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RonW
03-19-2005, 06:55 PM
I have very easily talked glen-l into adding a section to their message board on electric propulsion. Feel free to browse or add to this subject.

http://www.glen-l.com/phpBB2/

Today gas hit $2.19 in cincy, and from what I hear it will be from $3. to $4. by 2010 all across the U.S. just like europe.
Honda and toyota are selling their hybrid vehicles left and right, ford is suppose to have 3 models by 2006, lexus now has a hybrid.

If you would like to see some real pretty electric boats. Also scroll down to the bottom of the home page and click on to the short movie, pretty neat.
http://www.electriclaunch.com/index.html

AngWood
03-19-2005, 09:47 PM
Way to go!

The forum at www.eboat.org (http://www.eboat.org) stopped working weeks ago. I'm building a 15ft skiff that I'll power with a trolling motor and (I hope) two deep-cycle batteries. I'll fo' sho' need some help with wiring and such in a month or two.

RonW
03-19-2005, 10:05 PM
AngWood, under the glen-l electric heading, click onto the post I put up about links, at the bottom is a link to a page about deep cycle batteries for e.v.'s You will learn more about a battery then you thought was possible.
If you need 24 volt, you want to look at the trojan -5shp-

You may also be interested in this. A trolling motor where you take the control head off and move it to another location in the boat, instead of having to sit next to the transom.

http://www.glen-l.com/designs/special/etm.html

Lynn A Miller
03-22-2005, 02:26 PM
For some time now I have been investigating using the recently invented Cedric Lynch permanent magnet motor for auxillary propullsion on a moderate size sailboat. The motor produces 72rpm per volt from 12-48volts, and is rated at 8-10 hp, and when it is being turned by the prop as you are sailing it recharges the batteries, which I was going to place along side the centerboard trunk for ballast. It weights about 22 lbs, and is only 7" in diameter. It was going to be made by Briggs and Stratton under the name ETEK, and attached to an outboard lower unit, but I have recently from them that they are just going to buy a 3hp design from a Chinese manufacturer instead.

I was going to mount the motor on top of a 15hp outboard lower unit (see the Glen-L design for details) and mount that just aft of my centerboard slot in a well that would allow me to raise it out of the water while sailing or when in very shallow water. But since B&G has opted out, and since I cannot afford the systems that Solomon Technologies sells (see the latest issue of Cruising World), its back to the drawing board.

The Thames Elecric Boat Co website shows a simpler solution, a "sail drive" with the motor in the submerged unit, but I don't have any details on it, and I can't seem to get the company to respond to my e-mails. Is anyone selling their sail-drive units here in the States, and has anyone had any experience with them (do they act as generators when sailing, do they come with controllers, etc)?

Dave Lesser
03-22-2005, 10:21 PM
The Europeans seem to be ahead of the US in the development of diesel-electric hybrid propusion for marine applications. There is a lot of information on this Fischer Panda (http://www.fischerpanda.de/w09_product_eng_154_product.html) website about their range of products. Note that this appears on the German Fischer Panda site (English translation), not on the American site.

This link is to a .pdf brochure that covers their products, including a rotating, retractable saildrive:

http://domino.fischerpanda.de/public/FPProspe.nsf/PDFPreview/BF6A1CDB8C40F43000256CC20045430D/$File/wh2002eng_v05.pdf

The following link shows the installation in a Bavaria 49. For some reason, I can't get the whole URL included in the link - note that you have to add "DE_eng.pdf" at the end of the link.

http://domino.fischerpanda.de/public/FPProspe.nsf/PDFPreview/B77EC347356AC336C1256F3100446CD7/$File/Bavaria49Whisperprop DE_eng.pdf

These systems can also apparently re-generate electricity while moving under sail. I don't know if they are marketing them in the US, nor how their prices compare with Solomon Technologies.

skuthorp
03-23-2005, 12:05 AM
At Goolwa there was an electric paddlewheeler with feathering paddles and very classy cane chairs.
http://community.webshots.com/album/295083598zPosUm/0
pic0021
Fast too :D

Tom Lathrop
03-23-2005, 07:16 AM
Scuthorp,

Great pictures of some really nice boats. Not sure I'd want to be on the riverboat in #90 when everyone ran to one side to see something though. Looks like the weather could have been better.

