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Scholar Gypsy

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Everything posted by Scholar Gypsy

  1. Facebook (I think) sent me an item recently about one of the early US aircraft carriers. They had a load of planes lined up and tied down, facing to starboard (on the bows) and to port (on the stern), and then ran the engines and the boat span nicely. Of course I can't find it now, when it might be useful. My only other tip - which worked for me a few years when pinned in Whitttlesea, was to push the bows over to the other bank, and get the bow stuck in the helpfully provided gloopy shallows. The boat stayed put for long enough for me to get to the other end and then motor off. An occasion where shallow water is helpful! A cable tie around a convenient tree might have worked....
  2. I will ask my son, who is a maths teacher... If you want a rough estimate, then the movement of the boat (forwards going up, astern when going downhill) is M = L - (L^2-h^2)^0.5 ~ 1/2 . h . h/L (to first order, as h/L <1) So if h is 8, L = 32, then M is about 1. (The pendulum result depends on the fact that sin (x) ~ x for small x.)
  3. For Sandford (which is tricky) I had a second bow line, going back from the bow, of similar length to the stern line, and tied to a bollard. That enabled to hold the boat against the wall, just. And it was hammering down with rain...
  4. I did the whole river from Teddington to Lechlade last summer. Going uphill I do this: get off the boat at the stern, with a stern line and a long light line that lies on the roof and is tied onto the bow line. Stop the boat completely before doing this & then stop the engine tie off the stern line, a reasonable distance astern of the boat tie off the bow line, a reasonable distance in front of the boat close the bottom gates start the automatic sequence for filling the lock take in the slack on the bow line as necessary Going downhill Use as long a stern line as possible, and tie it off to a bollard (25 feet plus) Do NOT secure the bow line, but make sure it stays on the bank (eg wind the end very loosely around a bollard, or put a bowline in the end and drop it over a bollard alongside the boat) Close top gates, operate bottom sluices Tend the bow line, take up the slack and then letting it out as necessary In both cases, Pythagoras is your helper. For example with a 25 foot stern line between the boat and the bollard, then as the boat goes down (or up) 8 feet (more than most locks) the boat will move forwards/backwards about 16 inches. Here is Shifford, one of the deeper locks on the Upper Thames (and hand operated of course)
  5. And both locks appear to have ropes/chains for opening the gates?
  6. I think they are electricity poles, and I agree they don't look very French. https://en.wikipedia.org/wiki/Utility_pole
  7. I did think, after watching the final episode, that the narrow boat must have had a rather powerful inverter; and probably a composting toilet.
  8. In the 5th episode of Boat Story (BBC iplayer https://www.bbc.co.uk/iplayer/episode/p0glcy88/boat-story-series-1-episode-5 at 56:30) there is a shot described as the Canal du Midi. (It's a rather complex plot). Looks more like the Leeds and Liverpool to me, with CRT bollards approaching the lift bridge. Any ideas >?!
  9. As well as the width issues -- as others have explained the Northampton Arm locks are 7' wide -- you should also check the draft (how much water you need) and probably more importantly the air draft of the boat (there are some quite low bridges around.,,)
  10. This would have been before the half tide lock was built at Richmond (1890s), and so would have dried out fairly comprehensively. It's the annual draw down at Richmond at the moment, until Monday 4th , and is well worth a visit around low tide. https://www.pla.co.uk/assets/u19-23.pdf Photos here: https://scholargypsy.org.uk/2017/11/18/what-happens-if-you-leave-the-paddles-open/
  11. I went through this summer, in the middle of the festival. It was very fine. I spent about two hours filling my water tank, and having a nice long lunch stop. A procession of boaters kept arriving, and I let them fill their portable drinking water containers .... ... and I bought a nice belt as I went past this boat ...
  12. The non-tidal side - strictly speaking the level at City Mill lock, a few hundred metres above Three Mills. If the water is above this level, then the headroom on the A11 road bridge is too low. Also the water level may be above the level in St Thomas's Creek - in which case the lock (which only has one pair of gates pointing that way) would not work either. It's quite a complex system, with not a lot of room for things to go wrong.
  13. Not very relevant, but this graph shows how Three Mills lock on the Olympic waterways was working on Wednesday this week (I was operating the lock after the FBW protest cruise!). There was a strong tide, which mean that the weir lifted (the red line) at 1300 to keep out the tide. Then the impounded level (between Three Mills and City Mill) gradually rose, filled with fresh water from the Lea, which meant City Mill lock could not be operated (it locks out when the water is at 2.9m). At about 1530 the weir lowered automatically, and an hour later the boats were on the move - having spent three hours in the lock!
