IanD
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Posts posted by IanD
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We got a Huawei E5186 when we needed Internet access before our office was fibre connected, worked flawlessly and has all the features requested.
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Thanks guys. I was considering the TT basin as an alternative to Piccadilly Village, but might go on to New Islington Marina (I assume overnight moorings are free?) to gain a bit of time the following day and make sure we get to Slattocks -- I know the Rochdale locks are slower than the HNC ones. The Summit Inn isn't brilliant but given trip timing there's not much choice, Todmorden has several decent pubs/restaurants (Golden Lion?), it's useful knowing about the BareArts beer shop since stocks may be running low by then ;-)
On the HNC it would be nice to get as far as the Sair Inn -- or even Slaithwaite, the Commercial is indeed good -- but it all depends how far we get the first day. I restocked with beer from the Empire Brewery last time, and the Riverhead is again our target in Marsden (this is becoming a re-run in reverse of the one-way Ashton-Sowerby trip a few years ago).
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Thanks Nick -- it would be good to get up to Slaithwaite on the second night (good curry and pub IIRC) but this depends on getting away early, current plan is Brighouse Basin / Golcar Aqueduct (I think this is where you meant?) / Marsden / Standedge ==> Uppermill / Stalybridge / Ducie Street (or New Islington marina) / Slattocks / Summit / Todmorden / Sowerby Bridge.
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Even if you set date of post to "any" and last update to "any", search reverts to posts updated in the last year.
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Looks like the Mason's Arms is indeed gone, even TripAdvisor agrees -- bugger...
http://www.closedpubs.co.uk/yorkshire/todmorden_masonsarms.html
https://whatpub.com/pubs/HAL/1164/masons-arms-todmorden
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6 minutes ago, David Mack said:
The Stubbing Wharf is in Hebden Bridge. Are you thinking of The Moorings next to Shire Cruisers?
Yes, my mistake.
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Thanks for the replies, everyone. Mac, I'd read your pub cruise reports, but the rate pubs are closing or changing hands I thought I'd see if anyone had more recent info -- I knew the Puzzle Hall had closed (boo), and possibly the Mason's Arms but there seems to be some uncertainty about this, but thanks for the Red Lion recommendation. I know Stubbings since it's right next to Shire Cruises, the Shepherd's Rest looks like a good bet for our last night. Fox and Goose means the one in Hebden Bridge, I assume?
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Any recent recommendations (Ducie Street to Sowerby Bridge)? Is the Masons Arms at Gauxholme still open?
Oh I forgot, moorings nearby would help. Silly me...
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2 hours ago, Robbo said:
It takes very little power to move a boat under 4 knots (Speed over water). Most boat engines are really overpowered for the majority of the time. A Diesel engine is at its most efficient when it's ran at around 75% load, so running a generator too charge batteries you can run the genny at its most efficient level. However apart from lithium batteries where it doesn't hurt them, charging above 80% SoC is slow so doing this bit over solar, grid or when the genny can be used for other means.
i believe that it's more efficient running a diesel genny/battery/electric boat than Diesel engine alone, however I don't believe you will ever get the purchase costs back over a standard engine. So if you want an electric boat it's not because it may be more efficient, it's because it brings other benefits and that could be just that it's just quiet.
A generator typically has about 25% efficiency from 30%-100% load, according to the Victron report. An electric motor will be about 90%, charging and discharging batteries loses about 20%, so let's say this gives 20% overall efficiency for a serial hybrid using a genset.
I worked out the efficiency for a modern diesel (Beta 43) from the consumption curves, this was 34% at full revs/power (43bhp/2800rpm) falling to 20% at half revs (4bhp/1400rpm) which would be typical cruising.
So it's difficult to see how a genset hybrid could be more efficient than a diesel in a narrowboat.
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Hi all
This year's plan is to do the HNC/Rochdale ring in 10 days starting from Sowerby Bridge in August, according to Canalplan this means two and a half days (4h + 8h + 8h) to get to Marsden in time for a morning Standedge passage -- which unfortunately puts an overnight stop somewhere near Milnsbridge, leading to some questions which maybe the combined knowledge of the forum can answer...
Is there anywhere reasonable to moor above Library Lock (11E)? Is the Four Horseshoes as nasty as the reviews say? Anyone eaten in the Taaj or Bombay Tandoori just round the corner?
If not, how about mooring further up, maybe near or past Golcar Aqueduct with an evening on the boat instead of suffering a crap pub or restaurant?
The basic problem is there's just nowhere decent to moor around there that I can see, even if we do well and get past Milnsbridge I doubt we'd get as far as the Sair Inn at Linthwaite...
Cheers
Ian
P.S. Before anyone suggests taking an extra day, boat hire days and Standedge opening make this impossible, and it's even worse if we do the Rochdale first :-(
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Is there an easy way to filter out some forums from unread posts, like there was before?
