Member postings for Paul Kemp

Telegraph article to me was a bit speculative with references to MP's warning the Government and a historic quote from the boss of National Grid without an up to date quote or definitive references to back it up. Never the less from discussions I have had with UKP there is underlying truth. I do find it a bit of a worry though that "MP's are warning the Government" at this stage of the game! Surely Government is made up of MP's and they take decisions based on "advice". You have to question where the advice came from? Policy is set, the course charted with target dates so it's a bit late now to be posing a fundamental question such as how will all this power be distributed to point of use? Smart meters will undoubtably save us - or will they? Are they capable of limiting current on an external signal, outside interrupting it completely? Will we end up with load shedding consumer units? Are existing EV's equipped to communicate with the Grid to switch on or off or increase / decrease current draw for charge on command form the power supplier? Taking power from EV's to back feed the load is all very well but how will they know if you are intending to drive off at 04.00 just after they have drained your battery and assuming they had a good 5 hrs to put it back! That is without the increased discharge / charge cycles at the power company convenience reducing the life of the battery you paid for! I think there is a song about this........

Finally the easiest way to cripple a country now or into the future is to knock out the wireless connectivity and networks. With even your washing machine wifi capable you won't even be able to wash your socks, assuming the lights stay on!

Paul.

My arbor for the Omnimill has a keyway, never use it. As Dave says just horse up the nut. Less chance of doing some spectacular damage without a key if it all goes wrong. I have never knowingly had a cutter slip without a key. Word of warning though - don't try any ambitious climb milling with a slab cutter - unless you want to test your work holding to the limit / see how past you can project the job across the shed!

Paul.

Stuart is correct on both counts from my experience. From recent discussions with our local DNO for a high capacity 3 ph supply their stand was the cable and sub station costs would be wholly to us. When asked if someone later wanted to tap into that supply what would happen, we were told in that circumstance the new customer would be charged a proportion of the fee for the supply we had paid for and we would then be refunded a proportion of that cost. The question was more from the perspective of preserving the capacity we were paying for than recovering cost so we didn't follow up on what proportion or if there was a time limit. Believe me the costs are not insignificant for either the cable - charged per metre including ground work or the sub station. Out of curiosity I asked about the situation with domestic supplies living in an area where the houses are a century old and the answer was in line with Stuart's point that without load balancing (rationing) through smart meters the main cables would need to be uprated. It can be done, it just a costs and someone has to pay - you can guess who the someone is.

Paul.

Contrary to claim above actually h2 tanks do not need to be heavy, luxfer already make lightweight tanks used in hydrogen fuel storage. The video makes some very important points not least the capital cost aspect of electric v h2. Currently running cost for h2 is higher and never likely to come down to meet MGO prices but it is likely to meet derv in the next few years. Plenty of opportunity for h2 production, there are plans approved to site an electrolyser on a solar farm near me and it complements solar and wind energy nicely by providing a means of energy storage to iron out the intermittent nature of solar and wind without tons of batteries. There is a lot going on in the h2 arena currently and it shouldn't be ignored.

Paul.

I am intrigued to think about how car parks will look by 2030 and beyond, or even if they will be required - assumes the masses will actually be able to afford to have / use a vehicle. I currently park at the 02 in London when I have to travel to the office. Car Park 1 has a small charging station on one edge. Originally from memory (not that I really took note) there were probably 4 posts with EV sockets. I notice since the plague the area has been revamped with now probably six new charging points of which four I think are 'fast Chargers' and 2 slow. Where originally the posts were small blue affairs the new outlets are more sophisticated probably about the size of a petrol pump, there is new screens and notices limiting the amount of time you are allowed to park and charge (I think it's 2 hrs but it may be longer - again I have never taken that much notice!). The new charge point seems to be some kind of franchise operation with a coffee bar round the back. One notable difference is with the old posts (where I don't think there was a time limit) every post seemed to be occupied every time I passed by. Now with the new set up I don't think I have ever seen more than one vehicle hooked up at a time. I wonder is this because the cost to use them is vastly different or is the time restriction unmanageable? I guess if you go to a show or have gone to work the last thing you want to be doing is watch the time and break off to go and move your car? Maybe the EV owners are all isolating? Maybe for venues and work places intervals and coffee breaks will be replaced by move your car breaks?

