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Scholar Gypsy

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Posts posted by Scholar Gypsy

  1.  

    And I found the duckweed! It's piled more than a foot thick at Denver Sluice, including in the lock, where I locked (up!) towards Salters Lode yesterday.

     

    Heading towards Peterborough tomorrow morning, so hope the Nene is down by then. Trouble is my computer has died, so I can't get e-mail SSA alerts, except where I can find a library. (my phone is a dumb phone.) I thought I'd registered for text alerts but haven't had any yet.. My little boat wouldn't make much progress on the Nene against any sort of flow.

     

    I'd be happy to pass on any SMS alerts - I am registered. If you are interested please PM me your mobile number.

     

    I am watching the system very closely at the moment, as the boat is moving on the Bedford Ouse and I am in London!

  2. I have a vague recollection of a lift bridge in Oxford that joined a works to its car park. Can anyone confirm this and where was it (having come down today I think it was 239) When was it removed?

     

    Yes it connected two halves of a factory, that I think was either part of BL or supplied it with parts.

     

    I used to go there for meetings of the local IWA branch in the 1970s. The electric bridge was operated by factory staff, and left open overnight and at weekends.

     

    Not sure when it was removed and replaced by the new bridge connecting to the housing development to the west of the canal.

     

    ETA: Unipart. See 1998 press article:

  3. Its been up and down like a whores draws at titchmarsh. Two boats on 48 hour moorings.

    Rescued my brothers Genny from his storage container just in case....

     

    Its been quite high on the Ely Ouse, Dad and Brother haven't got far these last few days, sought refuge in the cutter and 5 miles from anywhere!

     

    My sister has got as far as Holywell on the Bedford Ouse today, things seem to be calming down a bit. They have seen two seals there today (or maybe the same one twice).

     

    The water level was very high at Earith (tides as much as fresh), and this had led EA to issue a notice to remind people to make sure the guillotine gates at Brownshill are UP before they attempt to enter the lock.... Apparently someone (not my sister, of course) forgot to check, and came to a rather abrupt halt.

     

    ETA: Islip levels here

  4. Thanks again for advice. Just had a helpful chat with Denver, and made a booking for Monday 18th.

     

    There may not be enough water on the next day, a Neap tide

     

    If anyone wants to join in & make a little convoy, please let me know. RV 1130.

  5. Lots of paddles over the system don't have reduction gearing. In fact I would say a majority of ground paddles don't.

    indeed so. That is because most ground paddles are only 3-4 feet below ground level, while those on a staircase are rather deeper. I would also expect those at Foxton etc to be bigger, as they are singles targe than pairs. Both factors add to the weight to be lifted.

  6. I think the shape of the river/estuary might come into it. Wide at Southend and narrow at Teddington. There is no restriction to the ebb but the flood is restricted like sand flowing through an hour glass.

     

    I don't think this is quite right. If there was no fresh water flow coming over Teddington weir, then the flood and ebb would each take the same time, a bit over 6 hours. (nb this is a statics result, obviously true if the tides were slowed down by a factor of 10 or 100, in which case the flow is reversible. in practice there will be some complex dynamic effects eg causing HT to be later at Teddington than at London bridge.)

     

     

    However in reality, more water flows downstream past a given point on the ebb tide than flows upstream during the flood, and that will explain why the ebb lasts for longer. the effect becomes more pronounced as you move upstream (ignoring water from tributaries).

     

    nb to prove this requires some computer modelling, or else a large water tank. I went to see one of the latter many years ago st the research station st Wallingford, being used to model a possible airport at Maplin...

  7. Bleeding hell, and they told me that this was a really relaxing way of life with little worries. :judge: I take it I can purchase said keys if and when I get near the Nene. Will the lockies tell you what one might need before they let you through?

     

    Thanks for the info by the way.

     

    D

    No. you are only likely to meet a lockie at Stanground.

     

    She will make sure you have all you need to get through the Middle Level, though.

  8. I've never been on the tidal Thames on a small boat, just the odd trip on big passenger boats and observing the flow from bridges/embankments, but I imagine you have to really concentrate and plan ahead when going downstream at the peak flow of an outgoing tide. How fast can it get potentially, I shudder to think?

    about 4 kts, in the narrowest part of the river, near Bkackfriars.

     

    the excellent website mentioned (indeed written) by Leo No 2 above points you to all the relevant guides,

    including PLA notices which tell you which arches are closed.

     

    I find the most exciting moments are when a tug & barges is going through

    the same arch as you. As the isophase light makes clear, you need to give

    way. that is when the VHF is invaluable. the only way to stop & wait is

    to turn around & stem the tidal flow.

  9. the spare wire probably goes to a temperature sensor, on the engine near the thermostat housing. Do you have a temp guage on the control panel

     

    try touching the connector to bare metal surface. that will probably make the alarm sound, or the easter

    light go out. any such symptoms will aid diagnosis.

     

    (my boat has two oil sensors and two water sensors: one of each is connected to a dial & the other tts the alarm buzzer.)

  10. The most efficient heat exchanger configuration is when the two flows are in opposite directions (counter flow) i.e. the incoming hot coolant from the engine is used to top up the temperature of the nearly hot domestic water, while the cooler coolant preheats the cold incoming domestic water. So domestic water in at the bottom and out at the top, engine coolant in at the top and out at the bottom.

    Thank you. as I say, revision needed .....

  11. yes, on reflection that seems right. The water cools as it passes through the coil, so it tends to sink. Thanks.

    as the water is pumped (by the engine) through the calorifier, I think it would be more efficient (in terms of maximising heat transfer) for the water in the coil to flow bottom to top. but the effect is likely to be marginal. (I need to revise my thermodynamics)...

  12. NB the pressure relief valve is v important, otherwise something will break/explode when the water heats up.

    ours empties into the drain on the washbasin.

     

    I would also suggest adding a thermostatic mixer valve to mix hot water

    coming out of the calorifier with cold water, to produce nicely warm water.

    this greatly reduces the risk of scalding (depends on your engine operating temp of course).

    well worth about £20.

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