Phoenix_V

This was my understanding but following the suggestion in the other thread that props were being specced to maximum torque, I wondered what was actually being done in the real world

Arent most(all?) diesels governed so that off load max rpm is just a couple of hundred more than on load?

Assuming no other problems if the prop exactly matches the engine it will enable the engine to rev just to it's rated maximum and no more, if overpropped by definition it will never reach that figure so all you need is a rev counter. If it's underpropped it will also make max revs and then the governer will stop it going faster unless its a petrol engine then you do have a problem.

I have always assumed that it is usual to prop a boat so that it can just reach engine maximum revs, a recent thread suggests that on canal boats (at least) overpropping to the extent that only 50% of max rpm can be reached is quite common and acceptable. It would be interesting to find out what is being fitted out there

Despite extensive reading on this subject my knowledge is little and often contradictory, but as I understood it it is unusual to overprop to the extent that the engine achieves less than 80% of max rpm. Reasons for overpropping include matching the power curve, better fuel consumption, lower rpm for a given speed (and hence quieter engine) Reasons for not overpropping include not being able to get full power from the engine (though many narrowboats are overengined anyway) and being less likely to overload the engine in trying to get to max rpm. I am shopping for a propeller at the moment and would expect the supplier to discuss with me the ramifications if deliberately over propping. I take it the Op's propeller has been on from new and has never done more than 2000rpm?

ASAP supplies

I've used polyurethane wood glue no problems so far

No one dredges any more the cost of disposal is to high, do what everyone else does and move the silt back into the main channel either as has been suggested with shovel and waders or use the prop in reverse to gently blow it away, regular movement of the boat will also help. If you have a keel cooled engine it is hard to see how it would be damaged if this is only silt.

Glazing a wheelhouse to comply with cat c I was told that 5mm toughened was acceptable but in laminate would need 7mm, went with toughened to save weight. I was also told that windscreen wipers etc are less likely to scratch toughened.

It is one of the odd quirks of marine insurance law, the value of the boat is agreed at the onset of insurance and in the event of damage unless repair is cheaper that is what they have to pay (less the salvage value if you keep that) Preferable in many ways to other insurances where you have to argue the value post event but, insurers will be careful not to insure the boat for more than it's worth and hence require a survey for valuation as well as confirming sea worthiness. We have used the Simpson scheme mentioned above on a small woolwich and found it reasonably priced with not too onerous survey requirements, never made a claim though.

I suppose if they spent the money intended for enforcement of the Lea and Stort mooring scheme on dredging instead then the problem might be sorted and the boats could move!?, but then of course they would have no money to force the boats to move, still seems less of a waste of money though

I have no reason to doubt what you say, but it is unfortunate that in BW public meetings whenever anyone says "you cant do that" they tend to reply "oh yes we can - Davies says so" consequently why we are keen to keep the draft in public circulation.

which ones?

This does not appear to be the full judgment either compared with the earlier draft on Smartguage's website, perhaps someone in the know can explain how this wroks

From the BW website, the consultation period on the proposals has been extended "We've had an excellent response to date but in light of extraordinary events – spate of public holidays and local government elections – we've pushed back the deadline to 31st May to ensure that all interested parties have ample opportunity to respond." Having followed this it seems to me that the local resident boaters have submitted numerous comments supporting their position as have those leisure boaters who are all for clearing the towpaths. There seem to be relatively few responses regarding those aspects of the plan which will affect the rest of us. i.e. the right to moor for 14 days removed from a large part of the rivers and the redefinition of place to give only 6 on the entire river. Also the punitive overstaying charges. Just a suggestion but maybe boaters from other parts of the system who anticipate visiting the Lea and Stort and might be affected by this whether continuous cruiser or not might care to submit a response to the consultation!

Which is what? because everyone I have seen offends someone For clarity I was not blaming the boaters, they didnt close our facilities BW did.

and they have hidden the lavender boat right round the back

Just trying to use shorthand please insert CMer towpath dweller whatever as desired.

I bought a copy of the Yachting Monthly tests, this was mainly looking at folding props butthey did include an axiom and a standard prop. The Axiom did well astern bollard pull 181kg against 173kg standard stopping in 7.7 against 9.3 seconds propwalk was good too at 9.3% against 13.9% However ahead max speed was 7.1 knots against 7.5 on the standard bollard pull 233kg against 264kg standard I have asked Axiom about this and they say that the competition was overpropped and if they had overpropped they would have done better ahead. So inconclusive here. Most of the information out there is either very technical or way to simplistic, I have just about got my head around propeller diameter and pitch sizing but propeller area calculations elude me. However I wonder if on our boats often the problem is not propeller area. As I understand it the area of the blades does not matter a lot until you get to the point where you are putting more power in than a given area can cope with and the prop cavitates. This would explain why 2 props of nominally same diameter and pitch perform differently if one has a lower area and fails to take the power? The prop suppliers I have asked to quote me have been unforthcoming on this point I suspect most have a limited range of prop sizes and sell what they have rather than what you need, Crowther have a good reputation but the term "high efficiency" does not seem very specific.

It is widely assumed and not denied by BW that they have closed many of our local facilities to annoy/discourage the local ccers Oh quite so but i hadn't realized it had gone national

I had assumed that the closing down of facilities was a local thing part of BW's games with the CCers but perhaps this is a cost cutting exercise they are rolling out nationwide, it would really be worthwhile listing closures both to update our cruising guides and if there is a secret policy of closures challenging it. keep them coming. I thought Feildes had reopened does anyone know. The tap is right by the disposal, I dont like using it for filling the tanks. Does anyone know if Harlow marina facilities are still available to passing boaters or have they been closed like Limehouse? Years ago when facilities were fewer BW used to make it a condition of the lease or access agreement for boatyards that they had to provide free water and disposal for passing boaters has that gone by the wayside?

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i didnt know that do they give the 10% prompt payment on moorings as well as licenses? Where I am building the new boat they only seem to take cash

1 no 2 no

1 The site mods haven't made their position clear. 2 Sorry but I am happy to discuss issues on this forum but i dont make personal remarks and i dont expect to receive same having been on here for some 5 years i dont take kindly to being rudely told by someone that appears to have been here 3 months to leave if i criticize one decision of the thousands the hardworking mods make