could keep them in the wake of the keel, might be desirable all things considered.

It’s a bit of a complicated argument.  With a bunch of “it depends”

on airplanes, a windmilling prop, whether 2 or 3 blades, almost always has more drag than a stopped prop.  But airplanes don’t all have transmissions with a “neutral” to disengage the engine.  Also airplane prop blades are long and thin.  Sailboat props, esp 3 bladers, are short and fat.  Plus sailboats have transmissions to decouple the engine.  
 

My gut says if you have a fixed 2 blade prop, locked, inline with keel is less drag than rotating.  But a locked 3 blade probably has more drag vs a rotating prop.  
 

Note: transmission wear and cutlass bearing wear not considered....

Electric motors complicate the equation as there may not be a transmission neutral position, and regen is possible...

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Yachting World did drag testing on locked and freewheeling props. The result was mixed, depended somewhat on the drag on the shaft, size and number of blades, etc., but overall conclusion was freewheeling was less drag most of the time. 

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I noticed a few things about the ePropulsion 3.0 pod compared to the Torqeedo 1003 OB. 

I understand that the Torqeedo has a reduction gear and that the eProp does not. The Torqeedo technical info says the maximum propeller speed is 1200 rpm, the eProp says 2300 rpm.

The two drives are similar in size, but the propellers are different looking. The eProp propeller has a smaller diameter (10.24" v 11.5") but the pitch  looks more aggressive. Combined with a higher rpm, I guess it means more power.

597222583_eProp3.0vTorq1003profile.thumb.png.ff3464e623d8bfc89eea1a6941db0338.png

 

945395152_eProp3.0vTorq1003end.thumb.png.c641ceb852703545c1833ce826a9118a.png

 

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I've been thinking about installing the pod system. This is a photo of the space shown in Post #72. Usually there is a storage bin here that slides in and out. The space is about 29" deep, and the thru-hulls (for the cockpit drains) take up the last 6" from the aft bulkhead. There is plenty of room for the battery. The space directly astern is not accessible. 

The pod drive would be installed on the centerline. As you can see, there is a drainage hole at the bottom of the bulkhead, and there is drainage that runs forward to the bilge, so that will have to be allowed for. I'm not sure how to do that.

UNADJUSTEDNONRAW_thumb_57ae.thumb.jpg.0f3e872008cbb757d96152cb354c4524.jpg

My preference would be to mount the battery (in blue) close to the forward end of the space, so that the various controls and indicators are accessible. In that case, the pod (in red) would be mounted toward the rear of the space. On the other hand, it might be better to mount the pod closer to the keel, and battery behind it, which would be OK. Either way, I would need to fabricate some "floors" with a space for drainage to support the battery. 

I'd be interested in comments and suggestions.

Installation.thumb.png.6a8196a8db1f9c33f51346ba464548fe.png

 

 

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Whatever you do, replace those two gate valves while you can still access them!! Can you post drawings of drive inside the hull? You have two choices on drainage: totally ignore it, accept that you might have to sponge out behind motor as needed, or create a ditch around motor head, & fill in v-groove to eliminate standing water. Either way, you want to have powerhead on an "island" so that it keeps motor dry at (almost) all times.

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