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There used to be a way of excluding certain forums from appearing in "Unread Topics" but this seems to have disappeared -- is this permanent or will it reappear once the search indexing is complete?
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Hmmm never mind brass, a lump of stainless bar a suitable size is only £3.95!
(A LOT more effort to drill and tap though...)
Stainless steel is 40x resistivity of copper, brass is only 4x...
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Toilets are especially fascinating. Remote controls and/or mobile phones can be dropped down them to see if they flush away like poo does. Hard bread sticks can be dipped into them to soften them up for eating. Not a likely hazard nowadays (especially on a boat), but toast can be inserted into a video recorder as well as eaten. Many other possibilities for mayhem will be found, some previously unknown to science. Enjoy ;-)
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Beauty is in the eye of the beholder........but then again it is Livepool
Is that near Deadpool?
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The system I posted about ("power station") isn't a hybrid, it's a high-power 48V brushless generator and big battery bank/high-power inverter added onto a conventional diesel engine, for people who want more electrical power (5.5kW generation at 1250rpm) than you can realistically support with a travelpower or alternators -- target market is gas-free boats.
It's part-way to a parallel hybrid (which they also offer) but with less added cost and complexity -- obviously you can't travel on electric power, but that's not the intention. Parallel hybrids save some fuel but not as much as you'd expect because the losses in going generator -- controller -- battery charge -- battery discharge -- controller -- electric motor largely cancel out the fuel saving from running the diesel for shorter periods at higher load factor. They do have the advantage of silent travel/locking, but the difference compared to a properly silenced (soundproofed engine room + hospital silencer) diesel isn't worth it for most people.
Series hybrids (diesel generator + electric-only drive) are invariably more expensive, less reliable and less fuel-efficient than parallel ones, as several trials and investigations have shown -- in many cases such boats have been converted back to diesel.
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Wouldn't something like the Hybrid Marine "Power Station" meet the OPs requirements?
http://www.hybrid-marine.co.uk/
48V system, 5.5kW charging from engine, added solar as needed, 48V 200/400Ah Odyssey or 800Ah 2V traction cells, aimed at gas-free boats with heavy electrical use which seems to be what is wanted. Usable battery capacity (to 50%) with traction cells would be 20kWh -- cells weigh about a ton but that's just free ballast in a new boat.
Heavily sound insulate the engine bay and add a hospital silencer and it would probably be as quiet as a cocooned generator, also cheaper and much more reliable.
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Instead of all the arguing about formulae, I'm still waiting for somebody to float a length of wood in their bath to prove it. I'd do it myself but it's so expensive heating up all that water when you live in a house ;-)
[and it really isn't that complicated, all you need is Archimedes' principle and Newton's laws...]
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But the LCF is only relevant as you are using it when the vessel is floating free. The issue here is that one end of the vessel was kept in a fixed position regardless of flotation considerations.
reductio ad absurdum argument: if you tied one end of a boat firmly to the land and then let sufficient water out (supposing that the lock was deep enough) so that the boat was entirely suspended out of the water, then there would be no sinking in the manner described.
The actual situation was probably somewhere in between and it ought to be a relatively simple task to estimate the likely behaviour - but I'm too much past A level to bother!
LCF determines where you need ballast to float the boat level, allowing for where the heavy bits are and how much displacement (especially at the stern) is removed by the swim.
Once you've done this and you start to apply force to the boat (e.g. a hangup), the amount of bow rise/stern sink is only set by the area of the hull at the water surface at bow and stern because this sets how much water is displaced -- good old Archimedes again. Since the counter will normally be under water by an inch or two, this means the change in displacement by lifting the bow and sinking the stern by the same amount are very similar since they are similar shapes, LCF or LCB has no influence on this. With a typical narrowboat draught the rise and fall at the two ends will be similar to each other, even allowing for differences in hull shape.
Exactly the same applies for lateral tipping, the distance one side goes up and the other side goes down will be almost the same. If you work out the numbers, the "stiffness" in the sense of amount of vertical movement for a given amount of force is the same for both lengthwise and widthwise tipping -- if compared to standing in the middle of the boat you stand on one gunwale and it drops by X (and the other one rises by X), standing on the stern will also drop that by X (and raise the bows the same amount). If you move to one side of the stern it will drop by 1.4X and the opposite bow corner will rise by 1.4X -- the distance is bigger because the "stiffness" is less, but the up and down movements still balance.
(actually these numbers ignore the overall vertical movement of the hull, adding a weight pushes it down -- but a hangup pulls it up...)
So it comes back to the fact that if a boat gets hung up at one corner and the water level drops a given amount, the loss in freeboard at the opposite corner will be somewhat less than this -- not almost double as I said before, that was wrong :-)
If you don't believe me get a rectangular piece of wood, float it in the bath, draw a line round it at the water surface, and have a play by lifting one corner. I guarantee that after all these years Mr. Archimedes is still right ;-)
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This only holds if the boat does not heel over!
