Member postings for Paul Kemp

Just out of interest, what is the objection to a digital one? Best of both worlds?

Paul.

Agreed on both points. Mark is making a great job of it and shouldn't be concerned by the doubts that were expressed.

Paul.

Phil, Nick and Fizzy in terms of what was written are all correct. In the UK the model 'regulations' to get certification / approval all hinge on Nick's quoted para from the TEST code. We do not have a CONSTRUCTION code so any of the changes or approvals referred too depend on the individual tester's opinion and experience and if you disagree you then have some research into commercial standards to do support any negotiation with said tester.

Bob, maybe you can produce some calculations to convince us that the joint in question on the Minnie boiler is indeed substandard rather than form and then express an opinion based on observation and gut feeling? Maybe we should look at this from a different angle and consider how the boilers that have been previously built and certificated achieved that? Was it because it is a published design and therefore acceptable under the code and therefore no- one has previously questioned it?

I do not have any definitive information on the Minnie boiler like barrel diameter, number of tubes and size and the working pressure but making some very broad assumptions including a working pressure of 90psi and doing some very quick back of an envelope calculations I don't see much there that gives me any concern.

Paul.

Well I think it's scandalous it doesn't come with yellow Arctic cable.........

Michael,

It was less about "wot u rote" or the spirit in which it was 'rote' but more about what followed and general thread drift on this forum. Fellow just asked for info on his new machine not a critique of the electrical installation, if he wanted an opinion on that he would have asked the question differently?

Paul.

Good grief, only on this forum maybe? Fellow posts a picture of a lovely little mill with tons more versatility than an off the shelf modern option, horizontal spindle, vertical spindle, swivel table etc, asking for any info on what it may be and half the responses are focussed on the colour of the cable. He has only just got it, it's in his own private shed, it's not likely to be taken to a building site, is that really the most important thing? Does yellow Artic cable explode if it's used on 240v rather than 110? Has it got a far inferior insulation value or increased resistance? Come on for goodness sake look at the potential of the machine itself rather than dissing the cable! Who knows the fellow may be intending to scrap the motor, cable and switchgear.

Paul.

Yes, soft on completion (hence the advice when testing to increase pressure gradually)

Yes, it will harden in service, not strictly work harden as it won't be deformed beyond the yield (hopefully!) but it will harden due to stress / temperature cycles.

Paul.

If they did that they should be struck off! There is already an opportunity for that within the test code. There is also an opportunity within the test code where it requires supporting calculations to be presented for a non published or pre approved design for over zealous inspectors to make up their own requirements because there is not an accepted or referenced underpinning COP or standard!

Paul.

Acceptable TIG welds on copper for pressure vessels require low arsenic copper. Controlling the temperature of the 'job' is done by the settings on the machine and the wielding of the torch. As Jason said the TIG process per se has come a long way since a lot of the books were written, the most basic variants are AC and DC but getting more advanced you can adjust frequency and other parameters to suit the job in hand.

Paul.

True, there are a couple of other references as well but 'miniature' boilers especially in the road steam niche are increasing towards steel, the test code covers steel so to join everything up if we are to have a comstructional code it should also include steel.

Paul.

Duncan,

Thanks, I will send you a PM. I think I have a copy of the code somewhere although I may have given it away. More years ago than I can properly define through NAMES and I think it was Frank Cooper? A number of societies around the country were consulting with the Boiler Liason Group (I think that's what they called themselves anyway, been to sleep since then) on trying to thrash out a British code along the same lines as the Australian. If I remember correctly (and it's entirely possible I don't!) it gained some momentum initially and the 'rules' for copper boilers were pretty well there, it seemed to lose its way with steel boilers and I think because of the disagreements on standards it started to move towards producing a code for copper boilers only. I and quite a few others were not in support of this and because the differences couldn't be resolved maybe it just petered out. RSA were involved as were HSE (when they were still an executive and not a self supporting agency), 7 1/4" Society, SFED etc. I have a vague recollection this was around 1998 before CE and the PED were enacted but again that may be wrong!

Anyway I don't disagree with you and to get some real clarity in combination with the test code (which I think is fit for purpose with the exception of small boilers but not well audited) a code of practice would be a very useful way of doing it. That would allow departures from practice supported by appropriate evidence and a far more pragmatic way of dealing with it than a one size fits all set of hard and fast rules.

Paul.

