Technical and engineering drawing.

[TerrydParticipant @terryd72465]

Hi Guys,

 

Following the recent debacle about the drawings in the ‘Beginners’ series on the ‘Countryman’sSteam’ I made an offer to David to write an article or two on the basics of Technical and Engineering drawing for beginners as it is such a complex method of expressing ideas. I thought that it could perhaps be included in MEW. Unlike the recent CAD series, it would not have been about making drawings or designs but about interpreting and reading existing drawings – not easy if you are not familiar with the standard methods of representation.

 

Having taught the subjecti(including CAD and Graphic Design) when I was a teacher following my Engineering career I thought that I might have a bit of a contribution to make to those who haven’t had the benefit of learning about BS 308 etc and thought that beginners might like to be able to interpret drawings properly. I know that BS308 has been superseded by ISO standards but many of the drawings we encounter were (and still are) drawn to those British Standards.

 

I am sad to say that I had a less than enthusiastic answer to my offer. i.e.

 

“Hi Terry

Readers don’t like engineering drawing articles in ME or MEW, they want steam engines and tools.

I regards David”

 

I find this a bit of a personal insult given that over the last year or so we have had many articles about 3D and 2D CAD systems which were of little interest to myself, not to mention a (poorly designed) woodworkers bench and articles about woodworking tools etc etc. I would have thought that basic technical drawing interpretation was essential in our hobby to make those steam engines not just draw them which the CAD articles was all about.

 

Is it one law for one set of contributors and another for others if your face doesn’t fit. Should I change my name perhaps to D Fenner the 2nd or something similar and then get any old article published.

 

I’m also sorry to say that David’s reply inferred that we are only interested in (quote) “Steam Engines and Tools“. How about clocks, i.c, engines, model machines, and all the other subjects we may model. Does David’s comment reflect current editorial policy? If so I’m saddened after many years of reading both magazines the idea of Experimental Engineering etc seems to have been sacrificed to the God of the steam locomotive.

 

I would appreciate subscribers comments please. Am I really so wrong?

 

Best regards

 

Terry

 

Edited By Terryd on 17/04/2011 21:52:49

[TerrydParticipant @terryd72465]

[Les Jones 1Participant @lesjones1]

Hi Terry,

I also think it would be a good choice for a series of articles as it deals with the problem from both ends. It would help improve the standard of drawings presented for publication and it would help readers with understanding the conventions used. There could be no better evidence for this then the thread you mention where no one on this forum can work out what the drawing means.

 

Les.

[TerrydParticipant @terryd72465]

Hi Gaham,

 

Thanks for that vote, I was beginning to think that I was some kind of a lonely dinosaur in these matters,

 

Best regards

 

Terry

[Ramon WilsonParticipant @ramonwilson3]

Hi Terry,

 

I must admit I’m surprised at the reply as like Gray I would have thought there was, indeed should be, room for such information.

 

Gray’s coment regarding the ‘It will do’ syndrome is I’m afraid growing apace at an exponential rate in all walks of life. I regret to say I have long given up trying to fight against it and just do the best I can to ignore it as it certainly isn’t going to improve – well not in my life time I’m sure.

 

For years model engineering drawings have been produced – and accepted as such – to varying standards. My personal niggle is the double or multiple datums but thats another story and one for which someone leapt down my throat the last time it was raised but when the true beginner gets faced with such a drawing with no background with which to eliminate potential minor machining disasters caused by such misleading information it can, and indeed probably does, lead to uneccessary anguish and particularly to the novice (though not always so ).

That said however I appreciate only too well that many of our contributors have no background in drawing skills – I’m one myself – currently well into an article and spending a fair amount of time trying to produce a set of drawings using recently acquired CAD skills to accompany it rather than provide the pencil produced drafts that I originally worked from.

 

To my mind then such an article could do nothing else but help those in early days of machining so it seems to me that your offer, aimed at the audience you refer to, is a sensible one that perhaps will hopefully be reconsidered.

 

What is it about one volunteer and ten pressed men?

 

 

Regards – Ramon

 

 

 

 

 

 

 

Edited By Ramon Wilson on 17/04/2011 23:27:36

Edited By Ramon Wilson on 17/04/2011 23:43:13

[TSHParticipant @tsh73987]

Terry,

 

What an excellent idea. The last formal teaching I’ve had on this was in “technical drawing” at school (which I enjoyed). I find it a bit of a struggle to follow even relatively simple published drawings and have all but given up trying to use a 2D CAD program—I simply don’t know the terminology. I feel that learning about the standard conventions in use would help with both these.

Go for it! (If you can swing it.)

 

Regards,

 

Trevor

[Steve GarnettParticipant @stevegarnett62550]

Interesting question, that. I can see plenty of beginners having a little difficulty with interpreting drawings, certainly at the outset of their modelling careers. And also, IIRC it’s not something that MEW has ever covered before. Is it just because of a perception that it wouldn’t go down well, or is there some real evidence?

