Up-Side-Down
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Posts posted by Up-Side-Down
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19 minutes ago, IanD said:
Prop power is proportional to rpm^3, so 3kW needs about 600rpm. That's what I've seen, not just theory...
There undoubtedly is, but it would be massive, expensive and heavy -- probably about 100kg since mass and rpm are roughly inversely proportional at a given power level.
Finding one available off-the-shelf might be difficult though, even ones running at 1000rpm are few and far between...
I'm more than happy to take your word for it and grateful to be able to share in your experience. You've demonstrated that in my case direct drive isn't a viable option (which is exactly what I wanted to explore, if only to eliminate) and confirmed that the only realistic way forward is belt drive. Thank you very much for moving my quest forward in one giant leap!
4 minutes ago, David Mack said:Is there that much shaft offset with the two UJs?
If so I would have thought a plummer block and support bearing at the inner end of the propshaft to take the thrust and side load, then an aqua drive coupling or similar to the motor.
5". That sounds like a good engineering solution. Thank you.
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17 minutes ago, peterboat said:
I would say efficient brigade! I have been chased by President after pulling her off the bottom, bloody quick is what I think!
Even at 22 1/2 tons and a 2' 9" draught I can do bloody quick too! I just have to rev the engine above 1000 rpm!!
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18 minutes ago, magnetman said:
Prwsumably this is a replacement for something like a JP2 which is producing around 13.5kw @ 500rpm prop speed (2:1 box).
A common install on narrow boats.
So is there an equivalent low RPM motor out there somewhere?
I can see it being large diameter.
Same ballpark. It's Ford-based Beta Tug putting out 35 HP and 105 ft lbs of torque. The prop is a Crowther 'high performance' model matched to the boat and engine by Crowther's themselves. Think something slightly north of 22 x 22! As you'd expect from Keith, it's a spot on combination and replaces a 22 x 20 affair which never made the engine work proper hard.
That's my question, precisely magnetman and for all the reasons that you've gleaned! The other route is the one that peterboat has ( and is) travelling and CL's latest offering does excite me. Much as I'd like to eliminate the drive belt, I can see its advantages, both as a fail safe mechanism (possibly made redundant by CL's new controller design?) and in the case of my installation, allowing me a greater choice of locations for siting the engine.
Yes, I do have an engine room but that's going to be re-purposed (sort of) and I do have concerns about the lateral forces on an electric motor front bearing imposed by an 8ft prop shaft and its two UV joints.
All comments on these points much appreciated.
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15 minutes ago, IanD said:
The motor is a custom one from Engiro, the closest off-the-shelf model is the 205W-12013 which is rated at 14kW/1080rpm. This needs a prop very similar to a Beta 43.
Since motor power/voltage is proportional to rpm, there's no way you'll get 15kW at 350rpm with direct drive -- which would also imply a massive prop...
Thanks for that, Ian. I'd be very happy with 3 kW at those revs. I still need to get my head round thinking in terms of power/voltage being proportional to rpm as you point out ... I'm getting there slowly! And yes it is: I'm a paid up member of the large/slow/efficient brigade!
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7 minutes ago, IanD said:
Those numbers are very reminiscent of the "1000W" power claims on cheapo amps and speakers, which bear no relation to reality.
Short-term peak output (usually for tens of seconds) is not much use for boats (though it is for cars) because the time you're really going to need high power is going upstream against a current, and you'd better be able to sustain that for at least 30mins or an hour. Which funnily enough is how reputable motor suppliers specify theirs... 😉
Direct-drive prop motors are bigger and heavier than high- speed geared ones (like Tesla use) because of basic physics; the (50kg) PMAC one in my boat rated at 48V/15kW/1000rpm is also rated at 96V/30kW/2000rpm, but that's much too fast for direct prop drive in a narrowboat. Higher-voltage motors like EVs use spin even faster amd generate even more power.
Which motor did you settle for in the end, Ian?
If I follow the direct drive route where I am looking at around 350 rpm on the prop from a 15 kW constant output motor, are there viable contenders out there? That would be to avoid gearing the drive down via a belt, Lynch-style.
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39 minutes ago, peterboat said:
You are welcome, the 155R is 25kw continuous and 50kw peak so 67hp peak?
That's what you're running, I assume (in a widebeam)?
How many KWh does that draw at sensible cruising speeds in deep water? I'm looking at something in the order of 15kW continuous and 30kW peak.
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15 minutes ago, peterboat said:
My single motor pushes my widebeam along, I know Cedric so contact him direct, he is in India currently, they are finishing testing on the motors. When that's done I will talk to him and Arvind about the final specs.
Cedric produced a big axial flux motor a few years ago a it was very powerful James a friend has one in his 70 x 13.5 widebeam on the Thames, it pushes it along nicely I think it's a R155?
Thank you.
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Sounds like it will do the job and his controller sounds interesting too. Do you contact him via the Agni website? What is the nominal power output per unit and does he twin units on a frame for additional power as Lynch does?
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I'm a great admirer of CL but not so impressed by the politics that followed in his wake. Delighted to hear that he's developing his original concept and the outcome sounds very exciting. Indeed, it sounds exactly what I will be in the market for in about a year's time as long as we're talking 48 volt. I'll be wanting a max of 750 revs at the propeller and something like 375 revs for normal cruising. Am I in with a shout do you think?