Duncan,

Its a long time since I read it and in truth it has probably been updated since. Did you note anything re FOS and how they specify it is calculated? Nigel's comment re girder stays rang a bell, is it anything to do with the "girder" if permitted must be attached to the wrapper and the crown? I have heard several comments that the design is not accepted in Australia over the years but do not recollect a specific reason, hence my question!

Paul.

Nigel,

Thanks for that. As I said in my post I do think the Australian Code is a good document that gives some harmony to the nation's small boilers but I do think parts of it are well OTT. Like yourself it would seem, I don't see anything wrong with girder stays, anything but uncommon in full size. With a round top boiler the curved surface needs no additional support and the flat surface of the crown is ably supported by the girders. When you consider full sized unstayed crowns like the Marshall pressed Maltese cross and Fowlers "corregations" girders are eminently safe. Even rod stays will not prevent quilting of the crown but decent girders offer far more support.

Paul.

Bob,

I am not sure the size of your bank balance is of great interest to many and I am positive a large bank balance does not always equall sound reasoning or a sound appreciation of engineering principles. I suggest you spend some of it and add a copy of the Australian Boiler Construction Code to you library, it's not a document I fully agree with but it is well written and sets some common national standard. I was involved very much on the periphery when a British version was being considered but that seemed to quickly lose momentum, particularly with extending it to steel boilers.

The non issue with the Minnie boiler in another post I tried to reply to but due to the vagaries of this forum it logged me out instead of posting it and I can't be bothered to type it out again!

As an aside I have heard more than once the simplex boiler was not compliant with the Australian code but do not recollect a definitive reason why not. Does anyone have a definitive explanation as to why it does not comply? Too low FOS may be due to many reasons, plate thickness, joint design, stay size and spacing or type etc. Where exactly does it fall down?

Paul.

Strikes me that we are in a vey difficult position. I have no doubt SoD is correct with his figures but the underlying thought process as to which way GB should progress I think is flawed purely due to the amount of stuff we are reliant on foreign entities to sell us.

Take the current dispute with China over mainly Hong Kong and the recent decision to dump the Chinese kit. Granted that feeling was extant long before Hong Kong but it's now been brought to a head. So where will the new kit come from? I will bet a pound it is not designed and manufactured on this island! While we have been busy developing the service sector and reaping great rewards, mainly I would also bet from moving non existent money around we have steadfastly ignored being anywhere near self sufficient in terms of producing our own nasic and conditioned needs. Sure on a worldwide market we are un competitive on price for anything but high end and potentially military products.

The focus now is to deliver a product as cheaply as possible that has a design life of around five years or less and the customer is programmed to want the very latest model so nothing is designed to be repairable or long lasting - where exactly does that fit the green model or sustainability?

We have recently seen on this forum an effort to suppress the source of cheap foreign imports of dubious origin or legitimacy. That direction seemed to be supported by many of those that commented. However it is fine on a national basis to form our economy on cheap foreign imports and a focus on the service sector (where service for major products like telecoms is questionable). Why is that? I would submit it is because we have little choice and that is where we have positioned ourselves.

Paul.

Very good, I can think of a few variations too, for £2.50 and a few bits of scrap, oops sorry useful stuff you can't complain. I will keep an eye out at the usual bargain stores for similar. Thanks for the tip.

All we need now are the nay sayers to chip in and say how 'dangerous' this would be! I am sure some will be along soon!

Paul.

"Hence Mr Wheelers question if you saw it in time."

The mysterious disappearing post! I wondered about that as it vanished almost in front of my eyes, without trace!

Sense and sensibilities ensuring inclusivity and diversity I guess?

fpm is directly scalable from a Sherline to a Holbrook but that is where the similarity and theory end and why cutting speeds and feeds are recommended and not compulsory, dependant on tool material and geometry, machine rigidity, the way the work is held etc. The chances of getting a consensus on the OP question is about as likely on here as agreement on which lathe is best.

Paul.

Love it, very nice work.

Paul.

Amazing! Well done, fantastic results! Having had a small go at repairing clocks, then tried watches I definitely know my limitations and appreciate the dexterity (and eye sight!) required. Anything under 3/4" to the foot I keep well clear of these days but full of admiration for those that venture small and get results like that.

Paul.

I don't harden them, doesn't do your file any good if you run down on them! If you don't touch them it doesn't matter anyway. Easy enough to make so just make them as needed and if you wear en out either turn them to a smaller size or scrap em.

Paul.