openspaceman

...and the PI just offsets their cost should you choose to sue for the negligent advice in the unlikely case you can prove it.

This is unlikely in english elm as there is no genetic diversity, all trees are the same clone. Mind there seems to be different english elms as 2002 in Boston (Mass not Lincs) Common (it's not a common) there were trees labelled Ulmus Procera leaves of which which weren't similar to those here.

Me too for short sight but I found I needed reading glasses as well at about 50. Now in good light I can pass the driving test without glasses but need something a bit stronger than reading glasses for close in work.

Have you weighed it? How much fuel? Were you in the cab and was it carrying a spare wheel or truck top? In seven years of working with a fleet of 50 vehicles, half of which were non car-derived commercials, none were stopped for exceeding 50 on single carriageways (or 40 as was the rule) or 60 on dual carriageway. By far the most frequent offence was exceeding 50 in roadworks on a motorway. As I have not heard of anyone found guilty of this offence and you can only find this out if a court report appears in a paper (the police are excused answering questions about speeding offences under FOI requests) my guess is that if you are caught for a higher speeding offence e.g. exceeding 70 on a dual carriageway then you get a more severe penalty than doing the same in a car. Since following the DPV thread on here I have been taking note of commercial vehicle speeds and can say on single carriageways most small commercial vehicles keep up with the traffic if it's a major road and that's mostly between 50 and just under 60mph.

I started at the tail end of the elm disease, so there were a lot of long dead elms to fell for a few years. The thing was the elm retained a lot of their strength, the fibres were strong and hinges worked well. Also branches seldom shed during felling. I feel ash will be a very different kettle of fish as it will have deteriorated well before the decision to fell. The fibres will fail short and the hinge won't stand wedges (and the vibration from hammering them may well cause branches to shed).

You mean he farmed the new piece of land? Yes it looks like someone was a bit economical with what they conveyed.

Never needed to change one on a transit but it's straightforward on most engines as long as you note the timing marks and/or lock the gears from moving. The tensioning is usually a matter of releasing a bolt on a idle pulley which is spring loaded, the spring sets the tension and then you tighten the bolt again. We did have one snap at 100k miles (we think the driver was joining the motorway flat out in 4th and slipped it into 3rd instead of 5th). Once the chain isn't controlling the valves some of them are open and get smacked by the pistons. Parts for the repair exceed the cost of a new engine from Ford (£2000 a couple of years ago) even though there was no distinguishable bore or bearing wear.

Most of all never hit an axe with a hammer, it can cause the eye to split out but grind mushroomed bits off before they fly off.

Grind off the mushrooms or use a gas axe to do it When I started work it was with a couple of 65 year old veterans who worked together during the war, when felling was a reserved occupation. Fred was the feller and Ted the assistant, Ted only had one eye as a bit had come off a felling wedge and hit the other one. Similarly my late mate on the same firm lost the use of his eye from a wedge splinter within the last 10 years

Well as you know I'm a fan of super capacitors and my brother, a carbon scientist, talks of ultra capacitors made of plates of graphene that will offer astonishing energy densities but as yet no one can produce a sheet of graphene bigger than a box of matches and they will need km2 sheets. Also super capacitors are very voltage limited so the array would need lots of them. What I don't know is how much start up current is required, I used to help out on a Stenner 72" bandsaw which ran off the diesel engine from a U boat and that seemed to take ages to switch from star to delta. Presumably the 6 times inrush current to run current decays fairly linearly as the motor gains speed so if it takes 10 seconds that's an average of 3 times the run current for 10 seconds. so your 20kW motor at 380V will need an average extra 100 amps for 10 seconds. That looks like 0.1kWh so may well already be possible with super capacitors.

This is sort of what I was suggesting on the Tesla powerbank thread, the battery-inverter could provide 5kW of extra start up capacity and then the optimum sized diesel provide the running power. The difference in price between a 10kVA genset and a 3kVA one justifying the powerbank cost. Problem is it isn't currently stand alone.

On a related note, a primary school friend used to help his father after school cutting kindling from orange crates, by hand, they had a small lever device which the stiks were laid in and then compressed so they could be banded with string or wire at both ends and sold as pimps. His sister burned the device when she moved into the family home but I recovered the metalwork from the ashes and I think he still has it.

Pete is right but the D&A test is only part of the medical, they test hearing, as you have to be able to hear warnings, sight, particularly colour blindness to red and green and general health, blood pressure, balance, touch toes (I never could) etc. As Pete implies I can see no advantage in getting the PTS competency unless you have a job offer, in which case the company will be your primary sponsor and organise the courses and medical. In my old company it wasn't unusual to have to repay the training expenses you left within a given period, I was never sure how this stood with employment laws.