No, I allowed for that -- read what I wrote more carefully. Without heeling the stern sinks less than an inch if the bows are lifted by an inch.
Is the answer just that the boat was tilted not just from bow to stern, but from port to starboard too - so that the starboard cant at the stern was significantly lower in the water than it would have been with a straightforward hang-up at the bow plus a few inches' drop in water level?
I've re-read the original description of the incident and the CRT staff member wasn't offering "10 inches at the stern for 1 inch at the bow" as any sort of general rule of thumb; he was estimating that in this case, because of the way the boat was wedged, each 1" drop in water level at the bow had led to a 10" drop at the stern.
Very possibly, but the result is still less than 2" stern drop in the opposite corner to a bow hangup.
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Thank you for explaining this so well.
I am shocked at how much resistance there is to enquiries which are aimed solely at improving our understanding of how this accident came about.
Maybe because the repeated claim about the water falling "a few inches" (after hangup but before the boat sank) cannot possibly be correct? For sure, the 10:1 claim from the "CRT employee" is complete rubbish -- just because somebody works for CRT doesn't mean they know what they're talking about...
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Regardless of what some anonymous CRT bloke said, ye canna change the laws o' physics...
If you grab the bows of a floating boat and pull them up by an inch (but keep the boat level side-to-side), the stern will drop by about an inch -- shape of swims etc have little effect since the counter is underwater, the increased displacement at the stern balances the reduced displacement at the bows. This ignores the upwards pull from whatever is doing the lifting reducing the overall displacement, so the stern will actually drop by less than an inch. If you grab one side of a boat and pull it up by an inch, the other side will drop by less than an inch for the same reason.
Put both these together to get the worst-case -- likely with a lock wall hangup at one end of the boat -- and the result is that for every inch the water level drops after hangup, the opposite corner of the boat will drop by less than two inches. For a boat with 15" freeboard, the water level would have to drop by at least 8" after the hangup to reduce this to zero.
No amount of boating experience or "common sense" will change this -- as was said during the Brexit debate, you're entitled to your own opinions but you're not entitled to your own facts...
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For people that are stuck to (their) old ideas, all the changes that have been done over the years, and that took a lot of time to be accepted i.e.:
The change from wooden to steel (iron) boats, with some hesitation at first still using a wooden bottom.
Welded instead of rivetted construction, welds were something that many boat people had difficulities with too.
In the future we may see more "Shilling" rudders being installed on narrowboats, for the time being, I only know of one.
It all takes time, but maybe one day we will see a new kind of narrowboat arriving, with less draft and better underwater shape, as they don't have to carry cargo anymore for which the traditional shape was developped.
Peter.
Controversially, I suspect this would also show that the double-curved Josher-style bows so beloved of many people are a waste of space and money (though pretty). If they worked then similar shapes would also be seen on fuel-critical hulls like tankers and container ships, but they're not -- their bows are always quite bluff because on slow-speed vessels this doesn't increase drag or make a bigger wake. The reason is that the water in front of the bow stagnates and forms a "virtual bow" that the water then flows smoothly around. It's the same reason even high-speed fish and submarines are blunt at the front...
The stern however is a different story, here they take great pains to get a smooth flow of water past the hull and over the prop and rudder because any sudden changes of cross-section (or rate of change i.e. sharp edges) cause turbulence and drag. Most narrowboat hulls are terribly designed in comparison, and don't even follow the basic "good-practice" rules for things like skeg/rudder shapes and prop clearances. It's true that a canal is very different to the open sea, but the same rules of getting smooth water flow apply equally in a shallow/narrow channel -- however the optimum hull shape could well be different.
Trouble is that as was pointed out, due to fitting overpowered diesel engines nobody's really interested in doing anything about all this -- most boaters don't understand anything beyond how "nice" a hull looks, most hull builders have little or no knowledge of issues like this, and even if they did almost nobody apart from a few geeks like me would care anyway :-(
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Meanwhile if you have no concept of where the channel is likely to be and can't read the clues the boat constantly gives you regarding your speed and position, you'll still struggle.
Bottom line, your boat's a moving hole in the water. If there's not enough space around you for the water to get past and refill it, all calculation and theory is irrelevant.
It's not irrelevant, either making the hole smaller (lower displacement) or better shaped (hull form) will still help make the best of a bad thing...
Canal & River Trust sets out plans to review boat licensing
in General Boating
Posted
All unpowered RFID-type systems have a range of at most a couple of feet, and the laws of physics say this can't increase by much.
Remote tracking of boat positions needs a power source, and a radio transmitter/receiver (what band? licensed how? what radio standard?), and infrastructure to deal with all this (cellular? something unique?).