Not fit for purpose

[Nathan SharpeParticipant @nathansharpe19746]

One of the very basic skills of engineering is the ability to read and interpret a drawing. This means using eyes and brain to pick out problems before you hit them. Yes we are generally amateurs and work to drawings done by other amateurs but we took up the hobby to produce something we could be at least happy with and learn something as we did it.

Given that most problems with the drawings have been encountered by other amateurs the best advice is the oldest advice" join a local club/group" and use their accumulated expertise.

As already posted even the most up to date industrial/commercial drawings WILL contain errors/omissions and mistakes.Try reading the drawings for a hospital's M+E and you would need six months to find the potential problems, do you complain about OS Mapping/Road Atlases/Satnav Mapping because they are not accurate (even the day after survey)? No, you do not, because these are things that you accept are only going to to be upgraded and amended from time to time. The same applies to Model Engineering drawings, but the CAREFUL and SKILLFUL engineer will do their research before buying drawings. They will have joined the club/usenet group/looked at other Mod Eng sites before spending money??

Model Engineering is for expanding your skill and enjoyment not to guarantee a 100% build without any problems. If you want a 100% guarantee of build first time either stick to Airfix or do nothing would be my advise.

Drawings are and always have been a guide only, they are fit for that purpose, YOU have to provide the skill. If you can't is it you who's not "fit for purpose"?.

[David Paterson 4Participant @davidpaterson4]

Some of this is silly.

Now that's off the chest, the one specific issue that I would have with drawing errors and 'fit for purpose' is with safety. Many of the complex plans contained in ME include boilers. There are two issues with this. Firstly, plans may not comply with safety regulations or standards in different countries, and secondly, they reallly should be checked thoroughly against relevant standards in the UK before republishing – the standards may have changed.

I do recognise that almost all of the discussion in forums like this around boilers highlights the issue and recommends an appropriate procedure – join an club and do the build under supervision of the boiler inspector.

When I built mine, I had the original Harris book and the AMSBC code next to each other when I drew my plans, but its not certified.

Over all, the plans are a great resource to understand how things work that are at an affordable price – I have one on the wall – a wooden toolchest that is an American classic. But then, I also have framed the tech school poster for the Hercus lathe in the shed.

cheers

[JasonBModerator @jasonb]

Posted by Nathan Sharpe on 10/05/2012 22:42:22:

Drawings are and always have been a guide only, they are fit for that purpose, YOU have to provide the skill. If you can't is it you who's not "fit for purpose"?.

So where does this leave the beginner? Nathan you are new here and may not have followed the portable engine threads for example, this is a model aimed specifically at the beginner and at times even I have found it hard to follow but have found many errors.

These problems are what will drive beginners away as they will become despondant when things need remaking, don't fit and run poorly. There are many who don't want to be in a club so they will be left thinking its them who are "not fit" for model engineering and give up before they start.

I agree we will never get rid of errors but now with teh net at least if problems are raised a bit of googling should find these problems before metal is cut and help others into the hobby.

J

[Ady1Participant @ady1]

I think you're over-analysing the situation

Anyone taking up the hobby has to jump over a whole bunch of hurdles and acquire experience in various disciplines before deciding on taking a specific project and is well aware that there will be more unexpected hurdles to overcome before success is achieved

 

Model engineering is a hobby which is a challenge from day one

If you don't thrive on solving real world problems and challenges you definitely won't make it in the hobby anyway

 

The biggest problem for the hobby now is government muppets:

Diesel fuel restrictions for model engines

Not allowed into scrapyards for access to cheap materials

Boiler regulation issues

 

These problems are almost impossible to overcome because they are laws

A few errors on a plan are the least of the hobbys problems

 

The first thing you have to consider is:

Am I allowed to do that and how do I get around the legal barriers

 

I got a whole bunch of gear and plans together before discovering that model engine diesel fuel is virtually impossible to acquire because of government morons

Project now abandoned

Will revisit if I can acquire any fuel.

 

Other projects have been abandoned because of the recent Scrapyard laws.

