Ronaldo47
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Posts posted by Ronaldo47
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My understanding is that manufacture and sale of conventional tungsten bulbs for things like spotlights and headlights are not being prohibited and such bulbs should continue to be available. Vehicle spotlights and the like rely on the essentially point source of a compact tungsten filament for their reflective and refractive elements to produce the desired beam shape. It is simply not possible to make a LED that simulates a compact three-dimensional point source. The best approximation is the 'corn-cob" array of elements pointing in all directions, but as such arrays are much bigger than a compact tungsten filament, they are no substitute for tungsten bulbs.
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I well remember seeing dayight through some small holes in the side when we carried out the daily cooling water filter check, which only involved removing the occasional bit of water weed. The filter was secured by two small wing nuts and was below the river level, so you needed to be fairly quick to prevent too much water coming in. Of course on one occasion someone dropped one of the wing nuts, leading to an anxious few minutes until it was retrieved!
.We went at Easter, and did have a couple of days with patches of very heavy rain, but didn't experience any leaks.
We were very satisfied with the boat, and gave the reception a list of our likes and dislikes. I think the only dislike we had was insufficient shelf space for wash bags etc. around the hand basin. A 240V invertor was provided for an electric razor, but none of the men used them. There was also a conventional 3 pin 5A socket for a 12VDC supply, but in those days we had no need to use it for anything.
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51 minutes ago, Boatingbiker said:
Basically, the frictional losses of an elbow is greater than a 90 degree bend which in turn is greater than a pulled large radius bend. For gravity systems to work the resistance of all fittings and the pipework need to be the lowest possible. Pipes need to be installed with a good rise to highest point ideally the radiator to promote flow.
However, we had a boat with a reflect stove as shown, which used 15mm pipework and a circulation pump. Once the pump was stopped the stove would lockout on high temperature. The stove would then need to let cool down over a couple of hours before being relit.
Shouldn't 'greater' be 'less'?
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You need to bear in mind that there are (or at any rate, used to be the last time I needed any) three different grades of copper pipe: Hard; Half-hard, and Fully Annealed. Tables X, Y and Z, but not in that order! The Hard grade has thinner walls (and thus a larger internal diameter), but is not bendable. It is/was cheaper than the half-hard, which is bendable with springs and bending machines. The fully annealed stuff has thicker walls still and is readily bendable by hand and was/is mainly used for cold water mains underground, but I guess has now largely been replaced by plastic. The thin wall stuff used to be significantly cheaper as it contained less copper. I did manage to put gentle bends in two lengths of 28mm thin wall (non-bendable) pipe that I needed for the gravity feed from my gas back boiler to my hot water tank by using a home-made bending block of the type that that old books described as being used by builders for bending pipes in the days when proper pipe benders were expensive. Just a hole somewhat bigger than the pipe, drilled through a piece of fairly thick timber. You secure the wood to something immovable, thread the pipe through the hole, leaving enough out to get a good leverage, and press down firmly. The pipe will bend slightly where it emerges. Pull out the pipe a bit more and repeat. Or perhaps it was push the bent bit through the hole and repeat, it was a long time ago when I last did it. I managed to make enough gentle step-wise bends with some slight crippling of the pipes that was sufficient for my needs and I did use a blow lamp first to soften the pipe at the bend location. The pipes were at the back of a built-in cupboard so appearance was unimportant.
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A 60' hire boat we used in the late 1970s had gravity-fed radiators heated via a gas boiler. As far as I recall, it managed with 22m pipes. Agreed about the slow bends and no sharp right angled bends. Large radius bends for copper pipes seem to be unobtainium in my local builders' merchants now, so you might need to bend pipe yourself. Burrs at the cut ends of pipes should be carefully removed. A gentle progressive gradient should ideally be provided in the flow and return pipes, and dead horizontal runs avoided where possible.
When I designed the central heating system for my own house in the power-cut era of the 1970's, I designed it with gravity circulation in mind so it would be operable (at lower performance) in the absence of mains electricity. At that time there were DIY books available that had information on designing both gravity and pumped systems. 22mm copper worked ok. A lot of the older books discussing gravity systems had flow resistance figures based on iron pipes which, due to their rough interior surfaces, have a higher flow resistance than a copper pipe of the same bore.
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I had wondered what became of Bushnells of Maidenhead. A group of us hired one of their boats in the early 1970's. I recently posted a photo of our boat (Gay Fantasy No. 4) elsewhere on this forum. We did the return trip to Oxford on about 40 gallons of diesel. The boatyard asked if we had filled up en route, which we hadn't: we had simply kept to a steady speed all week as we hadn't been in a hurry.
I remembered I had a 1963 Blakes catalogue (inherited fro a deceased relative), but on digging it out just now I find it only covers the Norfolk Broads.
As a young child in the 1950's I well remember seeing a British Waterways stand at an exhibition in London I went to with my parents. It had displays and brochures showing various hire boats and their interior layouts . It could have been a Radio Show, a DIY exhibition, or an Ideal Home exhibition. I do remember thinking they were expensive, but then at the time we used to spend our holidays at a seaside boarding house at £2/10/-d a week, half board!
