Here is a list of all the postings Martin 100 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Safety of phone chargers|
Yes I agree as that is what I said, and you quoted
In a home consumer unit context rewireable fuses hung on for a long while. Rewireable fuses may at some time been the norm in an industrial engineering context but it must be a very long time ago, some of our systems replaced around a decade ago had elements of the original designs dating from the early 1950's and updated many times since. It was clear from the panels, the drawings and the documentation that cartridge fuses were always used, and in some parts of the modern implementations they still are alongside MCB's that can provide perfectly adequate means of protection.
Apologies for the long quote but the whole context needs quoting and preserving.
'electrical correctness' is not a word I would use to describe significant parts of what is said above.
Holding the view that rewireable fuses are 'safer' is staggering, they are by nature always slower in operation, they are prone to abuse, unreliability and early failure
The 3 to 5 times rated current for a type B MCB, and similarly for the other types is for a fault clearance time of 0.1 seconds. At around 2 x their rated current they will trip in around 2 minutes
A BS1362 plug top cartridge fuse rated at 13A requires around 150A to clear a fault in 0.1 seconds
Rewireable fuses are long since deprecated. Cartridge fuses or MCB's are the norm worldwide because they are good sound reliable and dependable engineering practice.
|Thread: Another workshop insulation question|
Ian, as mentioned above about third party certification, the electrical installation can be officially self certified by an electrician registered under any one of numerous official 'independent' bodies For instance NICEIC or NAPIT or Elecsa or Stroma (plus others too) The actual cost to the installer is so insignificant (about a fiver) it is totally lost in the labour and materials and rarely even becomes a chargeable item.
The conductor size proposed might appear 'over the top' but it might be proposed for extremely valid reasons. No one would deliberately use oversize cables as they are a pain to install.
One thing is clear, with a building where the construction of the structure is outside the remit of building control There is absolutely no need to pay ANYTHING to building control nor indeed for them to be involved at all. Plus I doubt there is now a building control department anywhere in the UK with any valid expertise on electrical installations.
You appear to prefer to circumvent the requirements for a fixed installation by using an extension cord. A 'new ' installation must legally meet the basic safety requirements, they are a couple of paragraphs specified in part P and are met by complying with BS7671 or by an equivalent IEC standard. That requirement is usually ensured (in the case of those not appropriately skilled) by employing someone competent and who can self certify, not by employing someone to install and then paying hundreds of pounds to building control (only for them to employ a subcontractor)
For those appropriately skilled and qualified that deem part P certification an insult we, as ever design, install and test our own installation to fully meet the requirements (and some of us would if necessary be prepared to argue our case in court)
Your extension cable is not and never will be a safe substitute for a properly designed and earthed outbuilding installation. It could, regardless of your specially installed outdoor sockets, kill you or someone else. That situation may arise as a result of issues occurring outside the boundaries of your property and totally within the remit of your distribution network operator, and while your installation within the house will, if properly installed remain safe at all times, your extension to the outbuilding and particularly exposed metalwork on any machinery will not.
As dirty harry, the well known electrician allegedly once said, do you feel lucky?
Except anyone with any sense would plan their workshop size, location with respect to boundaries, location to the main property and the method of construction to ensure 'planning' and 'building regulations' did not apply. Then there would be absolutely no fee to pay for anything.
The an earth has to be exported along the SWA cable from the head end, it will almost always be the PME earth connected to the armouring to ensure suitable fault protection and fault clearance times for the cable. The cable merely has to be installed to prevent any damage. Burying is not always required, but if it is then burying has to provide some warning to anyone coming along, commencing a dig and encountering the conductor 'hidden' just below the surface. The cable depth of burying is only specified for the main incoming feed into a property and network operator feeds in the carriageway and pavement. Anything on your own property with a sub main or individual circuit is not prescriptive as to cable depth. There are recommendations but that is all they are.