I guess as EV use expands the ideal would be to have a post at every bay? Having a rough idea of the grid distribution in London and guessing the car park probably holds 1500 vehicles if every charger were 7kWh or more we are talking a pretty hefty addition to power requirements in the area.

From my marine work where we are talking tons of batteries providing 500kWh or more the charging requirements require dedicated 7kva supplies for some scenarios 11kva, things get very interesting in securing available supply and the costs eye watering.

Lastly talking to some industry experts there is a lot of doubt that the price of electricity will drop as the investment for renewables not only in construction but in running costs is high and the investment to improve distribution massive.

Intersting times.

Paul.

Apologies, so you did, brain playing tricks! 14.7p is somewhere around the national average so not so excessive. Yes it was Octopus he was talking about at 4p but I guess that could be anything up to 4.9! But you also have to factor in the increased standing charge to get that. Unless they program washing machine etc to run in the same period so a lifestyle and habit change to shift more than the vehicle charging to the cheap window the real cost is still more than 4 / 5p if considering only the vehicle. No doubt after an evaluation period he will have some numbers to support but with an average daily mileage Mon - Fri of around 80 with a maximum of half that on electric, without a long break for a charge somewhere he will still do the other half on petrol, it will be interesting to see how it pans out.

Paul.

PGK, 3.2 kW is a little over 13a on a 240v supply in basic terms so would be pushing a 13a socket to the limit. The charger has already been installed in readiness and the installer ran a dedicated 32a supply (single phase) which should just about support 7.4kW. Note however the comment the vehicle is only rated to take 3.2kW so the higher power charge would be pointless. Your 18p/kWh is pretty heavy,that's around 3p above the national average! Personally I would question the design of the vehicle in being a plug in hybrid with only 40 miles range on electric and limited to that charge rate. To me producing as a self charging hybrid would have made far more sense but not such a big tick in the green box. Choice of vehicle was governed by employer conditions and capital cost, an alternative would have cost a significant employee contribution per month which would definitely have vastly increased his personal costs.

Paul.

Try asking your power supplier to upgrade your supply and see how much they quote you! BIL has just had a green car imposed on him by his employer, house has 100a incoming, on that he was limited to a 3.2kW charger (will take between 4 and 5 hrs to charge the vehicle), it's a plug in hybrid and has a range of 40m tops on electric including on the run top up from regen brakes. Car not rated to use fast chargers in any case so had he been able to have a larger one at home the vehicle won't take it and no opportunity for a fast top up at the supermarket or other fast charging station. Cheapest energy deal he found is 4p / kWh between midnight and four am. However to get that the standing charge is significantly higher (he didn't share how much or I wasn't listening) he has evaluated the costs between his old and the new vehicle. Sure he will make a saving in fuel if he can get a full charge at 4p / kWh (which isn't exactly that as you have to factor in the higher standing charge and he can't get it long enough for a full charge) but at average domestic electricity prices and if he had to factor in costs of ownership such as eventual battery replacement it doesn't look so rosy! One question, with all the cheap renewable energy now out there has anyone seen their electricity bill decrease year on year unless you are making your own?

Paul.

SOD's perception of free energy for the taking is not quite there. I have been involved in a project to green up marine transportation for the last two years. Yes there is technology available however it is not equivalent to diesel in terms of asset utilisation or in capital cost and the vast savings predicted in running costs are not coming through either when considered over the life of the equipment. Battery prices have come down proportionate to performance coming up but most of the big battery manufacturers I have spoken too agree this has reached equilibrium and won't change significantly now until solid state batteries are perfected and marketed potentially still 10 years off (their words not mine)

Power supplies where they are needed are also not there, massive capital cost to extend them to POU. You can argue that can be written down over many years but the cost of power is also important when compared to existing fuels. The change to green needs huge investment and that cost is going to filter down to you and me like it or not. Investors only invest to make returns!