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Have you tried the public library, who might be able to get you a copy on loan from the British Library? I did this a couple of decades ago with some Edwardian/late Victorian books on railway signallng and rolling stock. It used to be a free service, but now I think there is a charge.
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3 hours ago, dmr said:
Is that in case a boat got stuck, came back a year later and completely forgot they got stuck before ? 😀
I assumed they must have been hired boats: a privately-owned boat owner ought indeed to have remembered where it couldn't go.
I well remember the joints on a bottom gate of one lock were so loose that the lower part of the gate wasn't fully recessed when the beam was hard over, and the only way to get in when ascending was to run full tilt into the lock under full power to use the boat's momentum to get past the sticky bit, and then apply full reverse to avoid hitting the cill. Going downhill, opening the paddles at the top gate to let some water down helped flush us out past the sticky bit. We were a group of 14 in two boats hired from Anglo-Welsh, and they both had the same problem at that lock.
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I remember that, when we went down the Southern Stratford to the Avon in the late 1970's, there was a notice at one of the locks with a list of about half a dozen boats that were too wide to go through it.
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Boiling a given amount of water in a low power kettle could end up using more energy than boiling the same amount of water in a high power kettle. The lower powered kettle will be loosing heat by convection and radiaton to the surroundings for a longer time than the high power kettle. On the other hand, if the body of the lower power kettle has a lower thermal mass to be heated up, and a smaller surface area, than the higher power kettle, this could compensate for the longer time that heat is being lost by convection and radiation.
Somewhere I still have one of those Pifco heaters you could put into a cup to boil just a cupful of water. Haven't seen them on sale for years, they probably don't meet modern safety regulations.
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Indeed, consulting an atlas shows that even the most southerly point of the UK lies North of the St.Lawrence River, and that freezes over every winter.
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Hydrogen made up a significant proportion of coal gas. Coal gas was supplied at a lower pressure than natural gas and had a lower calorific value, meaning that the supply pipes required for coal gas were significantly larger than those for natural gas. I recall that when I installed my gas back boiler myself in the 1970's just after conversion to natural gas (DIY gas installation was legal then), the installation instructions said that the supply pipe for coal gas had to be 3/4", whereas for natural gas, 1/2" was sufficient.
I guess that gas consisting only of pure hydrogen would need to be supplied at a higher pressure than the old hydrogen-containing coal gas to avoid wholesale installation of larger-diameter pipes in order to supply an equivalent amount of energy, so potential leakage might be more of an issue.
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At least the quadrants are still useable. On my last visit to Stratford-on- Avon a couple of decades ago (on a day trip, not by canal) I noticed that, on the lock gates between the canal basin and the river, the gaps between the bricks of the quadrants had been filled in with cement, level with the tops of the bricks to produce a completely smooth surface. This was no doubt to reduce the trip hazard for the many tourists, at the expense of making life difficult for canal users wishing to operate the lock gates. I did stop and help a boater who was having trouble getting enough purchase to open the gates, and the smooth surface certainly didn't make it easy. There had been no problem with grip when I had been through the lock by boat myself in the 1970's. I don't know what the present situation is.
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Some years ago I needed a replacement glass for my gas boiler. The local heating sypplies merchant said that, due to its age, replacements were no longer available, but sold me a piece of heat-resisting glass bigger than the size I needed and my local glazier cut it down to size for me.
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More than 25 years ago I was tempted into buying a die stock with a 20mm conduit thread die from a second-hand stall in Romford Market for £2. I finally got to use it for the first time a couple of years ago to instal some additional sockets in the flat my son had bought. I don't have a pipe vice, but clamping the conduit in a Workmate and preventing rotation with a Stillson wrench worked OK. I would love to get a conduit bending machine, but they are a bit too expensive to buy new and I haven't seen any at car boot sales yet.
When visiting my late brother-in-law in France, I found that the French have gone their own way with pipe sizes. While we commonly have 10, 15, 22, 28mm, their series is 10, 12, 14, 16, 18, 22, 28 mm. French plumbers do not usually use soft solder with copper pipes, preferring to make brazed joints.
The old German electrical steel screwed conduit thread (Stahl panzer rohre gewinde, abbreviated to "PG") was defined in terms of "Gewinde pro englisher zoll" (threads per english inch), and was supposed to have been superseded by metric sizes a decade or so ago, but there still seem to be plenty of fittings for the old sizes available, even in the UK, for compatibility with imported continental stuff. .
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I first read it in the 1970's in a book I got out of the public library written by a plumber who had been given a scolarship to research the history of pumbing. I have also found references to this in other books on pumbing I have come across. While I trained as an electrical engineer, dad was a pipe fitter, and from an early age I have always taken a keen interest in anything to do with pipes snd plumbing!
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1/4" BSP is 28 tpi, 1/4" NPT is 27 tpi, both are about 0.4" diameter mid-taper. The only pipe sizes where the pitches coincide are 1/2" and 3/4", 14tpi for both standards, but 55° flank angle for BSP and 60 ° for NPT. NPT is used in the USA and countries where US practice is followed, the rest of the world uses BSP.