In addition this 'exported' earth then has to be totally isolated at the outbuilding and a local earth provided unless you have means of adequately ensuring against rise of earth potential from a fault or lost neutral which is what the equipotential bonding is there for in the main property.
Cabling with a flexible extension cable can easily lead to a situation where a fault occurs and is not cleared in time, leading to a fire hazard and a shock hazard when metalwork within the outbuilding installation rises above the potential of the local earth. Just plonking an RCD in the installation at random locations may not be enough.
It might all be viewed as just 'part p' and denigrated in some / many eyes but in reality an outbuilding electrical installation requires a common sense properly engineered electrical installation that in the case of a new installation meets the requirements of BS7671 or if you want to be pedantic the equivalent IEC requirements.
Fail to comply either as a 'pro' or an amateur and it results in injury and you will almost certainly be prosecuted even if you have subsequently moved house.
But your biggest problem was wanting to build something that requires Planning and Building Regs. 15m^2 timber or or 30m^2 brick / block / stone should be enough for most 'home' workshops. If you live in a national park or other location protected from development then you have some sympathy.
Forgot to add you can get an electrical installation in a structure outside the remit of building regulations (separation / use etc) 'certified' by an appropriate person / organisation without any building regulations application being made.
Edited By Martin 100 on 08/10/2018 14:10:00
|Thread: Aldi Charger - Confidence Dented|
+1 on the wonders of lead free solder. Give me lead and tin with a tiny sprinkling of silver and a non corrosive flux core any day. Almost 100% reliable joints almost 100% of the time.
The Restriction of Hazardous Substances directive has probably produced more landfill than any single act in recorded history. Thank goodness exemptions were made for medical and defence products (plus some others) otherwise we'd all be living in caves using leeches and making stone axes, all we have to account for is the telly and all other electronic items only lasting the guarantee period plus 'a bit'
There is an entire industry that takes brand new traceable lead free electronic components, strips off all the lead free solder, tins them with leaded solder and then repackages them on reels for series production of reliable kit. Can't sell any of it to Joe Public though, it's far too 'dangerous' the lead could kill and 'cause birth defects in the state of california'
I've heard a common failure mode with the c-tek intelligent charger clones sold by Lidl & Aldi is the one moving part, the push button switch, which could be down to moisture or flux ingress. Touch wood not had an issue with that here.
|Thread: A Big Treat coming for Readers of MEW|
Really the cloud should be nothing more than storage, but we all know it isn't. Somewhere, somehow we sign away rights so someone, usually the likes of Google can pillage our emails and search history and everything else we do online to force 'targetted' adverts upon us. Once upon a time google's doctrine was 'do no evil' they somehow forgot that a long time ago. Adblockers and no-scripting and even things like the TOR browser help somewhat.
With CAD & CAM they give us lots of 'cool' functionality sometimes 'for free' but that comes with a creeping intrusion into the very soul of a company or inventor. Even though I use F360 I really do not want Autodesk to know at all that I'm thinking of making product x with machine Y and months or years before product x is manufactured they know so much about product X they can cross reference me to public records or browsing history or whatever.
You'd hope with GDPR and the severe penalties it brings then things would be secure and free from prying eyes but I doubt it really is. Yet with ideas and designs in the cloud you should be secure from that sudden, sunday afternoon on the sofa laptop hard disk crash that wipes out months or years worth of work and takes down a fledgling company (or even a mature one with flaky IT infrastructure)
I've had Alibre trials in the past, never stuck with it because of the learning curve and lots of other things that need more of my attention that by the time it might have been useful the low cost of entry had simply evaporated and slinging 400 quid as opposed to the 99 quid it was a few months earlier was way beyond justifiable.
This extended trial might even persuade me to get a subscription to MEW
I downloaded the 2018 version of the 'free' Solidworks eDrawings Viewer a while ago as the previous version became incapable of handling newer file versions. To enable the download they require all your contact details regardless of if you are using the viewer commercially or at home (in hindsight 'fake' details with a disposable email address might have worked) . Since then the sales rep has contacted me several times by email wanting to run a demo 'at my premises' and now they are in contact yet again offering three years interest free credit on a Solidworks licence.
