cheesegas

I think @AJLElectronics was the rather dim chap who said that petrol poses no greater risk than diesel on a boat. https://www.facebook.com/share/p/1J2eE9NZRM/?mibextid=wwXIfr Wouldn't take what he says too seriously!

This is a widely misunderstood thing by both consumers and insurance companies I feel. LiFePo4 is a type of li-ion battery, just like NMC is a type of li-ion battery; those are the ones used in phones. Li-ion is a blanket term which covers a whole family of lithium based batteries. All these are types of li-ion battery - LiFePo, NCO, NMC (those two are the sort used in phones, scooters and e-bikes), LCO (newer phones and things with small cells), and there's a few other less common types too.

I have a similar boat, a 19' Colvic Watson with probably the same engine as the Nelson - a 20hp Penta MD7B. Mine is very recently purchased though - spent a couple of months on the hard standing fixing bits and pieces before launching it, and I keep it on a mooring on the lower Thames. I use it for pottering around the Thames Estuary, 20hp is fine for that, being a displacement hull the small engine gets it up to 6-7knts easily and it'll happily cruise all day at that speed. More throttle just results in more noise! It's probably underpowered if you have a destination in mind offshore though, it'll take a long time to get there. It is however very stable, 2 and a half feet of water draught, smaller boats really bounce around in the wash of ferries etc but this just bobs a bit.

I would guess that it's a Danfoss/Secop being Inlander. The Chinese clones tend to be fitted to a fridge designed as 12v from the ground up, but I've seen a couple of conversions, I'm not sure who did them though. The condensers in the side panels tend to be less efficient I think, but that's not based off any tests, just a feeling! You need to leave plenty of space for air to circulate on both sides, a lot of the time they're jammed into a space tight, or there's stuff stored down the side. I'm not sure why the move has been away from having the coils on the back, maybe to avoid damage during shipping and installation?

This is a mass market 240v fridge that's had its 240v compressor replaced by a 12v one. Inlander usually use Danfoss or Secop ones which are very good, but I have seen some conversions with Chinese clones of the Secop BD35. They seem to be pretty good, a bit louder and the inrush current is a bit higher than the newer soft-start controllers Danfoss/Secop are using though. The one thing to note about this fridge in particular, and other similar ones, is that the condenser is built into the side panels rather than on the back like it used to be, looking like a black radiator. You need to leave a good inch or two between the sides of the fridge and the cabinet it's in, so air can circulate. Fitting it tight into a cabinet will cause issues.

The bit from 1/4 mile above Denham up to Harefield Marina is very shallow near the banks, even a V bottomed GRP cruiser would struggle to moor - it hasn't been dredged in many years I think. West Drayton is usually fairly busy when I've passed, but the bit by the Tescos has benches which people sit and drink on at night which can be loud. Once you pass the station on the right, it's the same issue with the water depth next to the bank, much of it is too shallow. Limehouse Cut is pretty unpleasant to moor on - there used to be a lot of break ins around there, and the canal is full of weed. The Bow Back Waters loop around the stadium is fun though, you can't moor there or you get shouted at very quickly and in summer it's weedy. I have a relatively shallow drafted Liverpool boat which seems to cope fine with the weed, go through slowly and it's all ok. I've heard that deeper drafted boats like the working fuel delivery Woolwichs etc have real issues though.

Thanks, I'm on a subscription, and it renewed only a couple of months ago. Who are you using instead?

I've used Boatmail for my post for the last 4 years or so. However, they don't seem to have forwarded any post which I requested just over a week ago, and aren't responding to email or phone calls. Website is still up though. Has anyone heard on the grapevine if something's happened to them? They always reply quickly and send an email well ahead of time if they're going away on holiday etc, so it's a bit odd. I'm aware that it's only one person who effectively does everything though! Is anyone else also using Boatmail and experienced the same thing?

Not sure about this. I have a little 18’ seagoing boat which is currently on the hard standing in a marina. Earlier this year, 8 GRP boats were completely consumed by a fire, which was only stopped from continuing up the line by a steel shipping container. The fire brigade fought it for hours, and in their own words, once a GRP hull catches, it’s very difficult to put it out. I think I’d believe them over someone on the internet telling me that fibreglass is fire retardant. There’s also plenty of GRP boat fires which result in the hull being consumed by fire down to the waterline. The glass fibre may not burn, but the resin does, quite happily!

Yep, those are the 90 degree version I mentioned. Seen a few on boats with either the remains of a plug inside them, or with the housing cracked, presumably because the cable's been pulled - the length of the connector offers a good amount of leverage. The 5 amp 3 pin BS546 plug is better in most regards - it sits fairly flush with the wall and pulling on the cable is unlikely to damage the connector or socket. There are also BS546 amp plugs available with 20mm internal fuses, allowing you to run thick cable to each socket and then use a smaller cable from plug to appliance.

Are you heading south on the GU? Try Matt Miller at Bulls Bridge Dry Dock near Southall. He doesn't travel but there's plenty of mooring nearby, just don't leave your boat unattended for long as there's a lot of break ins around there.