 

Over the years there have been plenty of articles, certainly in MEW, that haven’t purported to be about making anything in particular, and they have been extremely useful – there are all sorts of things that I now know rather more about than I did before because of them. And on that basis, I don’t see why at least one article about drawings, and interpreting them, would go amiss at all. Especially as it would help to address the few complaints that keep cropping up about not enough articles aimed at beginners, wouldn’t it?

 

So just as a matter of principle, it would get my vote too.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Terry, I first learnt TD at school and next to metelwork was my favarite subject, and while I understand TD’s fairly well I believe, I couldn’t tell you if it was BS 308 or not, as I’ve never really had to know that.

 

When I was at colege on my C&G welding courses we did TD at a more advanced level (as you would expect) and when into the technitions course even more intense. But this was when the ISO standards were becoming more of a standard in industry, and all before PC’s let alone CAD existed. I do have a simple to use CAD programe, but I am not fully coversant with doing CAD in general.

 

While CAD has undoubtable advanced TD, you still need basic knowledge of drawings to undetrstand them, and I think the ability to do TD traditionally would go a long way to understand CAD drawings.

 

While learning at school and coledge, freehand sketching and the use of TD equipment to produce isometric views was also included in the subject. While on my C&G courses the geometry of sheet metal work was part of the subject also, as the need to develope things like cones and ducting interceptions needed to be understood.

 

Even now I don’t pretend to know everything about TD and I sure those who know very little would be interested to learn some basic hands on knowledge of it, using such things as Tee and Set squares and the like. Model Engineering is not just about bulding models. How many people have though of taking it up, but dismissed it because they don’t know what the drawings mean?

 

Regards Nick.

 

Edited By Nicholas Farr on 17/04/2011 23:48:50

[Steve GarnettParticipant @stevegarnett62550]

7-0 so far…

[AndyPParticipant @andyp13730]

Terry,

 

Excellent idea that I would find very useful. I have only been at this for 5 years so count myself as a beginner, got as far as an air running Rob Roy, sometimes despite the “words and music”.

First and third angle projection has never been intuitive to me having a background in civil engineering.

If the article covered the styles of some of the major contributors in the past that would be great.

 

Andy

[Bob LambParticipant @boblamb44747]

Hi Terry – I also would be very interested in an article on drawings. It is many years since I did any seriously and I feel any help to make the drawings show what is actually there can only be helpful. I do hope David can find space as I’m sure it would help a lot of people.

 

Hope to see it soon,

 

Bob

[TerrydParticipant @terryd72465]

Posted by Steve Garnett on 17/04/2011 23:41:14:

7-0 so far…

 

Thanks for the comment Steve,

 

I am quite surprised at the response within a couple of hours, it seems as though there might be a demand for such a useful series for many readers than some articles we have seen in the magazines recently,

 

Best regards

 

Terry

[Sam StonesParticipant @samstones42903]

Further to Terry’s and other postings, how about a little test?

 

If you already know the answer, please keep it to yourself for a few days. If you don’t know the answer and can’t work it out either, then post a reply to that effect.

 

The test is simple, but is intended to help to determine if Terry’s idea is a popular one.

 

The two views (FRONT and PLAN), are drawn in first angle (English) projection (not third angle). Tutt Tutt Sam!!!

 

There are no missing lines on either of the views shown, neither full lines nor dotted (dashed). With your knowledge of engineering drawing can you construct the side elevation (above the word `SIDE’)?

 

By the way, although I worked out the answer at secondary school when I was thirteen, have also been `doing’ engineering drawing since about 1948, and have taught various levels of engineering drawing (mainly applied to other subjects), I have no idea what BS 308 looks like. Another Tutt Tutt.

 

Regards to all,

 

Sam

[_Paul_Participant @_paul_]

“Hi Terry

Readers don’t like engineering drawing articles in ME or MEW, they want steam engines and tools.

I regards David”

As a reader I would dispute the above…

 

I for one would welcome a series on drawing interpretation.

 

No matter how much one thinks one knows there is always something new to learn.

 

Regards

 

Paul

[adyParticipant @ady]

There are no missing lines on either of the views shown, neither full
lines nor dotted (dashed). With your knowledge of engineering drawing
can you construct the side elevation (above the word `SIDE’)?

 

Is it two box shapes with curvy sides between them kinda thing…the apex of the curve being the middle box…?

 

uh…I think my brain just melted….

Edited By ady on 18/04/2011 03:51:36

[Richard ParsonsParticipant @richardparsons61721]

Oh not that hoary old chestnut.

 

I was shown that long ago.

It is a good laugh

Dick

[JasonBModerator @jasonb]

As one who picks up these errors just casually reading through the articles let alone building the actual model I feel it is a very good idea. Most people comming into the hobby under the age of 40 will not have done technical drawing as a subject at school and maybe only TD rather than metalwork ( or “engineering theory & practice” the O level equivalent) and will not have been tought how to read a drawing.