Dave Lesser
03-26-2005, 12:16 PM
I spoke briefly with Dave Corcoran at Bullhouse Boatworks (http://bullhouseboatworks.com) about the electric motor installation in his new Fish Class. He sounded very satisfied with the performance of the system and the technical support that he had received from Elco (http://www.electriclaunch.com/)

RonW
03-26-2005, 02:58 PM
There are at least 4 sources that will sell you a complete system and tell you how to set it up.
Besides elco which is excellent, there is also

Beckman out of rhode island.
http://www.steamboating.net/page40.html

And there is Bob Batson from e.v.america
http://www.ev-america.com/index.html

Sailboaters might be interested to know that solomon has a system that actually recharges itself while under sail, no need to ever plug into shore power.
http://www.solomontechnologies.com/Solomon%20new/index.html

Dave Lesser
03-26-2005, 03:27 PM
The Air Cooled Gas Inboard (http://www.woodenboat-ubb.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=011237) thread refers to some Hatz diesels sold by Northern Tool and Equipment. I searched the Hatz website and found these Air Cooled Diesel Gensets (http://www.hatz-diesel.de/englisch/produkt/stromaggregat_e.htm). Does anyone have any experience with air-cooled diesel gensets? How noisy are they? Can they be shielded or encapsulated using a fan to provide cooling air flow? It seems like they could be a good component of a diesel-electric hybrid propulsion system. The only through-hull needed would be for the propellor shaft.

Dave Lesser
04-04-2005, 10:44 PM
I just received a copy of Professional Boatbuilder (http://www.woodenboatstore.com/prodinfo.asp?number=199-092), issue #92, Dec 04 - Jan 05. It contains a fairly extensive article by Nigel Calder about the current state of the art for diesel-electric propulsion systems. He mentions the Fischer Panda, Glacier Bay and Solomon Technologies products, but for some reason did not include the systems from Elco. Definitely worth a look.

RonW
04-06-2005, 06:51 AM
http://www.electriclaunch.com/hybrid.htm

Dave here is elco's diesel generator, they say 66 db. at 3 ft. away for noise level. In rereading the specs on this genset, it looks interesting to say the least. Water cooled, quiet, only uses 2/10 of a gallon a hour, they say it will run for 75 hours on 15 gallons. It also puts out 4.4kw that is enough to run a 6 horse motor on high, and a 6 horse elect. motor is equivalent to a 21 or more horse gas or diesel.

I see where you are coming from now. Just have a small battery pack to make up the voltage required, run off the batteries when just putting around and when underway turn on the generator. With 75 hours plus and a 6 horse electric motor, it would make a prettty nice system.

If you figure out more on this, let me know, it is beginning to sound very interesting.

RonW
04-06-2005, 08:04 AM
Yea that is budsin out of north carolina, just up or down the road from you. His 22 footer, the picture in the middle is pretty nice. I think the electric boat may be getting ready to come into the picture big time in the next 5 years.Look at my original post, march 19 and gas hit $2.19, well yesterday april 5 and gas was $2.34. I think they are breaking us in for the $3. a gallon deal.

These hybrid systems can run some very large boats.Like I said elsewhere there is a german website and they have a very nice 21 footer that they use to water ski with. It runs 18 m.p.h. and I am sure they use wide water skis, but hey it is all electric.

RonW
04-06-2005, 08:17 AM
http://groups.yahoo.com/group/ETList/

Here is a very interesting site that I have been reading this winter out of boredom. I am defintely not a left wing, tree hugging, vegetarian and let's save the one eyed pink spotted salamander. But this site has some interesting stuff to say the least. A lot of articles on hybrid vehicles, new battery technology and some interesting stuff on watering down gas and diesel fuel with some kind of processed vegetable oil. Something like watering it down up to 90%. Go back and research the archives, electric boats may be coming sooner then we think.

RonW
04-06-2005, 05:51 PM
Great pictures Mike, the main reason to own a electric boat.The bottom picture looks like a great place to fish.

joejapan
04-06-2005, 08:03 PM
Mike, speckled trout are also called spotted weakfish and, sometimes, sand trout, depending on the location. They are, all three, the same species and are commonly found in the Atlantic, N.Caribbean and Gulf of Mexico. Spring temperatures cause them to migrate toward shorelines and summer temperatures drive them a bit deeper, only to return to the mouths of rivers and estuaries in the early fall. They are great sportfish, great eating, and both of your photos look like prime fishing spots.