There is a lot of smoke and mirrors in the energy business, none of this is going to be anywhere close to free!

Paul.

I would be careful using a 'normal' pallet company to do the job, have you not read the tale of woe of the chap on here that bought a Colchester lathe that was dropped? Check insurance very carefully as they were comments on there, later shown to be true, that insurance value of a std pallet load is quite low per kg. Entirely possible in your case it will not even cover what you paid! If you want to do it on the cheap then it's likely to end in tears! When I collected my Omnimill I borrowed a plant trailer, took a mate and some gear, 3 1/2 hr drive, extracted from shed and loaded and 3 1/2 hr drive back, was home in time for tea! All under my control and at my risk and convenience.

Paul.

I would say about the only useful information from a copper boiler drawing if you want to make a steel one is the overall sizes, barrel diameter, overall length, width and height. 2 completely different materials with completely different properties.

Paul.

Some interesting views here both for and against. One contributor states you make your own plug with soft solder and a rivet (a practice historically advocated by various ME "guru's). The American boiler code quoted by another requires pure tin - sensible standard depending on the pressure of the boiler. Tin melts at around 232dgrees C. Temperature of saturated steam is around 177 degrees C at 100psi, so on a boiler of WP pressure of 100psi or less you have a reasonable margin although the tin probably will not need to fully melt in order for the plug to fail so it may relieve at a lower temperature than the actual melting point of tin! If you use pure lead with a meting point of around 328 degrees C you have a better margin for service and unwanted false alarms but the strength of copper decreases to around 95% at 100 degrees and further decreases to around 90% at 300 degrees (graphs on interweb I consulted have poor definition so very course values). If you alloy tin and lead the melting temperature can in fact be increased above the constituents which makes it worse! So if you are making your own plugs you need to very sure of the soft solder you are using to end up with a product that delivers the required protection and does not give a false sense of security!

Then we have the maintenance aspect. The plug itself as also mentioned in this thread needs to be removed, inspected and cleaned on at least an annual basis, on full size loco's they are inspected at every wash out (interval between 14 and 30 days steaming). If a layer of scale deposits on the water side of the plug this will reduce the heat conduction away from it and lead to premature melting, the scale can also block the passage left by the melted material and stop the discharge!

It was mentioned an accident resulted from a dropped plug through fire being blown out of the door! To paraphrase a famous film "it's not supposed to blow the bloody doors off". Clearly in that case the bore of the plug was far too large. The purpose of the plug is to give a warning it is not supposed to act as a safety valve to dump the boiler pressure into the fire!

Summary fusible plugs are no substitute for proper boiler management! They are difficult to make and size to be effective. If not regularly maintained they can be unreliable. In anything less than a large 4" scale TE or larger 7 1/4" loco boiler they are unlikely to be of any real practical benefit. A safety device you cannot rely on is not worth having.

I have previously tried to find reliable documented accounts of small boiler failures per se let alone failures due to low water level and found nothing. There is a good ORR report on a narrow gauge loco the driver of which was inexperienced and if I am thinking of the right one managed to continue to run the boiler for a time with a dropped plug and completely wrecked the boiler, plug didn't save anything there! So back to the previous point, manage your boiler competently if you want to prevent damage! Definitely don't rely on something cobbled together in your shed with unknown or unverified materials!

Paul.

Can anyone reference the "recently added requirement" for CE marking? I can think of a few reasons why there is not much point in a 5" gauge boiler. One being where would you get a plug of known composition / quality in that size that you would be confident of fusing? Do those of you that have them fitted remove them on an annual basis for inspection? If you drop a plug you are supposed to have a re-inspection of the boiler. I suspect the requirement has been added by the certifying body that underpins the CE process rather than any actual change in standards but happy to be proved wrong.