The discrepancy between the nominal pipe size and the actual diameter goes back to the time when lead pipes were made by wrapping strips of lead sheet around a mandrel and soldering the seam. The nominal size was that of the mandrel, and thus the bore of the pipe, not the external diameter.
Converely, the iron pipes originally used by the fledgling gas industry in the early 19th century were actually the barrels of governent surplus muskets from the Napoleonic wars, which had a 1/2" bore. These were joined using loose iron sockets. Into the gap between pipe and socket was packed a mixture of iron filings and a chemical that would produce rapid rusting and hence expansion of the mixture to produce a permanent gas-tight mechanical joint. A bit like joining modern solvent-weld plastic pipe. Developments in pipe manufacture allowed the production of pipes with thinner walls than musket barrels, and for compatibility with the original pipes and fittings, the new pipes were made with the same external diameter as the musket barrels..This is why the bore of a nominal 1/2" iron pipe is significantly greater than 1/2", and plumbers still refer to iron pipe as "barrel".
Likewise, the nominal sizes of Imperial copper pipes were the internal diameter of the original types that had significantly thicker walls than later types. Hence the original 1/2" copper pipe had an external diameter of slightly greater than 15mm and a bore of 12.5mm, and with the development of thinner wall pipes, the external diameter of the original thick wall type was retained.
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There is a type of latching relay, called a "Carpenter" relay, that changes state with each impulse on a single wire. The duration is not important as long as it is enough to make the relay operate. They are not very common in the UK, but are used extensively in France for lighting installations that need to be controlled from more than two positions: the intermediate switch normally used in the UK is unknown there, where multiple switches for staircases or long corridors are normally spring-biassed push-to-make switches conected to the same terminal of a Carpenter relay.
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When I retired, we treated ourselves to a Mediterranean cruise. On the way back we had sea fog for the entire day and a half it took to sail from from Italy to the Straits of Gibraltar. You could get above the fog and sit in the sun on the 11th deck, but the foghorn accompanyment rather spoilt things.
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A couple of decades ago at Easter we moored up on the Southern Oxford at a towpath that had both shiny Armco piling and a dense growth of overhanging vegetation between the well-used footpath and the towpath edge. Using the woodsaw blade of my Swiss Army knife I cleared away enough vegetation at front and back so we could get on and off easily, and the many saplings thus removed provided bows and arrows, as well as fishing rods, for our young children. It was indeed evidently a wildlife haven, as evidenced by the field mouse stowaway we found a day or so later in the larder, eating its way into a packet of instant mash (and promptly dispatched with a handy tin of baked beans).
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21 minutes ago, Murflynn said:
very bad design, deliberately introducing tripping hazards where you are s'posed to put your size nines. obvs no elfinsafety review was undertaken.
This reminds me that the last time I visited Stratford basin ( a couple of decades ago, and not by boat), I found that only the tops of the usual arc of raised bricks for foot grip at the lock gates leading to the river, were visible, having been embedded in cement to produce a perfectly smooth surface The weather was damp, and lack of grip was presenting a problem for the crew of a boat locking through.
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Thanks very much for the explanation of the ratiionale for the military compass using an unit that is normally confined to scientific and electrical engineering calculations.
When reconstructing liveries from old photographs, you have to bear in mind that the early photographic emulsions were not sensitive to all colours. Thus the early "ordinary" plates were only sensitive to blue, and would render both red and green as black, the later "ortho" plates were sensitive to blue and green and so would render red as black, and the modern "panchromatic" films are sensitive to all colours, although still over-sensitive to blue unless a yellow-green filter is used. Ortho and Pan emulsions only started to be used around the turn of the 20th century, so virtually all Victorian photos would have been taken on "ordindary" film. Pan cost more than the other earlier types, which continued to be available to general-pupose photographers into the mid- 1950's.
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There is an Interpretation Act (or whatever its replacement is called now) that I think contains definitions of what various periods of time mean, such as when they expire, although specific definitions in individual statutes will take precedence over these defaults.
Spontaneous gas leak.
in Boat Building & Maintenance
Posted · Edited by Ronaldo47
typos
I still have a jar of gas graphite grease of dad's ( he was a pipe fitter for the North Thames Gas). It still works, I used it a few years ago to re-grease a stiff tap on our gas cooker. In the 1970's, at my my previous house I found that the main stop cock had been leaking slightly when in the OFF position when I went to turn it on again after returning from holiday (at that time, insurance companies used to require you to turn off gas and electricity when houses were unoccupied) . Fun and games reporting it when I explained to the customer services person that, no, I didn't actually have a leak at present, I only had a leak when I turned it off, and it was definitely the stop cock that was leaking (checked with soapy water) , and that I was certainly not going to turn my stopcock to the OFF position as per her obvious gas leak script because that was what would cause a leak: I ended up talking to the supervisor, and when the gas man came, he simply tightened the stopcock plug nut with a large spanner as a temporary fix so you couldn't turn it off, and arranged for a crew to come and fit me a new one.
A couple of months later, a friend's newly-bought old house was found to have the same problem. I assured her that it was almost certainly not a case of the previous owner not hiding a problem, just a consequence of disturbing the stop cock that hadn't been turned for years.