Sure wish the hell I could catch a good "mess" of them over here.

Edited to add apology : Oops, sorry, didn't mean to get away from electric boats !

[ 04-06-2005, 09:07 PM: Message edited by: joejapan ]

RonW
04-06-2005, 08:14 PM
Speckled trout, tell me about these. I am not from cincy but w.va. and grew up in national forest fishing for brook trout and rainbows. I see where along the coast of carolina's and florida and over to texas they have salt water trout, how do these compare in eating and catching to the freshwater variety? That sounds like a blast particularly with light spinning or fly rod from a electric boat.

Looks like I took to long to type, thanks..

[ 04-06-2005, 09:16 PM: Message edited by: RonW ]

Donn
04-06-2005, 08:24 PM
RonW...it's the Spotted Seatrout, known as Weakfish up here. It has absolutely no relationship to freshwater or anadramous trout. It's a fine-fleshed, dry fish, without the oil that characterizes real trout. It takes artificials readily, from plugs to grubs, and eats very well.

RonW
04-09-2005, 11:11 PM
Dave lesser- check out these quiet honda generators, they are every bit as quiet. The largest one goes up to 5500 watts. they do run on gas rather then diesel. All you would have to do is plug your charger into the generator just the same as a regular socket, and you have a hybrid system. They are readily available and probably a whole lot cheaper too.

http://www.hondapowerequipment.com/gensup.asp

Been thinking about this since you brought it up.

Dave Lesser
04-11-2005, 06:10 PM
RonW,

I worry about gasoline on board, especially with all of that electricity floating around. An air-cooled diesel genset would be safer, but probably has more noise. There is some good info on the Air Cooled Diesel (http://www.woodenboat-ubb.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=011237) thread in Building/Repair. It sounds like they generate too much heat to be kept below decks without hefty cooling fans. I wonder if they could be kept on deck in some kind of louvered enclosure

RonW
04-11-2005, 10:44 PM
Dave- we have moved the conversation into the hybrid electric boat. What are you contemplating?
How long and what is the weight of your boat?
How much voltage and what horse electric motor as well as how many amp hours on the batteries do you plan on having? So just how much generating power do you feel that you need?
Most of the german gemerators you posted run off of a liquid cooling system and the big 5000 watt honda does too.
If the generator isn't very quiet, I kinda think it defeats the whole purpose.

Dave Lesser
04-13-2005, 07:52 PM
I’m thinking (in the abstract) of a cruising boat in the 20,000 pound, 35 foot range. This would require an electric motor in the 6-8 hp range. The Solomon ST-37 has 6 hp and 37 ft-lbs of torque, requires 144 volts DC. Elco has motors in the 6-10 hp range that use lower voltages.

I would want 3-4 hours of battery storage. This would suffice for getting in and out of marinas, and provide some backup if the wind died while day-sailing. Fewer batteries would mean less weight, space, and cost – figuring a 5 year battery life. More batteries would lengthen the time between charges.

The question then becomes how to recharge the batteries. Can be done overnight if staying at a slip with shore power. Solar and wind generators probably not much more than trickle charges. That leaves a genset as best option for extended cruising. Even though there is power loss from the genset to the batteries to the electric motor, fuel economy may beat a standard diesel auxiliary because the genset can be tuned to operate at a single RPM. The genset can be encapsulated for noise abatement. An air-cooled genset would avoid the need for thru-hulls but would be noisier, and one would have to deal with the exhaust.

Solomon touts regeneration by turning the prop while sailing, but it probably takes 3-4 hours of sailing at hull speed to generate one hour of battery power. The people at Elco told me that they don’t think regeneration really works as advertised. At any rate you have to be willing to put up with considerable drag from a large prop.

I spoke with the Hinckley rep who was showing their 42 ft daysailer at the Annapolis boat show last fall. It has a 14,000 lb displacement and a slippery hull shape. It had a 6kw AC generator and a Solomon ST-37 motor. They were unable to run at hull speed indefinitely with that combination because of power loss in the AC to DC conversion, but the owner wanted AC power on board. They’re looking at DC generators in future installations.

