Are you the engineer and the drafter? 3

[upjengnr04]

For those of you who work as a one man team or for very small firms (in particular structural guys/gals), do you perform CAD drafting for your work or do you sub that out? Or maybe you don't use CAD at all?

Just curious as to your approach. I have previously worked for a large firm and had dedicated drafters for our projects. There were not many opportunities to learn CAD as it relates to project documents so there was a lot of "on your own" learning that had to be done if you wanted to learn.

Thanks.

 

[JohnRBaker]

...he/she is making decisions that involve fitting components together, while preserving the function in a way that only an Engineer can comprehend.

I have to say that that pretty much describes precisely why CAD has become primarily a tool for engineers in what I'll continue to refer to as the 'discrete manufacturing' industry. It also reinforces the point that drawoh made about CAD users needing to make design decisions not to mention IRstuff and his comments about how the 3D CAD models are the foundation for most of the downstream analysis and avoidance of spatial or 'packaging' problems. And we mustn't overlook that in the 'mechanical' world, the vast majority of times, these same 3D CAD models will eventually be used to plan and produce the actual instructions for cutting and forming of metal, the injection of plastic, molding of materials, or the welding of fabrications as well as the final assembly, testing and even the servicing of the final product. When, as is the case in our 'mechanical' world, so much depends on the accuracy of the model, both in terms of size and shape, but also its functional behavior, the more that it makes sense that these 3D Models be the responsibility of those individuals who actually know not only the 'what' but also the 'why' and 'how' of what is being produced, i.e. the engineering professionals, in their various disciplines, which eventually makes up the enterprise.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[AELLC]

John

I was looking at your website- is it saying that CAD had it roots way back in McDonnell Automation Corporation (something like that) - their facility in St Louis next to Lambert field? The same McDonnell as in Phantom F4 jets?

 

[KENAT]

Yes that would be the same McDonnell.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[AELLC]

LOL, small world.

 

[KENAT]

Just noticed "the vast majority of times, these same 3D CAD models will eventually be used to plan and produce the actual instructions for cutting and forming of metal" I think vast majority of times may be overstating things a little - though I suppose it depends if you are measuring discrete number of different parts or total number of parts...

Don't get me wrong, it's getting there and we're sending models alongside our drawings almost by default these days but there are still parts and vendors etc. where this isnt' the case.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[JohnRBaker]

Yes, the history of CAD, at least as it applies to our 'mechanical' world, owes it heritage to some early public R&D money which was invested in the Aerospace segment of the industry (although to be completely honest GM was an early participant as well, but then at the time GM was a significant supplier of propeller systems for commercial turboprop-driven aircraft) via grants from the DOD and the National Academy of Science. This money, along with some cash and hardware from people like IBM and some work being done at universities, was how CAD and this idea of 3D Models representing the core 'math' which defined a product, at least from a dimensional size and shape point view, was born. From that early research several companies and/or products were spawned some of which are still around if for nothing more than providing some of the 'DNA' which can be found in the mainstream CAD/CAE/CAM products in use today, including our own products, of which NX, our high-end full-function CAX system, is but one of them. In the case of NX, if the 'website' that you were referring to was that last link in my 'signature', you will see that ITS 'DNA' goes back over 50 years, to 1963 and a now totally forgotten little company named 'United Computing', which was one of the true pioneers in bringing affordable computerized manufacturing, i.e CAM tools, to, at the time, primarily the aerospace industry, actually to the small to mid-sized suppliers to the larger aerospace OEM's which already had their own in-house developed CAM systems.

Yes, the history of CAD/CAE/CAM goes back a lot further than many people realize, something that generally is only appreciated by those of us who have been involved in it for a significant portion of that period (my personal experience with CAD will be coming-up on 37 years this August).

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[beej67]

Gone are the days when "the guy at the drafting board" could actually lay something out once, revise it once, and have the engineer stamp and issue it. The proliferation of CADD and CADD-based designers since 1983 has actually increased net INEFFICIENCY by an amount measured in orders of magnitude, rather than mere percentage.