Big chunks of steel from a dealer aren't cheap, scrapyards were great for acquiring cheap metal, chopping it up…making a hash of it and getting more materials cheap for having another go

 

…problems with plans never came into it… problems with plans were the least of my problems

Edited By Ady1 on 11/05/2012 08:09:36

[David HanlonParticipant @davidhanlon38496]

So the discussion rumbles on, but with a twist regarding beginners and the Portable Engine. As a complete beginner myself (just completed a wobbler and working on trying to get parting off to work …) Here is my opinion on this for what it is worth.

1. Thanks to the Author for spending the time and effort to write the thing in the first place, as a professional (not mechanical!) engineer I know the financial rewards for an article published in ME/MEW are no where near matching the time and effort required for this.

2. Thanks to David for starting the Portable Engine Thread which I have followed with interest.

3. Thanks to JasonB for his many inputs to that thread.

and now we come to my contribution …

Combining all the above – my assessment was to leave this project well alone until

a. The design settles down (you know – never buy version 1.0 of anything!)

b. I have completed a few simpler projects ( A wobbler and a Stuart V10 (Thanks Cath!)) that are on the bench,

What I would REALLY like to see would be for JasonB or some other experienced ME to get together with the original Author and with David, Build one of these and then write up his experiences so that us beginners can see how you transform published plans (warts and all) into a working model. Integrate that with the beginners series running in MEW at the moment and you have the start of a really good MODERN resource/training program/co-authored book aimed straight at beginners (well me at least)!

Best Regards

Dave

[Ian S CParticipant @iansc]

Nathan, you can't even rely on Airfix (etc), in my younger days I used to build Airfix models, I also used to get the RAF Flying Revue, it had a section on how to correct the mistakes in the models, as well as how to modifie a kit to produce a different version of the aircraft type. Mind you some Dinky Toys were wrong, and now are valuable collectors pieces. Ian S C

[Mark P.Participant @markp]

You should have seen some of the drawings we got from Boeing and Airbus they were full of mistakes!

Pailo.

[SteveWParticipant @stevew54046]

How about a plan rating so that a beginners plan would be VERY WELL checked and as near to 100% as possible but some plans could be rated for the 'advanced modeller' and subject to a higher risk of error.

Putting intp print a beginner's plan that has obvious errors was just not fair. And of course there will not (unlike drawings with issue and correction notices) be any real way for the beginner to get the PLAN corrected. He/she will be left to trawl through this forum or ensure he/she purchases future copies of the magasine in the hope that they will spot some notes at some time in the future.

SteveW

[Steve GarnettParticipant @stevegarnett62550]

Posted by David Hanlon on 11/05/2012 08:05:49:

What I would REALLY like to see would be for JasonB or some other experienced ME to get together with the original Author and with David, Build one of these and then write up his experiences so that us beginners can see how you transform published plans (warts and all) into a working model. Integrate that with the beginners series running in MEW at the moment and you have the start of a really good MODERN resource/training program/co-authored book aimed straight at beginners (well me at least)!

On the face of it, this seems like a good idea, although it's not snag-free. The issue here comes down to in the end to the question 'what do I do, because x doesn't appear to make sense in the drawing?' – and the answer to that question is always going to be different. And, because everybody has different facilities available to them, some of the prescribed answers simply wouldn't fit; you'd clearly need to go further than that. And peoples' expectations vary (like the responses to this thread…); some people just want the answer spoon-fed to them, but others relish the prospect of solving problems for themselves. It's quite hard to say what I really want to here, because it almost sounds rude – but I believe that some people appear to have conceptual problems with problem-solving, and unless an article deals straight up with their particular problems, they're still stuffed – they can't universalise the advice given. So the whole thing's a bit of a Lion's den.

But do we really need the article(s), or is there something available now? I'd suggest that we might already have a large chunk of it currently appearing in installments of MEW in the form of the Stepperhead series. Okay, I suspect that some have ignored it because they think it's CNC-based, and others think that it's seriously advanced, and are wondering why they'd ever want to build one. But for a beginner there's some seriously useful information there, because it describes, with drawings, the way it was actually made, and with useful machining tips, etc. So for anybody in the ab initio stage, very well worth reading, I'd say.