There is a company in California that is looking at fuel cells to repower the batteries, but I would not be very enthusiastic about hydrogen on board. Also prohibitively expensive. All of this seems to fall in the “not quite ready for prime time” category, but at least things seem to be evolving. It would be nice if one of the Toyota Prius engineers was also a sailor.

RonW
04-13-2005, 11:04 PM
Dave- It sounds like you have been doing a lot of figuring. I take it for granted that this is a sailboat.I agree with the smaller voltage.
Here is some of my thoughts and opinions for what they are worth.

The speed dissplacement chart shows 500 lbs for each horse at 1.34, at a 30 foot waterline that would equate to 7.3 knots and equate to a 40 horse gas or diesel engine. You figure about
3& 1/2 electric horse for every internal combustion engine horse, so that would be about 12 horse electric. But just to move around the harbor, 1.1 equates to 6 knots and 22 horse diesel or 6 horse electric. You could easily do a 48 volt system, and I would see no need for more then 72 volts. You also want to look at the continuos run time on the motor.

I think you only need a small generator, about 3 or 4,000 watt maximum. I do not see a big loss in converting the energy, most good chargers are 85 to 90% efficent. But they are limited to their ability to charge, and besides that you can only recharge a battery so quick. You can not just zap them with a heavy charge. If the charger will only put 2400 watts in to the batteries, there is no need in producing more then 2800 watts, it can not be used and you are just wasting fuel in producing it. I think that is what they are doing with the 6,000 watt generator.
http://www.zivanusa.com/NG3BatteryCharger.htm

Those german diesel generators are very fuel efficent and quiet, so is the small hondas, but you have gas. Where to put it for exhaust is another problem. I would think a boat that size finding room for 50 gallons of diesel would be no problem, even if you pumped it out into a seperate container manually.I think you might have enough fuel to recharge those batteries 8 or 10 times, without researching the fuel charts.

On batteries, a 6 horse 48 volt motor would be
6 x 746 watts for one electric horse, which =
4,476 watts divided by 48 volts = 93 amps draw.
To disscharge the batteries at a greater then 10% disscharge rate means that you can only expect a 50% disscharge wattage. Which means 4 hours x 93amps = 372 amp hours. You now have to double that to 744 amp hours to account for only a 50% disscharge rate. If you look at the trojan 5shp a 12 volt 165 amp hour battery with a 560 disscharge and recharge rate, that means you need 20 batteries at 87 lbs a piece, which is 825 amp hours. If you reduce it to 16 batteries that would give you 660 amp hours and about 3+ hours of running time. But remeber this is on high and all of the 6 horse, you can just use a littel less power like around the docks at 2 or 3 horse which would probably still be 3 to 5 m.p.h. and double that time frame.

You can also run the generator at the same time you are driving around.This changes the whole equasion.

I think it is a very simple and easy to do system, and can be done at a very reasonable rate.
Probably around 4 to $5,000. on the electrical and batteries, and 3 or $4,000. on a german generator.

You need to get hold of bob at www.evamerica.com (http://www.evamerica.com)

And that is my .02 cents worth, hope this helps.

Dave Lesser
04-14-2005, 09:18 PM
Ron,

Sounds like you have done a lot of figuring, too. I appreciate your analysis. I seems like every supplier has lots of charts and specifications, but I wonder how the theory transfers to practice. It sure would be nice if there were a few more "test platforms" for cruising boats using these systems, with reports from the field about their strengths and weaknesses. There is a huge difference in price between a Solomon and an Elco system, and I'm not sure that I understand why. Also, there are new systems in R&D and just coming to market. Nigel Calder has been impressed with the Glacier Bay equipment. I bet that in 5 more years, the technology will be much more mature, and the choices will be clearer. I'll post any additional information that I discover.

RonW
04-15-2005, 12:56 AM
Yes I have been doing a unbelievable amount of research into electric boats. And within the next month I am starting on a 26ft. by 7ft-3in. all electric with enough juice and horsepower to spend the weekend on it, not just driving around in circles on the pond for a couple of hours.

I don't think the next few years will bring much new things, think we all ready have them. There will be mass improvements in batteries though, and when they double and triple the batteries amp hours, the electric boat will come alive.
The germans already have a 20 footer, all electric that they use to water ski with.
In 1900 there where more electric cars then there where gas cars. Believe that or not. And chuck who owns elco still owns a share of his great grand fathers electric boat that was bought at the 1893 world trades fair in chicago. It still has the original electric motor in it.
Electric is old technology, not new, we just improved the circutry.