This is not true at all for civil-site, in my experience. In a properly run medium to large civil site shop, the PE of record will instruct his team of "designers" (not draftsmen, designers) in how he wants elements laid out, what he wants things to look like, etc, with some general comments on how certain constraining elements of the job are to be handled, and turns the designers loose in the CAD / CAE environment, then checks on them periodically to make sure they're all on the right course, all the while educating his designers on elements of the design they may not be familiar with. The PE reviews everything, may make more design changes himself, oversees the project to completion, stamps it, and it's done.

The designer talent for an operation like that is typically a bunch of EITs, with a few younger PEs or older draftsmen-turned-designers sprinkled in.

That's the best way to work it in my experience. If you're too small to have a pool of techs that are that sharp, then the PE has to be able to draft, and in my field that drafting has to be done in a CAD environment or you're flat dead in the water.

AELLC, you say it took you a week to do a sheet of structural details by CAD. You also said something about drawing each line individually. I don't mean any offense, as I'm sure you probably realize this, but that really just speaks to how poor your CAD skills are. A detail sheet from scratch for me would take a day tops. If you ever get stuck doing that again, I suggest you learn the modfiy commands (offset, copy, rotate, mirror), you learn the osnaps, and you learn the keystroke shortcuts. Everything in the AutoCAD environment is built to make drafting go faster, you just have to learn the environment.

Or, if you're an old fart, hire someone who's already learned it I guess.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -

http://www.campbellcivil.com

 

[JohnRBaker]

...I think vast majority of times may be overstating things a little -

You're correct, that was a bit of a generalization, and it does vary depend on the industry segment with probably automotive and aerospace being where the most progress has been made with respect to this (at GM it's called the 'single math model' approach). However, there are other examples as well, particularly with some of the relatively newer enterprises, such as Apple for example (I made my first sales call to Apple when they had just released the Apple III and they even 'loaned' our San Jose office an early Lisa which we had no end of fun playing with at the time) which has been working the full 'art-to-part' paradigm almost from their first use of CAD (our's of course). And now with the proliferation of 3D Printing systems, another technology which has been around at lot longer than most people realize (I was the Product Manager on our first 'Rapid-Prototyping' interface module back around 1991-92), the need for an accurate 3D model is paramount.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[AELLC]

All I can remember, I was drafting by hand about 1970-1972, and all I can remember is seeing a lot of IBM360's in another large building, mostly churning business data for other clients.

However, in one of the classified areas there at McDonnell-Douglas Corp, I saw, on a CRT computer display, a 3D (stickframe) model of the engine inlets of an F4, all of which I am sure I was not on need-to-know basis on that topic.

They had 2 or 3 levels of security clearance at the time and it was some tour where they showed us only the stuff we were cleared for.

 

[AELLC]

beej67.
No offense . I have severe dyslexia and that was a significant problem. It gets worse with age too.

 

[AELLC]

I took the basic intro to CAD about 15 yrs ago, but the teacher was not good. I then dinked around with it occasionally, but really only needed to view and plot for my business reasons.

The clients I deal with all do my struct drafting, and they all know my system, and they never screw up more than once.

In fact, when I get a new client, I tell them they have to use my details, my schedules and notes, or I wont do biz with them.

 

[JohnRBaker]

...at McDonnell-Douglas Corp, I saw, on a CRT computer display, a 3D (stickframe) model of the engine inlets of an F4...

What you saw was most likely a terminal running CADD, MDC's internally developed 3D CAD system. It probably looked something like this with people using light-pens to make selections on the screen and a PFK (Pushbutton Function Keyboard) to make menu selections:

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[debodine]

I have reasonably developed ACAD and SolidWorks skills (not a master of either). I will never claim that this abilty makes me a better engineer. I will state that for me personally it makes me a more efficient engineer in that I can do two things faster than in the old days when I submitted sketches to competent drafters:

1. I can sketch out and ponder multiple designs that will be easier and more accurate to review for form, fit, function, interfacing (a BIG plus) and interference than when I did all sketches by hand. The CAD programs give me the ability to reject options more quickly and focus in on what works.

2. When creating the final product, I can make the changes much more quickly the way I envision them rather than trying to communicate them to another person via markups, paragraphs or face to face conversations.