700C is very hot for a steel walled retort because at that temperature the steel will oxidise on the outside at least. Most of the mass loss is in the temperature range 330C to <500C above 800C the char is almost pure carbon and only 15% of the dry weight of wood used, depending on species. Batch retorts (i.e. those that you initially heat with other means and then they burn their own offgas to sustain the temperature) have given off most of the gaseous pyrolysis products by ~450 C so there is no more fuel to sustain the pyrolysls, as above about 460C the char undergoes a change which requires energy input it tends to not exceed this temperature in the absence of other heat input. This lower temperature char thus still contains some tars which need to be burnt in a flame else they smoke which makes it poor for indoor cooking (indoor use of charcoal is unwise because of the risk of CO but it happens in many less developed urban areas where a wood fire and associated smoke en mass is unacceptable) . From the little I have seen of imported hardwood charcoal it typically is much denser than ours and made at higher temperature, so it is harder to light, burns more slowly and gives off little or no smoke. Incidentally it is the fat dripping onto the hot coals, being partially burnt and then condensing on the food that makes flame grilled meat a source of VOCs and free radicals which are best not eaten regularly.

Hotter drives off more volatiles and increases the fixed carbon content. So hotter means less yield but higher carbon content. Carbon has a higher calorific content per kg than wood. Retorts tend to self limit their temperature because the process goes back to endothermic above about 440C as the structure of the char matrix begins to change and most of the evolution of the hydrogen and oxygen containing species has finished so the exothermic reactions of the initial pyrolysis products splitting and cracking has finished. Char from the centre of a traditional burn is subject to higher temperatures as it is in direct contact with the combustion process. I'm not sure where most imports come from but in those urban areas in countries that still depend on charcoal for cooking our sort of easy lighting , flaming barbecue charcoal is not acceptable because flames mean lots of volatiles still present, so they want denser harder charcoal that burns with a flameless, smokeless heat.

Fairy Nuff but that's on your own land not FC or NT and not working for a firm with civils and domestic clients. I was much the same for the first 20 years and then NPTC came along with chainsaw unit 16 on, 1991 I think, there was no question even then that it would be a licence to work. Mind I still work with a chap of a bit younger age than me that has his old blue book but never registered the assessments. Mind I've never had to present anything other than CSCS card I wonder if your handwriting is as bad as mine ;-)

We know thefts like these are a low priority ( a nephew and an old girlfriend's lodger have both recently joined the police and both are inundated with sexual offences which take all their time) so it's unlikely any serial numbers will be put on a police report or database so a crowd sourced database that is accessible has a value for lay persons to check. As I understand it the vast majority of people will not steal, a smaller majority will not buy stolen goods. Hence it is desirable to have a large corpus of stolen goods and then persuade people who are offered machines to check and not buy equipment where the numbers have been defaced. In the 7 years I worked for a company we had numerous saws and strimmers stolen from vans and two tracked chippers stolen. Only one tracked chipper was found, by coincidence only, and that had been bought by an innocent contractor. Had he been able and willing to check its provenance I'm sure he wouldn't have been defrauded. It's a fair point that it's time consuming for a large company to upload lists of machines but the database costs money to run and if its no being used, as Steve has said, then there is no incentive to improve it. Similarly it becomes arduous to load lists of recovered numbers or descriptions, what would be required would be some fuzzy logic (like Googles search engine) which would scan reports or a dealers job sheets and automagically do a comparison. So do JCB if you phone up for spares but there is no explanation whether they actively cross reference it.

Sounds a sure way to seize a saw. With the throttle closed it will only getting petroil through the idle jet, so max revs and min lubrication. As an aside it's why you never coasted Ariel Leaders down hill and why 2t Saabs had a free-wheeling clutch.

You still get top marks for trying

What I didn't mention is that as the solar charger power is smaller than your pump requirement even in full sunshine it means the pump will be switched on and off by the under voltage feature of the charger. Now this may not matter to you but it will mean the battery is constantly cycled from around the low charge voltage, 11.5V ish and the state of chrge when the solar charger cuts back in, this could mean the battery charge discharge cycles will shorten its life.