In contrast despite 'using' Fusion 360 for a long time there have so far been no attempts to get me to pay to upgrade.
But ultimately I wouldn't trust any software that relies on 'the cloud' nor indeed any software that requires an activation process or a dongle and I'm not sure the 'free' use model for F360 will remain forever. While cloud storage may be useful in backup capability and flexibility in location of use it can also go very wrong with designs lost or leaked.
For most use cases just sell high quality properly debugged software to me on durable media, that I can copy myself, at a reasonable price, if necessary give me a key that will never ever expire regardless of any hardware upgrades I make, giving me software on a platform that will be around as long as I decide. If it's complicated enough to use then provide a support forum that is free to use and above all make your sales people simply go away until I decide I want to 'upgrade'.
|Thread: How much do Colchester spares cost ?|
One thing I heard about car spares (at least those made by Ford) was the price was set, a batch was produced and as long as that stock lasted at the central warehouse the price stayed essentially the same, without an annual escalator. Once the part required manufacturing again, even on the self same tooling, a whole new price was established. Something, I can't recall exactly what, it may have been a gearbox synchro ring used on a Ford box fitted to a Caterham 7 went from about 3 quid to about 40 quid 'overnight' about 20 years ago. The original parts had been around in their hundreds if not thousands since the 1970's
Some low volume car manufacturers liquidate their excess spares stock 'at or around cost' or even a few percentage points above scrap value a few years down the line. But you can guarantee it's never all the bits you really need
Edited By Martin 100 on 02/10/2018 10:30:26
Funny you mention silver plated nuts and quote that price. Bought some silver plated nuts just the other day. M10 x 1.25 stainless K nut silver plated, essential for mounting a turbocharger to exhaust manifold and then actually being able to remove it years later without trashing the exhaust manifold or the turbo (access even on the bench is VERY tight) - 100 off price £900+, rising to nearly £13 for low quantities.
I remember doing a 'refresh' on my early 60's Boxford possibly in the early 90's The prices were eye watering then but at least they were still available new off the shelf which isn't the case for a lot of things now.
Just how much did the various lathes mentioned above (and others) cost when new?
When anyone complains about the price of something today then this can be useful
|Thread: Hut Consumer Unit & MCB Question|
Legally it's 13A total regardless of whether the socket is one way or two way. Three way sockets are also available but are sub fused at 13A in the faceplate.
The BS approval test on a double is 20A (with a 70/30 split) with a limit of 1 deg C rise
BS1363 sockets from reputable manufacturers will actually accommodate 3 x 2.5mm^2 or 3 x 4mm^2 or 2 x 6mm^2 conductors.
Petrolhead that cable isn't Steel Wire Armoured, this is SWA
We might possibly be into can of worms territory here...
For anyone seeking guidance here is a good place to start (although getting a bit dated now)
The MCB's , like fuses should always be rated to protect the cable. An appliance you plug into a '13A" socket will often as not have a flexible cable rated at lower than that, hence lower fusing in plugs such as 3A. Meanwhile in the rest of the world, with unfused plugs and radial circuits such devices are protected only by a 16A MCB and an RCD.