 

On several occasions I have been PM’d by novice/beginners with queries on drawings, they often say they don’t want to ask simple questions on the forum and look silly. Mostly its the drawing or just how things are shown that they don’t understand rather than an outright error.

 

As for Davids comment, maybe he should have asked through this forum if it was felt this type of article was needed. He’s a fine one to talk – regarding the Countrymans article when he was sure the odd item was the spokes and the amount of time it took for anyone to accept there were errors in the Northumbrian frame drawing.

 

The odd error or missed dimension is bound to slip through but to have so many on just one drawing is not really acceptable.

 

I’d rather see a drawing article than file handles, aeroplane weather vanes and even the trams are more railway modeling than ME.

 

Jason

[Sam StonesParticipant @samstones42903]

Frayed so, Dick.

 

Most of my nuts are old and hoary.

 

But, I’ll bet it wasn’t 1948 when you were shown it. You couldn’t be that old!?

 

ady, You could be on to it !

 

Sam

Edited By Sam Stones on 18/04/2011 08:41:44

[Eric CoxParticipant @ericcox50497]

Judging by the number of incorrectly dimensioned component drawings in articles, I would have thought an article of this type would be most welcome.

 

It should be realised that TD is an engineering skill and not something done on the back of a fag packet.

[KWILParticipant @kwil]

As someone who was trained in the art, I agree that something has to be done to improve the standards of submitted work and also to aid those who have not had the benefit of training and/or experience. Go for it Terry (AND David)

[Nicholas FarrParticipant @nicholasfarr14254]

Posted by Eric Cox on 18/04/2011 09:31:11:

Judging by the number……………………..

 

It should be realised that TD is an engineering skill and not something done on the back of a fag packet.

 

 

Wot!

 

Hi Eric, all the best ones were done on fag packets, it all depended on which brand the draugths-man smoked, and at least you could argue that it wasn’t your fault if it went pear shaped.

 

Hi Sam, I haven’t seen your test before. Is it a trick question?

 

Regards Nick.

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

I once had an in exhibition discussion with a long past editor and the subject of writing articles came up . When I suggested a series of short articles based on bits and pieces of real engineering practice I was told that :

 

‘ Model Engineering has nothing to do with full size engineering and readers would have no interest on any articles of this sort , In any case we already have many great experts that can cover all aspects of Model Engineering and I doubt whether there is anything to learn from the cruder engineering practiced in full size ‘

[Steve GarnettParticipant @stevegarnett62550]

Posted by Sam Stones on 18/04/2011 08:36:29:

ady, You could be on to it !

 

Hmm…. I think that ady has just made Terryd’s case for him entirely!

 

Hoary old chestnut it may be, but it still has its uses, eh?

 

And Michael seems to have come up with some evidence (at least anecdotal) that this may well be perceived wisdom, and not anything real. 

Edited By Steve Garnett on 18/04/2011 10:12:25

[Bill StarlingParticipant @billstarling10428]

Dear Terry,

I’ve only just seen
this thread. Yes please, an article(s) on technical drawings would be
an excellent idea.

I remember some cryptic
comments from one of the expert tutors on the SMEE training course
about model engineers’ drawings, where dimensions had no common
reference point. On the other hand ‘proper’ engineers’ drawings gave
dimensions from a fixed datum.

Am I alone in thinking
that model engineering is more than just making things, whether steam
engines, aeroplanes or even trams? For me it includes studying the
history and development of technology and techniques.

In many ways the Model
Engineer magazines of the 1950s and 60s were more interesting than
those of today. The contributors seemed to have greater practical
experience of the subject – yes, I do realise it’s not so available
today. Also the articles were more wide ranging and aimed at
producing models using basic equipment and skills. Personally I don’t
want a computer to drive my machining centre, I may as well buy a
finished product.

Never the less I really
appreciate the constructive contributions to this forum, especially
those with photos – and drawings!

Bill.

[Steve GarnettParticipant @stevegarnett62550]

Posted by Bill Starling on 18/04/2011 10:22:06:

I remember some cryptic comments from one of the expert tutors on the SMEE training course about model engineers’ drawings, where dimensions had no common reference point. On the other hand ‘proper’ engineers’ drawings gave dimensions from a fixed datum.

 

You might like to read through page two of this thread, where it is discussed, and what I hope is a realistic point of view is advanced – because it’s by no means as clear as has been expressed by some commentators, certainly when it comes to actually machining parts. And, in the relevant BS standard, variations on dimensioning schemes are allowed for precisely this reason.

 

And having just read through it again, I’d say read the entire thread. It is particularly relevant to this issue, and explains rather well why I agree very much with Terryd’s idea of an article, and just how damned relevant it would be.

Edited By Steve Garnett on 18/04/2011 10:49:12

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