I do know that some of these builders are putting things together wrong. Think solomon needs to do a lot more research into battery technology.This is strange till you understand it.
Do think some of the builders are going to have to work on things like props, gear ratios, battery banks and voltage as well as trying to put hybrid systems together. Like I said above, why worry about your generator if the battery charger won't even handle it. Zivan does have chargers that will put charge up to 10,000 watts, but they also require 400 volts in, too much juice for me.

Elco, Beckman, and duffy all have straight forward systems that work just fine and are put into sailboats as auxillaries.
Here read this on batteries, hard core stuff.
http://members.aol.com/brucedp/evbatt.txt

The bechman site I posted above shows a system by evamerica with price.
What is this glacier bay and new systems in R&D.
Do you have any links to sites concerning this?

Dave Lesser
04-16-2005, 09:37 AM
Here's the website for Glacier Bay. (http://www.glacierbay.com) They have been making marine refrigeration equipment for a long time. Look at the OSSA Powerlite systems under the Products tab. The information on the web site is fairly limited, but they have more extensive printed literature. I'll be visiting their facility this summer to get more information

Stiletto
04-16-2005, 05:46 PM
Donn, do you have a picture of the speckled trout?
I want to see if we have anything similar over here.

Donn
04-16-2005, 06:12 PM
Google "Cynoscion nebulosus"

It's most common common name is Spotted Seatrout. The version I catch is Cynoscion regalis, or Weakfish, so-named because of the delicate tissue around the mouth.

This is a Spotted Seatrout:

http://www.landbigfish.com/images/fish/spotseatrout.jpg

This is a Weakfish:

http://www.dimitry.com/trophyprints/images/weak2sm.jpg

I'm pretty sure you have C. nebulosa, or a close relative, down there. It'd be interesting to hear what you call it.

imported_Dutch
04-17-2005, 07:15 PM
here is bolgers lily

http://www.adirondackgoodboat.com/images/lily.jpg

landlocked sailor
04-17-2005, 07:36 PM
And here too, Rick
http://www.imagestation.com/picture/sraid134/pc97cbb52914bd1bab6a14d401345f853/f77abfcc.jpg

Stiletto
04-18-2005, 04:09 AM
Thanks Donn,

The nearest to it that we have is called a Kahawai, Arripis trutta. So it is not related. www.fishnz.co.nz/species.cfm?cat=Saltwater

Which I have just found out are called Australian salmon according to a quick google search.

I caught one on Friday a bit over half a metre long. They are quite a good fighting fish for their size.

My little fishing book I use to identify commonly caught species doesnt have any Cynoscion of any type listed at all. I cant think of any fish that I catch that arent in it .

[ 04-18-2005, 05:11 AM: Message edited by: Stiletto ]

werner
04-18-2005, 03:43 PM
electrical boats from 125 years ago seems they were not to happy about the batteries and range ?
http://www.imagestation.com/picture/sraid165/p3ef65faca0c70d11f5e3463b51f39cb3/f46c2daf.jpg.thumb.jpg

werner
04-18-2005, 03:57 PM
this should be better
http://www.imagestation.com/picture/sraid165/p85aad9a3a95c4fad6e66ebd45f78124e/f46c2da3.jpg http://www.imagestation.com/picture/sraid165/p3ef65faca0c70d11f5e3463b51f39cb3/f46c2daf.jpg

Dan Hobson
08-16-2005, 12:58 AM
This is a great resource thread. I want to compliment every person who posted here. And add a thought or two. I've been playing around with a small electric boat for some time now. It's a twelve foot cat boat hull (beamy) that I added an electric auxiliary to. I had to take apart a minnkotta 2hp and build it into the rudder. It uses two deep cycle batteries because I like the ballance and the range I get from two batteries on board. And there's a small coleman generator as well to give the possibility of recharging away from a dock.

So what's it all for?? Why electric??