If you have a ring main run in 2.5mm^2 Twin and earth or singles in conduit then 32A might be appropriate. For a radial circuit (i.e. one cable from the consumer unit to each socket in turn without another cable returning to the consumer unit) again using '13A' sockets or BS4343 'industrial' sockets 16A would often be more appropriate. A 16A MCB might indeed operate before a 32A MCB and a B rated breaker before a C rated breaker before a D rated breaker, but they are not strictly interchangeable and the type and level of fault could mean they all operate together, regardless of rating and trip curve within a few hundred milliseconds and thus provide no effective discrimination
Downrating an MCB from 32A to 16A does not enhance 'personal' protection, the Residual Current Device and the earthing does that. Segregating the lighting and power to equipment is a good thing but a fault on the equipment could still plunge you into darkness, with resultant injury from trip hazards. Hence why RCBO's (a combined MCB and RCD) on each circuit are preferable, further enhanced with the lighting split across two circuits. Of course if you have windows on your workshop and only work in daylight this is not really an issue
Yes you could let the feed stop before reversal but equipment shouldn't routinely trip protective devices regardless of what the user does so this discussion is IMHO far from being 'pointless' and a wrongly sized breaker can be a fire hazard, an incorrectly earthed installation in an outbuilding can be a shock hazard. Because it hasn't killed you in 30 years does not mean it won't kill you tomorrow
The rating and type of the MCB's will, if the system has been properly designed , be correct to protect the cable (at the head end) and separately the installation at the hut end, with discrimination such that a 'local' fault stays just that.. To have MCB's identically sized is not ideal and may be totally incorrect, indicating that the installation was possibly just guesswork.
If you are only using one bit of machinery at a time the 32A MCB in the hut could be sensibly replaced by one rated at 16A but that won't necessarily stop the tripping problem.
A physical check of all connections (phase neutral and earth) from end to end plus checking earth integrity on the equipment is a good idea.
MCB's can be supplied or even go trip happy so a direct 1:1 replacement of all the existing protective devices might possibly 'fix' the problem.
Simply swapping the an MCB from a type B to a type C or even a type D without being fully aware of the implications of such a change is not a sensible idea. It might not provide enough discrimination which is what you are after and it could degrade the effective level of protection on the cable from the head end to the hut end.
But as ever, without having sight of the installation, the earthing arrangements and measurements of the fault level most of this advice is just 'guessing'
|Thread: Boxford Model A backlash|
You are not looking in the right area. Look instead at the handwheel end of the cross slide screw. Unscrew the chromed slotted 'nut' (anticlockwise with something that doesn't damage the slot) Now undo the hex socket grubscrew that holds the handwheel to the cross slide screw. Now fit the handwheel to remove all slack, tighten the grub screw Refit the slotted nut.
As for spares, you are out of luck for that area of the lathe because that type of cross slide / dial was discontinued in the early 1960's
|Thread: Another workshop insulation question|
No, the exact opposite
Lower is better
Decide if you want to be able nip out for an hour or two 'whenever' and at any time of year, do some work in normal clothes rather than multiple layers of thermals and then come back inside when you choose, not when you freeze / melt.
Decide how much time/money/effort you want to spend on 'heating' No time/money/effort is often the best.
Do you prefer to be sweating all through a hot summer with a fan trying to cool the place down?
Do you prefer to be a gross polluter for the rest of the year with a woodburner affecting the health of everyone in the vicinity?
Some fit resistive heaters or incandescent lamps to every bit of machinery to stop them rusting when getting the insulation and ventilation right fixes the problem 'forever' with no ongoing energy usage. But some people always go for really cheap nasty 'fixes' rather than properly addressing the fundamental issues.
Proper insulation is expensive but needs buying and fitting just once. Do it right and occupancy heat, maybe topped up with that from a freezer can easily be enough to keep the place comfortable all year round.
If you can only afford 25mm of polystyrene on the walls then don't bother, wait until you can afford at least 75mm and preferably 100mm or more of PIR
While PIR is supposed to be 'safe' and class O, bare PIR on the roof is not a good idea if you have any intention of having a naked flame in the workshop. Trying to justify leaving it bare to enhance lighting is daft. Put some more lights in instead, preferably ones that direct the light downwards, they are really cheap.
The floor will also loose lots of heat, cold feet can be fixed with insulation in the structure too
|Thread: Record No 1 vice pin sizes|
Size of the pin punch? a bit smaller than the small side of the taper pin, it also means you have something around the size of the pin to compare with so you don't accidentally hit the wrong end of the pin and possibly make an easy job something else.