As for the drawing errors thing in general, I'd say that the best thing you can do is teach yourself to draw, and then make the things you draw, preferrably six months after you've drawn them – that will teach you more about interpreting drawings than any article will!

[Martin CottrellParticipant @martincottrell21329]

Posted by Steve Garnett on 11/05/2012 2012

…… some people just want the answer spoon-fed to them, but others relish the prospect of solving problems for themselves. It's quite hard to say what I really want to here, because it almost sounds rude – but I believe that some people appear to have conceptual problems with problem-solving, and unless an article deals straight up with their particular problems, they're still stuffed – they can't universalise the advice given. So the whole thing's a bit of a Lion's den.

Steve,

I don't think this is about the level of help (spoon-feeding) that beginners are expecting. If someone, beginner or experienced engineer alike, wishes to build an exact replica of something someone else has made he has two choices. He can either access the original model and dismantle it to take measurements and reproduce the parts or he can follow a set of plans which also provide him with those measurements. I don't think it is unreasonable to expect that drawings will generally have been checked for accuracy and completness especially if the builder is paying for them either having bought the magazine or a set of plans from a third party.

I understand that errors can sometimes creep in but I don't think that fact is necessarily pointed out to beginners. David Hanlon made the very good point that maybe articles intended for beginners should be scrutinised a lot more carefully prior to publication coupled with a beginners series that encourages the beginner to study the drawings as a collection of interlocking, interacting components rather than just a pictorial list of individual parts.

I think beginners are looked down upon from some quarters in this hobby. It is just a hobby for many of us, we're not engineers by trade. We're not here to re-invent the wheel or jump through hoops solving riddles to achieve an end product we just want the satisfaction of having made something with our own hands. Ease us in gently and we'll more than likely come back for something more challenging, make it unnecessarily difficult and there are plenty of other pastimes waiting to take our hard earned cash!

Regards, Martin

[John HaineParticipant @johnhaine32865]

Here is an idea – Open Source Drawings. Some of the best software around now is Open Source which anyone can download, use, modify, and (subject sometimes to conditions) re-distribute.

There are some very good freedrawing packages around – e.g. SolidEdge. Anyone can download these and use them for non-commercial purposes, and anyway quite a few MEs now have CAD.

So, if drawings were made available on-line in suitable format, then people finding errors could modify the drawings, improve them in other ways, submit them back with the changes to be incorporated in the orginal, and/or re-distribute them. There could be micro-businesses for those with CNC machines to make tricky or tedious components to order using CAM to generate Gcode from the drawing files (think, castings).

All this is possible now, ME/MEW could facilitate this. Of course it might threaten part of their business, but as the saying goes, if you don't come to the banquet as a guest you are likely to be there as the meat. How about it, Dave?

[Nicholas FarrParticipant @nicholasfarr14254]

Posted by John Haine on 12/05/2012 07:34:03:

So, if drawings were made available on-line in suitable format, then people finding errors could modify the drawings, improve them in other ways, submit them back with the changes to be incorporated in the orginal, and/or re-distribute them. There could be micro-businesses for those with CNC machines to make tricky or tedious components to order using CAM to generate Gcode from the drawing files (think, castings).

Hi John, all very well, but the proverb; "Too many cooks…………" springs to mind not to mention potentially many more mistakes and interpretations distributed.

Regards Nick.

[Eric CoxParticipant @ericcox50497]

As with most forum posting the comments evolve and deviate from the original concept.

In this case I wanted to highlight the fact that drawings were sold/published with obvious errors that could be recognised by simply looking at the drawing without the need of building the model or having a degree in drawing office practice, in other words, "proof reading".

I don't expect to be "spoon fed" but do expect the drawings to be to a minimum standard or quality and free of "obvious" errors.

[Steve GarnettParticipant @stevegarnett62550]

Posted by Martin Cottrell on 12/05/2012 00:30:12:

Steve,

I don't think this is about the level of help (spoon-feeding) that beginners are expecting. If someone, beginner or experienced engineer alike, wishes to build an exact replica of something someone else has made he has two choices. He can either access the original model and dismantle it to take measurements and reproduce the parts or he can follow a set of plans which also provide him with those measurements.