Electric boats have the lowest impact on the environment of any powered craft. I put electric power onto my boat because I sail on a river full of barges and wouldn't be safe without an alternative to wind power. Electric boats can gather and store power from wind, water, or solar collection and from the operation of small diesel or gas generators. So they are the most versatile. And to top it off I think that they create less vibration and put the least stress on the structure of the boat. My little plywood cat is very lightly built.

While everything does work pretty well, there are limitations to this kind of thing. An old trolling motor will only push as fast as the pitch of the propeller. And there's only one pitch available. As things are there are places on the river I can only point to. I can't go there yet. Solving all the little technical problems has been fun, but I'm still working with a hull I found here and a motor that I found there. Challenging, educational, and rewarding, but strangely limited.

Someday I would like to purpose build a slightly larger improvement of the concept. A comfortable beamy open boat with a lot of living room that handles well under sail and can also travel easily under power at similar speeds for a day or two.

A couple of questions come to mind for some of you more technically inclined. Can a system be designed to gather power from being moored in a four knot current?

And what's a henway??

Aramas
08-16-2005, 02:47 AM
The prices for the Solomon motors and gear make me laugh. It seems that anything other than trolling motor adaptions are rich boy's toys.

Lion
08-16-2005, 03:57 AM
What about pricing on the UK Lynch and Briggs & Stratton Etek licence build?

I have absolutely no feel for the pricing on this type of gear. With batteries, controllers etc, aside from all the other compromises, is it at all competitive with internal combustion?

Lion

LLaver
08-16-2005, 08:14 AM
I have also been looking at an electric system for a small sailling boat as a small auxillary motor. I have been trying to find a source of cheap electric motors that can be used for this application.

I have been trying to avoid buying a trolling motor as they are rather clumsy and expensive. I would like to take a submersible motor and build it onto an alternate rudder/outboard that sits on the existing rudder fittings

I have done internet searches for submersible motors and can only seem to find pump motors.

Do any of you know anything about these type of motors and their suitability for this use, do they produce a small enough version that can run on DC current etc.

Or even better, is there a source of submersible motors for this purpose(other than commercially built trolling motors).

Lee

willmarsh3
08-16-2005, 04:50 PM
To answer your question about submersible motors check out the MinnKota EM 44 engine mount motor or EM 54. I saw these as I was looking for a trolling motor for my Elver. I'm going with a trolling motor as they are readily available, and cheap when compared to a new gas outboard. The only reason I did not go with the EM 44 was because I did not want a fixed protrusion on the bottom of my boat.

Will.

LLaver
08-16-2005, 07:38 PM
HI Will,

I have just checked out the price of these motors online :mad: here in Australia they retail for more than twice the price they do in the US and thats after the dollar conversion ( Aus $ is worth about $0.77 US) retail price in Australia is AUS$1,285 compared to US retail price of US$429.95

Bit rude hey!

Lee

LLaver
08-16-2005, 07:39 PM
Oh and I forgot to mention, I need saltwater friendly.

Lee

Badley Built
08-16-2005, 09:48 PM
Interesting story here.....

http://www.gosolar.com/press/release/solar_boat_around_Long_Island.htm

RonB.

Badley Built
08-16-2005, 09:54 PM
And here....

http://www.outboardelectric.org/

Dan Hobson
08-19-2005, 02:20 PM
All I can say for your expense issue is buy used gear and work with what you can find. I don't know about salt water freindly or what that's going to cost you in Australia, but my guess is that you may be able to find something you can make work. Find it and rebuild it.

When installing the engine, remember that it's got to breath, otherwise the air temp expansion goes against the seals and then creates a vacuum as it cools that will suck in water. So while you run your wires, run an air tube down the pipe too. Then seal the pipe to everything. Some of the trolling motors use a pulse circuit. It stretches the battery life and controls the speed of the motor. The 2HP MinnKotta that I found for mine has such a circuit, but down inside the motor all of the primary wires (4) connect to two posts. So it's a simple immersable DC motor with a fancy circuit to make it run on less juice. I have the power head mounted inside the gunnel out of the way.

The rudder works, but I'm not so familiar with the cat boat design to say how well it works. The boat can catch a gust and round up with the most vicious weather helm I've ever seen. Do all cat boats do this?? I've seen some pretty wild articulated rudders on these things so I'm thinking that it may just be a characteristic of the boat. Frankly, I kind of like the fact it rounds up rather than wants to go over. No user intervention required, it tends to stay flat on the water.