Paul.

The Goodyear airship was plodding round the skies of Kent around Ashford yesterday.

Paul.

Nice to see some common sense on stay spacing there Robin instead of the usual hysteria! As Jason said steel for the 3" for the OP makes far more sense than copper.

Paul.

I would second Jason's suggestion of TT, there is a strong miniature prescence on there. On the boiler (assuming it is a larger one and steel?) you could also try Holt boilers, now run by a Mr Kirk I believe, I know nothing about them apart from seeing them mentioned a few times. There are a couple of other options too if you dig around a bit. Normal wait for a boiler from order to delivery these days seems to be in the region of 18m to 2 years. As mentioned by others though there is plenty to do in the meantime. I would caution completing the tender before you have a boiler as boiler making is not a precision activity generally and you don't want your tender being too wide / narrow to marry up! Wheels are probably a good place to start, plenty of work in them! If you can stick at making the wheels you have a fair chance of completing the rest! Plenty of half started engines out there where people lost interest part way through! I started my current build end of 2016 and it's not there yet!

Paul.

My next workshop if I ever get to build one will have a post crane, you can always put a strut under the end to increase capacity if you make the beam strong enough. Really handy for moving heavy vices, dividing heads and heavy jobs on and off machines. If you are building a new workshop worth thinking about some lifting arrangements from the off.

Paul.

Vic,

As far as I know from the last time I spoke to Ian there has never been trace of it found. In that case being such an individual model I would agree it was a professional job and probably filched for a private collector. I very much doubt it was taken for scrap. I wouldn't be surprised if in years to come it re-appears somewhere beyond our shores!

In the case of the loco from other info on the web it would seem it was presented to an antique dealer about 30 miles away from where it was stolen, said dealer declined to buy it but told the fellow it was worth more than he was asking for it.......!! It has also been said elsewhere that the car has been traced to its previous keeper only who sold it for cash some weeks back to "travellers". Needless to say they did not register new keeper details!

I would say the above suggests it was opportunist as if stolen to order they wouldn't be moving it on at a high street antique shop. Considering the vehicle I would guess the boys in blue would be pretty certain who was involved and there is a high probability they live currently somewhere in the area. However with no means of proof this will remain unsolved and with publicity both items will be subjected to an angle grinder and turn up at the local scrap yard. The law sadly only works against those that abide by it!

You never know who is looking at what you have! There are plenty of people only to happy to take it away from you even if they only get a fraction of its value! Sad thing is a lot of these things have a value greater than money.

Paul.

Duncan, not quite sure I follow on exhaust clearance reducing cylinder power? I guess that might happen if you have zero lap on the admission side but the clearance on the exhaust also relates to the port spacing? Admission "clearance" could be considered to be introduced by the effect of introducing lead (inlet opens before dead centre)? Exhaust clearance only introduces a small difference in actual valve events and at the point the exhaust opens the majority of the expansive effort on the inlet steam would mainly be spent? At high speeds it is just as important to get the expanded or "dead" steam out as getting fresh steam in? Clearance surely also give the effect of keeping the exhaust open longer reducing the resistance on the other side of the piston? Is your 25% / 75% relationship true if you consider at 25% cut off valve travel is consequently reduced so would closing the inlet early necessarily result in the same proportion of opening exhaust early? In full gear (say 80% cut off) would exhaust open at 20% stroke? If you look at an indicator diagram that situation gives zero expansive effort at full gear or 25% cut off? Been a long day so I am probably missing something!

Paul.

Agreed that may be an influence, smacks of paranoia though? The same regulations apply to all, it's how you mitigate the risks and discharge your duty of care without losing business that is the balance? There are ways of managing these situations through freindly assistance instead of a heavy handed H&S gestapo approach.

Paul.