Hmm… so if people have a choice, and some are happy to resolve issues themselves and others aren't, it isn't about the level of help? Think you'll find it is…

I don't disagree about drawings though – well, in principle, anyway. I'm not sure that I entirely agree about which drawings ought to be scrutinised more – I think that in an ideal world, they should all receive the same degree of scrutiny! The point about beginners being made more aware of the potential issues with drawings is well-made though; it takes a while to get into the swing of interpreting drawings, and even when you are used to this, you can still make mistakes with things like machining order, etc.

And that's the point really – it's about levels of interpretation, and this will vary between individuals. There's a lot to be said, when supplying just a set of drawings, for supplying varying degrees of additional information – experienced builders won't necessarily need much, whilst beginners might need it almost step by step. And it may well be that the person who goes though a drawing preparing the step-by-step instructions is the one that discovers the mistakes…

I'm not for one moment suggesting that what David Hanlon wants is wrong, per se – just that it's not quite straightforward, and also that it's going to increase the cost of a set of drawings somewhat to include all this additional information. But that might be a good thing, because it would encourage people to discover and learn enough to be able to make models from a simpler, cheaper set, wouldn't it?

I think that the whole issue has to be considered carefully, from more than one point of view, if it isn't going to create more heat than light, that's all.

Regds, Steve

[Alan JacksonParticipant @alanjackson47790]

I worked in various drawing offices for many years and checking drawings often took more time than drawing them and mistakes still got through the system. To sign off a drawing as checked meant that you were responsible for the design even though you were checking something that you thought was a bad design or idea it became your responsibility. There is always opinion in checking due to not liking the particular way it is designed (I would not have done it that way) and personal preference so it is a minefield for politics and dissent. Because the checking process was so time consuming and always at a time when everybody required the drawings yesterday the checking process was subject to, shall we say shortcuts. I was once asked to do an 80% check to save time. You know just check the bits that are wrong not all of it. The only way to find the bits that are wrong is to do a 100% check. I also do not think the process improved when computers replaced drawing boards. You could see at a glance on a drawing board if the draughtsman was up to scratch and this is completely masked in the uniformity of computer drawings they all look good.

Regards

Alan

Edited By Alan Jackson on 12/05/2012 11:22:43

[David Clark 13Participant @davidclark13]

Open Source modelling

I have started a new thread on this topic

New thread

First we need to decide on a model.

Please use the new thread to discuss this. Put your reasons for and against suggested projects.

I think the first few projects should be beginner related.

Drawings should be in DXF format but can be posted here as jpeg.

I can probably host DXF drawings at http://www.ml7.co.uk

regards David

Edited By David Clark 1 on 12/05/2012 11:54:25

[David Clark 13Participant @davidclark13]

Hi There

Looks like the long links have been disabled.

I posted a link and it came up as **link** and it did not appear to work.

So, please use the link function to insert link.

I assume this is a designer change.

regards David

[John Stevenson 1Participant @johnstevenson1]

Who would even dream of asking if a set of drawings were fit for purpose ?

Is it the guy in front of me who goes into Sainsburys and pokes every apples so they are bruised ?

Is it the guy who squeezes every loaf of bread so the one I pick up is work hardened to 65 Rockwell ?

Come on guys the mantle of the anorack wearer is fast becoming transfrered from the train spotter to the Model Engineer.

[merlinParticipant @merlin98989]

I think that anyone buying drawings or plans could reasonably expect at least an additional slip of paper listing any available corrections.

A few years ago I bought a quite expensive book on the construction of a clock, which contained many unclear statements, some printing mistakes and much out-of-date information. I wrote a letter of complaint but received no reply from the author.

I expected the challenge to be in the making of the clock, but it is in understanding the book.

[Richard ParsonsParticipant @richardparsons61721]

Ah new software! These days software is not 'released it just 'escapes'!

Rdgs

Dick

[HowiParticipant @howi]

Unfortunately ME plans are no different to anything else, whether it be electronic circuits (and/or PCB's) computer software or what have you.