Again, none of the above makes me a better engineer, or by itself even a profitable engineer. But the CAD products help me do a better job of getting a design finalized and transferred from my mind to a reproducible drawing.

 

[wadavis]

I've worked for a couple small firms doing design drafting or design and working with a drafter, handing off the end result to the engineer/owner for review and stamping.

The highlight of my brief career was after our drafter quit and we outsourced the drafting to a semi-retired professional drafter. I'm finding it hard to describe how great it was, we sent out a thorough sketch and our expectations along with a library of past projects for reference, and we got back a complete drawing set that looked like it was done ourselves. Red lines were corrected on the first try and on top of that the same mistake was not repeated on the next project.

Some of the bad stretches included trying to train new drafting staff (to draft and our industry) while doing design, in the end putting them on make-work projects while I did the drafting myself to meet the timelines.

And somewhere in the middle falls the time I've worked without drafting support and did it all myself, this had the huge downside that you are worrying about drafting when you should be designing, and worrying about designing when you should be drafting. All with the client deadline on the horizon and leaning on both the tasks you have on your plate.

To answer your question, having good help makes the difference, and even with acceptable help I consider it a huge accomplishment to have helped change my current office from a drafting designers environment to a drafters and designers environment.

 

[brandonbw]

I think you can be fast either way. I worked at a place that taught drafters how to design and were very efficient. I have worked at another where the drafters were completely awful. I prefer to do all my own drafting and help my partner out as he doesn't like to draft.

People who know how to hand draft can be more efficient when it comes time for the computer input, just need the proper training or tricks from the more experienced. I have seen very few things that can be hand drafted faster than in the computer. And that is why if someone is willing to pay I will turn a large project around in a day or so. Which we have done.

B+W Engineering and Design
Los Angeles Civil Engineer and Structural Engineer

http://bwengr.com

 

[berkshire]

brandonbw (Civil/Environmental)
I was one of those guys that started out as a tin-basher, I served a 5 year apprenticeship in the design and construction of heating and ventilating systems. I then went to a different company ( one of John Bakers Competitors.) who put me in their drawing office as a detail draughtsman,primarily because on my knowledge of flat pattern lay out and how ducting fittings should look on a "real Drawing". During this time I also got into structural detailing and machine detailing. This was in the late 1960s. I had a 20 year break while I went into the aircraft industry, then came back to drafting in the USA in the 1980s At this point I found that in the USA a draftsman simply puts lead on paper and does not do any of his own calculations, so I was upgraded to Designer. I felt that I was still a draughtsman. For many years I did paper and pencil drawings, then got into Auto Cad in about 1990. For years I felt that I could get a drawing done on the board on paper faster than Cad. Then I realized one day, that although I felt that way it was not true in practice, especially when it came to doing notes and bills of materials. I then went through several different companies all with their own cad systems Cad key 99, Inventor 4, Solid works 2001 through 2006 now to Geomagic design. During these times the Cad programs have gotten better at unfolding parts for shop fabrication. I am not an engineer, I have never claimed to be one, I am a designer. I have always worked with engineers to get drawings the way they want them , or to get a drawing to something that can be manufactured on the shop floor. I have had breaks outside the industry as a business owner and employer .
B.E.

You are judged not by what you know, but by what you can do.

 

[IRstuff]

In some respects, the people here are lucky to even have this subject to discuss. In EE-land, we used to have schematic capture and PC board layout designers. Both have essentially all but disappeared. Schematic capture is done by the EE himself, and board layout is mostly an automated process, where the only inputs are parts placement and layout constraints.

TTFN
faq731-376

Need help writing a question or understanding a reply? forum1529

 

[Nereth1]

In my current position, I engineer and draft more complex projects, while I engineer, handball to drafting, and then redline more simple stuff.

Once I tried to engineer something complex, and then send to drafting as I was massively overburdened with work - but I took it back 2 hours later when I realised how much stuff is in my head that doesn't get put into the final product that way without 3-4 time wasting review cycles ending up costing me more time than it saves. Haven't done it again since.