  14. Yes, I had one door bolt that was a bit sticky....
  15. My stern tube now drips much less after a week out of the water in September (for blacking). Very strange!
  16. This is the one I had in mind at Alwalton - a new stretch of river was built to take out the kink! https://maps.nls.uk/geo/explore/side-by-side-old/#zoom=15.8&lat=52.55889&lon=-0.32293&layers=168&right=193
  17. I think that's a flash lock, ie just one guillotine gate. When a boat wants to transit it is lifted and the boat either zooms downstream or is winched upstream as the levels equalise. I have seen photos of a very similar structure on the Brandon Ouse, near Hockwold. The remains of that are just about visible. I think one can also see the old lock structure downstream of Awalton, though I may be imagining that. One certainly can just below Lower Wellingborough lock (which looks like a 1970 structure rather than a 1930s one).
  18. Helen is of course, as Chief Executive, representing the views of the Conservators (who employ her). I do think this subject has got somewhat garbled in the press coverage. There is no intention on the part of AW to "stop navigation on the Cam". But (as I said earlier) there is more to do to understand the precise impact (if any) on navigation of the proposed works, during construction and then permanently, and to ensure that the legal powers granted to AW are no more than are necessary. The other point I should add is that there are of course lots of other impacts of the project, for example on water quality and other environmental aspects, but these are primarily a matter for other agencies rather than the Conservancy.
  19. I hope I can offer some reassurance here, as I am a Cam Conservator. We have been discussing this a lot for quite some time (and certainly since I joined in January 2023), to understand the nature of the structure, and the impact on navigation a) during construction and b) when built; and what that means for the powers AW are seeking. We have submitted lots of questions to Anglian Water, and as you can see from this article the Planning Inspector has just held the initial scoping meeting at the start of the process of approving the works. The Environment Agency will of course have a major interest - we are just the navigation authority. Here's a drawing of the proposed outfall - on the opposite side of the river to the existing one which will be removed. It does involve works to protect the bed from scouring, but the bulk of the concrete structure is actually behind the river edge. We are also interested in the rest of the project, which collects sewage from as far down as Waterbeach and pipes it south (upstream) to the new STW. This means that a number of smaller existing works (Waterbeach, Horningsea) can be closed, and a new tunnel built under the river between Bottisham lock and Clayhythe. PS The subject of this thread is somewhat misleading, IMHO. PPS here are some photos of Jesus Lock, currently with no gates ... https://scholargypsy.org.uk/2023/10/26/jesus-lock-cambridge/
  20. That's a tougher test. For example if you make a modification to your boat there is no requirement to get a new certificate, but the work still has to be done in a way that maintains scheme compliance.
  21. Thanks for the comments. There is (of course) a cover that fits on top of the lot, to avoid shorting. The thin wires connect to a battery charger (not in use now I have solar), and a sulphator. There are a number of fuses just out of shot (eg for the Smartgauge, solar, and bilge pump).
  22. CRT licence terms and conditions "The Boat must always comply with Boat Safety Scheme requirements" Section 6: https://canalrivertrust.org.uk/refresh/media/original/43943-general-terms-and-conditions-for-boat-licenses-june-2021-searchable-file.pdf Prompted by my recent full survey, I finally got round to strapping the batteries down. They have never moved an inch in 30 years, despite some quite rough water conditions....
  23. I was going to quote my Craftinsure policy but @nicknorman beat me to it. I guess the problem the insurers have is that they have literally no idea how competent a particular skipper is - as we don't need any licence etc. The craftinsure underwriters were sensible when I did a Wash crossing a few years ago, ie a list of extra conditions which suggested to me someone who understood what the risks were on this trip, and what mitigations were sensible and possible. It's worth noting that on some rivers - the Nene is a good example - the whole river goes on red even when the problem is fairly localised (or as with the recent storms, as a precautionary measure before the significant rainfall has actually happened). If you know the river then moving in those conditions is not reckless (I would argue). The EA are working on this, but it's not a straightforward issue.
  24. This website provides some practical advice on how to get there from the canal system at Northampton. It includes links to various guides and websites. There's a great list of moorings above, I am moored at Cathedral in Ely. https://goba.org.uk/a-guide-for-visitors-to-the-east/ PS you can also get to the rest of the system by crossing the Wash to Boston and Lincoln.
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