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24 minutes ago, peterboat said:
I am running a nominal 72 volts on my system which fits nicely with Julian's regs and the ones I researched with BSS before doing the conversion. My latest BSS brought up no issues with the voltage also Lilesons who build panels and control equipment said my system meet the current UK regulations
What's the drive in your case peterboat?
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On 23/10/2023 at 17:55, magnetman said:
Cor that is shocking !
At the end of the day an average narrow boat probably needs about 5kw for most porpoises perhaps going up to 10kw for unusual circumstances.
If it was 48v that would be about 100a-200a. Seems manageable.
One thing which seems interesting is the ePropulsion inboard power units all seem to be the same weight.
I am led to wonder if perhaps they are all actually the same thing with various limits applied via the software.
Maybe not but one would think a 20kw motor might be heavier than a 10kw motor.
You'll find something similar going on within the Lynch electric drive ranges too with just the voltage of these DC motors differing.
On 23/10/2023 at 17:55, magnetman said:-
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On 03/10/2023 at 17:21, Sailbadthesinner said:
Actually a solar powered electric propulsion live aboard continuous cruising boat is viable for at least 6 months of the year.
I know because we have done it for the last 3 years in a grp cruiser. Each winter she is stored ashore and we go home.
Note that this is solar only, without plugging into shore power anywhere. Cooking is also by electric. With a generator and stove 12 months would be possible.
I admit it involves getting used to a simpler lifestyle without all the luxuries and conveniences of home but isn't that what boating is all about?YES
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When ignorance is bliss, t'is folly to be wise .....
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Very rare to come across a back cabin stove these days but have just stumbled on this which is pretty much identical in size to my CI Epping. Looks like it's pressed steel rather than cast, however: https://www.amazon.co.uk/JIAOCKJIAO-Rectangle-Efficient-Supports-Multiple/dp/B0BHHJSGYV/ref=sr_1_105?crid=10K5KJLTK4SPT&keywords=solid%2Bfuel%2Bboat%2Bchimneys&qid=1690728786&sprefix=solid%2Bfuel%2Bboat%2Bchimneys%2Caps%2C219&sr=8-105&th=1.
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1 hour ago, algwyn said:
Does anyone know if there are any boater showers on the River Avon please
Not really replying to my own post lol just thought I would add that we are presently at Eckington Wharf heading towards Stratford
There are no showers provided by ANT as such. However, Hampton Ferry Marina/Raphaels at Evesham are geared up to provide showers for boaters. They can contacted at Hampton Ferry Boat Lane, Evesham WR11 4BP (01386 45460/442458; www.hamptonferry.co.uk). Also a laundrette.
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37 minutes ago, StephenA said:
When ours failed (Seals went and it started leaking through the tell-tale) we took it off and measured the impeller size and the shaft length and then phoned Calcutt as the local motor factor in Market Drayton isn't open any more.
Sounds like a plan!
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1 hour ago, Tracy D'arth said:
Several on the notable auction site. There is a common one and a few engines with another version. That is a rare one.
A motor factors will be able to match it to yours and at a vastly lower price than a chandlers.
Many thanks for this.
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6 minutes ago, Tracy D'arth said:
On old 1.5D it was a plate rivetted on the top of the block on the pump side but after all this time it is highly likely to have gone missing.
Why do you need the number?
To get a new water pump
Just now, Up-Side-Down said:To get a new water pump
But maybe Calcutt won't need any more detail?
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As above: can anyone tell me where to find it please?
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9 hours ago, MtB said:
That pretty much sums it up. (Not that I've heard of Legend Boats either until now!).
Build quality new was shyte but the point is provided you buy one quite a few years old, all the crappy build problems will usually have been ironed out by the owners in the interim. Stuff like leaking windows (a big deal if you have them!), dodgy gas installations, wiring problems, all the paint falling off etc etc will have been fixed and if not, will seem like less of a problem on a ten year old second hand boat rather than new.
Would this be 'Ledgard Boats'?
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10 hours ago, Leap of faith said:
Hello, just wondering could anyone tell me whether the Perkins 3HD46 MK2 is reasonably easy and inexpensive to get parts for?
Much appreciated.
See
I believe it's the same or similar to the engine fitted to a range of Massey Ferguson tractors such as the MF 35; MF35X; MF 135; etc and spares are very readily available for it. I have a version fitted in a rough terrain forklift and have no trouble getting spares and service items as there is a buoyant market for bits amongst the classic tractor brigade.
10 hours ago, Leap of faith said: -
Where am I allowed to mention that I've got a pretty much pristine example of a BD3 engine for sale with just over 1300 hours on the clock? All 35 hp x 105 ft lb still very much available ....... . I can even make the appropriate bits shiny again with very little effort. Going electric is the explanation btw!
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www.komoot.com is often very useful as you specify the sort of surface you wish to use from roads through to mountain tracks.
1 minute ago, Up-Side-Down said:www.komoot.com is often very useful as you specify the sort of surface you wish to use from roads through to mountain tracks.
1 minute ago, Up-Side-Down said:www.komoot.com is often very useful as you specify the sort of surface you wish to use from roads through to mountain tracks.
Not specific to Warrington! This link is somewhat more UK-wide: https://www.komoot.com
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4 minutes ago, peterboat said:
BPs, Esso and other oil companies involvement is never good and is generally totally untrustworthy
I think that's a pretty acceptable generalisation!
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One stop shop, plug and play, Electric propulsion for NBs and WBs
in General Boating
Posted
What's the likely ballpark figure for motor and controller?