Yes but it's worth reading about how a three stage conttroller enables the batterry charge rate to be optimised and as Daniel says this is simple and the battery can be tiny or simply a large capacitor. https://www.powerstream.com/pv-control.htm Same $ price as our £ price Yes this is how we did it in the old commutator days, the current increase as the back emf drops as the motor slows down, this is why there is a large inrush current as the motor starts. My guess is the modern brushless stuff has built in under-speed protection. It will be interesting to have an ammeter in circuit to see how the current behaves as the voltage drops. It won't but if you size your panel to produce sufficient Volts when it's cloudy then it may produce too high a voltage when sunny and therefore a higher current. In your case it may well be that if the pump motor is protected and the motor runs for long enough in bright sunshine you need nothing else. Yes simple is best but the leisure battery can be small, say a 17Ahr golf cart type. As Daniel says the charge controller could handle the battery protection too. I'd still consider swapping the battery for a large capacitor. I still tinker, am making a headlight on buzzer when the ignition is off as I keep flattening the battery on an old car, just a buzzer and diode circuit.

It's difficult to decide, for a start we don't know how much bright sunshine Marcus has. I do know in my latitude that over a year each Watt of installed PV capacity will generate 0.75kWh over a year and 80% of that will be from May to September. This is no problem as he only wants top irrigate in summer. Marcus's tank is about 3000litres and at 6metre head his pump will deliver 8 litres/min. So IF he supplies 12V to the pump it can empty the tank in about 6 hours. The average solar energy received is about 4kWh/day per square metre in summer so it's only about sizing. First the thing about super capacitors is that they mustn’t be overcharged. Given that a solar panel only delivers a fraction of the voltage when shaded by cloud compared with in full sunlight this means the charge voltage from it will vary greatly. Also as super capacitors are rated at about 2.6V you need 6 of them in series and a means of making sure each one only receives <2.6V. This normally means having an equalising circuit around each capacitor. Ones sold in packs for boost starting a car will have this built in. The quandary is should you have a 12V 54W panel that only works in full sunshine, in which case you can connect the pump directly to the panel and have the pump stalled when the voltage is too low to run it or should you have a 20 or 30V panel and higher power and then control the output. If you already have the panel I would just try this first. I have been given one of those panels that you stick inside a car windscreen when parked up, charging via an always live cigar lighter socket, it seems to use most of its power flashing a built in diode I think I would opt for the 12V panel a germanium diode then the super capacitor pack and a simple circuit using a Zener diode to trigger a transistor and switch the pump via a latching relay. Then when the pack is above 12V in bright sunshine the pump runs constantly. If the panel is shaded then it still trickle charges the super capacitor until it reaches 12V, then the zener triggers the relay and the pump runs on the energy stored in the super capacitor until the voltage drops. These super capacitors are hundreds of Farads and will run the pump for minutes whereas the bass booster capacitors in car audio systems are 1 or 2 Farad and will only run the pump in 1 or 2 second bursts. You could just use the type of controller https://www.water-garden.co.uk/prod/solar-charge-controller-10-amp and simply have the capacitor where the battery should be

Yes I see what you mean now, the battery guard protects the battery from being too deeply discharged, in doing so it means that the pump will always get enough voltage to run rather than just sitting there humming. It will be interesting to see how it manages.

It's the battery that it safeguards Remember the battery charging takes some of the power, which in marginal sunshine is why a capacitor may be better. I imagine it just uses a MOSFET to cut the current, the panel then is simply open circuit and the heat is dissapated in the panel instead of the current taking energy out. That pump has 8l/min output at 7 metre head. At full flow it requires 54W=4.5A and 12V. I wonder if it would be cheaper to find the 12V pump out of a Toyota prius, as the impeller has permanent magnets and the coils that give a brushless rotating field are sealed, I've no idea what head it will pump.

Probably not I doubt even 35V would break down the insulation in the 12V pump coil but over current could easily do damage. You have to consider the internal resistance of the panel also so if that is high relative to the coils of the spinning motor (because of back emf the motor will draw less current when spinning than when stalled) the open circuit voltage will drop away. If you have the super capacitor in circuit it will store charge until there is enough to run the motor in a spurt. Once the voltage drops to below that necessary to keep the motor running it cuts off and the panel then charges the capacitor back up. It serves the same purpose of a battery but without the problems but unlike a battery which stabilises its own voltage to an extent it does need some control. You can do it with a resistor and Zener diode but that wastes power, so if and only if the panel can produce more current than the motor can stand a relay and current limiter is the way to go. I'm sorry I'm not clever enough to deliver a design off the top of my head. If a resistor is necessary then a light bulb may be better as this has a decreasing resistance as the current drops. I see Difflock has posted a kit with built in current limiter.