Projector lenses are specified as a 'throw ratio', but the :1 bit is usually missed out. For example, a 1:1 lens means for a 1m wide image, the projector needs to be 1m away. A projector with a 2:1 lens will need to be 2m away for a 1m wide image. Zoom lenses are given as a range - for example 2.0-3.2:1. However, once you get below 1:1, you tend to get issues with fisheye distortion of the image. The lens also becomes a lot more expensive as you need a bigger chunk of glass. Something like this Benq has a 1.21:1 ratio, so mounting it on the wall of your average narrowboat and shooting across the boat to a screen on the other side (about 1.4m I reckon!), you'd get a 1.2m wide image. You can improve the brightness by using a projection screen or paint with 'gain', rather than a plain white wall. For example, Rosco's screen paint has a gain of 1.20, meaning compared to a matt white wall, it'll reflect 1.2 times more light. It's all a bit hazy with gain numbers for paint though, as it's relative.

Problem I find with the Hella DIN connectors is that they stick out from the socket quite a lot. Fine for cars etc where people don't walk past, but on narrowboats things are often a little cramped so you need to be careful with placement. If fitted where someone may knock it as they pass, the end easily breaks off and gets stuck in the socket. There are variants where the socket is at 90 degrees so the connector is parallel to the wall though.

Yep, the Sony standard in broadcast is the one that's commonly followed - pin 1 negative, pin 4 +12v. From memory, the Neutrik NC series XLRs are rated at 10a for the 4 pin and 16a for the 3 pin which is indeed a significant difference. On narrowboats however, 10a is enough for most things you'd want to use - TVs etc. As above, the 3 pin Neutrik NC XLRs are rated at 16a per pin. They're not used for power in broadcast though, as the 3 pin XLR is already used for line level audio signal, and a lot of things need both 12v DC and audio!

These are handy for powering low power 12v stuff like routers, air purifiers etc in boats. Most people have USB-C sockets fitted now, and the advantage of these cables is that you can also use a power bank to use the device elsewhere. You can buy them in different variants which output 5v-12v stabilised, some up to 20v with a suitable USB-C socket. No DC-DC conversion happens in the cable - thanks to the magic of USB-C, the cable requests the voltage and the source does the conversion and supplies it. https://www.amazon.co.uk/Xiatiaosann-Charging-Outdoor-Converter-Adapters/dp/B0CP9B12ZY The 4 pin XLR variant is the de facto standard amongst professional grade camera and grip equipment for 12v power. I've seen this used up to 10a with no issues.

Easier to clean than a built-in plastic tank though, which assume rarely gets properly cleaned apart from perhaps a sterilising tablet occasionally.

There are also lots of permanent online (canal-side) CRT moorings on the canal system, many of which do not have shore power or water. I'd imagine that a water filtration system is rather convenient for this, as you can purchase drinking water and then shower with the filtered stuff. Avoids having to move off your mooring to a water point and back every week or two. There is no average boater though, unless you want to end up with the image of someone who doesn't actually exist. People use their boats in lots of different ways; some for leisure during summer, living on land and keeping the boat in a marina, some live on the boat in a marina full time, some live on the boat in a marina for some of the year, others might live on land and cruise all summer...others still might cruise year round and live on the boat. Or a combination of all those things!

Watts in RF terms can be measured in different ways due to how it’s basically alternating current…in the air. It’s averaged over a time period, or in the case of mains AC where the amplitude is constant, it’s the root mean squared. The peak to peak voltage of mains power is something like 330v. With phone RF, the max 250mw measurement is averaged over quite a long time - 6 minutes by EU standards! You therefore have short term high power peaks which far exceed 250mw (3000mw from what I remember), and periods of less than 250mw. Ah got you, am replying on my phone and didn’t read the whole thread fully. Oops.

This is exactly what I do too, it works very well! Electric cooking throughout summer to make the most of the free electricity, then when the solar drops off the induction hob, electric kettle and air fryer goes into storage and I use the gas hob. Just using gas for water heating, a 13kg cylinder lasts for 6-8 months. kWh is a much better way of measuring energy than Ah. Victron use it for solar yield prediction on VRM, MPPTs use it for yields in the logs and it’s the preferred unit for domestic things. Makes it much easier to compare energy usage, and with more and more boats having 24v or 48v domestic batteries, it avoids confusion and having to convert Ah to compare.

I’m not sure about this - seen a few drive plate failures, including my own; if the splines shear it makes an awful whine but the output shaft still rotates. If the elastomer damper fails there’s a metal-on-metal limp home mode on R&D plates. If this is ignored, the captive studs bang against each other into drive but eventually wear so only a bit of power is transferred and the output shaft lazily rotates.

Great, that link works nicely. My diagnosis would be the drive plate has failed, given the rattling noises and intermittent movement. The gearbox needs to come out to change it, which doesn’t look like too awful a job given the decent access in your engine bay, and the length of the propshaft. Parts are around £100-200 depending on your engine and gearbox, but you can’t order the new plate until you know what bolt pattern and spline count you have - the old one needs to be inspected first.

Can you record a short video with sound? Get someone to aim the camera at the gearbox and coupling whilst you move the engine control lever. Engine on, boat tied up, put it in forward gear, increase revs, then neutral, then reverse gear and increase revs. Finally, increase the revs with the gearbox in neutral. Upload the video clip to somewhere like imgur.com and post the link here as the forum doesn’t do video.

In my opinion, a better way to test for a high resistance connection under load is to use a voltmeter - one probe on the battery positive post, the other on the positive stud on the starter, then try and start it. Then do the same for the negative - one probe on battery negative post, one on the starter casing. Should see no more than 1-2 volts on the meter.

Where are you measuring the 9v? Multimeter directly on the battery terminals or a gauge on the dashboard? If it’s a gauge, try a multimeter direct. If it doesn’t read 9v too, you’ve got a voltage drop issue between battery and engine.