Hitting something hard like a pin punch with something hard like a hammer will indeed work, but copper dulls the shock back up your arm, doesn't damage the striking end of the pin punch, means you don't really need eye protection and leaves the hammers with nice clean shiny faces for hitting nails accurately.
It's around 10 quid for a Thor copper & hide mallet, it gets used for tapping down work in the machine vice on the mill and tightening the vice handle, the latter always with the copper face The current one has had maybe a decade of use so that's something around 1/4 of a pence per day.
The size of the pins? Measure the holes afterwards. Having dismantled one of mine recently to fit copper jaws (the screws, 1/4 BSW around 3/4 inch long were very stuck and needed spotting with an end mill, then left hand drilling on the mill with one requiring heat to remove)
The pin holding the nut into the main body at the rear of the vice is somewhere around 3/16", the one on the screw a bit smaller, possibly 5/32", but they could be metric, I never measured and simply refitted the ones I removed.
Besides the slight variation in taper (1:48 &1:50) metric pins are measured at one end, imperial ones at the other and at the moment I can't recall which is which.
Removal? parallel pin punch, hit with a copper & hide mallet, not much force needed at all,
The one on the screw will catch you out if you drive it through too much and jam up the screw and prevent if being turned, so partial drive through, rotate the screw 180 degrees and pull out the pin with a pair of pliers / mole grips etc is the better option.
|Thread: Illegal CD copy|
It's not very complete either as the last issue was number 4593 and this collection apparently only has somewhere around 1600 mags.
There was, many, many years ago, long before this forum ever existed a collection of ME's from a public library in the US that were scanned and OCR'd. That collection was distributed person to person, for free or just the cost of the media if I recall correctly, on something like 20 CD's, so at 650MB it totalled around 13GB or around 3 DVD' s. It covered up to the 1980's with lots missing, no idea how many magazines were scanned.
The UK situation might be different but pre-1923 issues would be out of copyright in the US, with multiple authors per issue it's not 100% clear what is the status of the rest of it.
The legalities are indeed questionable, but the usefulness of having something essentially archived forever and readable without repeatedly thumbing through increasingly fragile bits of paper taking up lots of shelf space and with rusty staples are IMHO immense.
|Thread: Dangerous Ultrasonic Cleaner Electrical Failure|
Yes something quite visible that could indeed prove fatal. One would that with the 3 pin inlet and the metal case it is properly earthed.
I've seen quite a few glass fuses vaporised, the tails and end caps of the solder in type often being the only evidence left.
I would hope most if not all would recognise that method of construction as a major issue but as shown many moons ago on here a simple mains USB power supply feeding a seemingly 'harmless' LED lamp 'at 5v' has the inherent potential to kill because some USB power supplies, usually offered into the market by backdoor suppliers are, by design, built with near zero separation and are thus totally incapable of meeting any safety standard recognised in the UK/ Europe/Australia/USA.
|Thread: Increasing cost of entry into model engineering|
Without the likes of ARC or Axminster etc I would suspect few here would ever have a 'new' mill or lathe. Same with machine vices, rotary tables, dividing heads, tool grinders, quick change toolposts, angle plates or a myriad of other things. In the past they'd spend years (or even decades) machining a set of raw castings often following a series lasting dozens of issues in the magazines and then at the end maybe forget why they made them in the first place. Old machinery is also quite simply way too big for many home workshops, something compact is usually all many actually need. Something heavier and bigger with significantly more stiffness would always be better though.
Despite the immediate additional cost I'd sooner buy much (but not all) of what I need locally than trust a supplier thousands of miles away with a dubious or non existent return policy. But when you can buy the identical item to that sold by a UK supplier for 60% of the price, delivered within two or three weeks you wonder how sustainable in the long term the UK pricing model is.
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