I have been into electronics for many years, you would be surprised at the number of 'Published projects' that may be complete with circuit diagram and PCb layout, that have never actually been built to prove they work. The ones that have actually been built will usually suffer from wrong part numbering, wrong part value, PCB that needs correcting etc etc.

This can be very frustrating, especially for a begginer, as you might imagine.

One's first approach to a plan or circuit will usually assume that everything will be correct, only experience will make you wary about taking that assumption for granted.

I understand the writers frustration, but at what point does a plan become 'not fit for purpose'? how many mistakes are allowed? What about minor mistakes to major mistakes?

Over a period of time one would expect corrections to be published as the number of people build to the plan, but these people have managed to suss out the errors so why not you/us?

As with anything you buy 'caveat emptor'' applies.

I have tended to look on plans etc as design ideas rather than completely accurate projects, for the above reasons, the more complex the plan/design the more likely I would be to do a lot of cross checking before taking a single cut.

Always assuning the worst, will lead to less frustration in the end, (the proverbial 'pinch of salt'…..)

[RickParticipant @rick]

What a lot whingers. I've purchased drawings from Myhobby Store and found them to be OK. Surely you examine the drawings before you build. That's a normal standard. Any mistakes can be then sorted out and marked on the drawing. It's not very hard. I worked on laser, radar, and infra red absorption analyis and circuit diagrams from the manufacturer had mistakes, but it was up to you sort them out.

For the price of the plans I think they are of good value. As others have stated, use your brain. You will soon learn how to interpret the drawings and this I feel is a great benefit. By doing so, you will soon be able to sketch up your own.

Don't blame David. He does a damn good job!

Regards

Richard from South Australia

[PeteParticipant @pete41194]

Normaly I wouldn't go against Davids opinions since I've found him to be very fair. His first comment was to me rather humerous also.

I can see and understand a new design having mistakes within it. That's understandable. While I don't know the exact process used to print the drawings today that My Hobby Store sells, and I'll refrain from getting into the fit for purpose issue. I do have a issue with the old drawings that contain well documented mistakes.

The George Gentry designed Model Engineer Beam Engine for example contains at least 11 mistakes that I know of. These drawings have remained unchanged for at least 30-40 years and possibly much longer than that. AFAIK Revees and My Hobby Store still sell these drawings without including a single additional sheet with those corrections listed that would be most welcome by any builder, and in todays world it would be almost impossible to add more than 10 cents in cost. I'm certainly not faulting David for this since it's not part of his job and the needed corrections should have been done decades before he became editor. So to be a bit logical about this? My Hobby Store, Revees, and any other supplier of drawings we use do have an obligation to at least correct the drawing mistakes as there found. Instead those mistakes are generaly ignored, and year after year different builders get the joy of rediscovering those same mistakes again and again. That is and would be a comman and important item for any company that cared about their customers perceptions in my humble opinion. That's not too much to ask from any company no matter what they sell. Or at least it shouldn't be if they want to remain in business today. As the end users and the people who keep Model Engineer and Model Engineers Workshop magazines going. I think we well deserve that minimal amount of attention to what My Hobby Store is selling to us. Any older drawing should by now be 100% correct. To say otherwise is illogical.

 

Pete

 

Edited By Pete on 30/06/2012 09:26:56

[Michael GilliganParticipant @michaelgilligan61133]

Pete,

Excellent comments !

However, in the absence of Errata from the Publisher … perhaps this forum is the place to log all of those errors & omissions that builders find; together with their proposed fix.

MichaelG.

 

 

[David Clark 1]

Would you be prepared to create one thread for each of the available drawings?

… kept specifically for this purpose, and using the Drawing Number as its title.

 

 

Edited By Michael Gilligan on 30/06/2012 10:18:29

[David Clark 13Participant @davidclark13]

Hi Michael.

We can do that.

Not a problem.

Pete, there is a problem.

We cannot change drawings because people point out errors. Repeated errors have been checked in the past and not all of them were actually errors, just builders misunderstanding the drawings.

If we did change the drawings, we would have to build the entire model from scratch to ensure it was an error and also that we had not introduced further errors. Clearly this is not possible.

regards David

Edited By David Clark 1 on 30/06/2012 10:44:15

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