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RE: Re: Structural Engineering as Art

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-----Original Message-----
From: Richard Lewis [mailto:rlewis(--nospam--at)techteam.org]
Sent: Monday, January 04, 1999 6:30 PM
To: seaint(--nospam--at)seaint.org
Cc: seaint(--nospam--at)seaint.org
Subject: Re: Re: Structural Engineering as Art
"Dennis,

I think you are a bit bias towards use of computers, and it shows by your
comments.  I have been watching this discussion from afar and I just can't
stay out any longer.  I do not think, or at least I did not take it that way
from Mr.. Ketchum's original post, that he thinks we should be using hand
sketches instead of computers.  Maybe he could correct me if I am wrong.  The
way I took it was that we need to think before drawing the solutions and look
at the big picture.  At least that is how I took it.  I am a big proponent of
the use of CAD.  I do 100% of my production drawings on CAD.  But I make many
sketches to think through what it is that I will eventually do on CAD.  The
main reason is for speed
For brainstorming it is a lot quicker to get some
1/8" grid paper, trace paper and sketch sections close to scale, rather than
putting in exact dimensions at a computer. 
I can then erase, scribble or
trash as I think it through.  But it is invaluable to sketch something out
rather than just think about it in my mind. "



Richard,
We don't disagree. You and Michael have labeled me as biased because I support electronic sketching and drafting. Yet you define the process the exact same way I have in my posts. The only difference is the instrument. You associate sketching with paper and eraser for speed. I associate my cad techniques the same way - much faster than manual sketching. This may not be true of everyone, but it certainly is of me. I can create a sketch ready for insertion into my final drawing from concept to finish much faster than I can by hand. But then again, I can also type over 80 words per minute and fine writing with a pencil or pen too tedious. In my case, I can think through my fingers and tend to make many mistakes as my thoughts come faster than I can write or print by hand. I can type as fast as my thoughts and not think about the process.

I associate it with a cad and editing functions - erase. You need to erase and redraw while I can simply move and copy. You draw lines, I draw with lines, circles and curves. You need a scale to be accurate, I only need to set the dimension variables. You use a pencil, I use a mouse, stylus, touchpad or whatever I have available.  If I wish to be mobile, I simply open my laptop and start to communicate. When the rare occasion occurs that I don't have it with me, I will gladly resort to paper and pencil (even pen).

The philosophy of thinking through the conceptual process is still the same - exactly the same unless you can show me the difference.

" As you stated above the computer
is very accurate.  And I am a stickler for accuracy on CAD.  I hate it when
people do not drawing objects in CAD to actual sizes.  But for the thinking
process exact sizes are not required and a sketch pad will suffice and
usually be more cost productive.  I think this philosophy is still relevant
for the current time."

I strongly disagree with you on this issue. First and foremost, I never use a cad without strict adherence to dimensional accuracy - this is the main advantage to using the tool. To ignore it is no better than sketching without a scale at hand. There is no advantage or disadvantage to working in dimensionless scale. Dimensional sketching is simply a no-brainer when working in cad and therefore adds a much greater degree of accuracy without the loss of time.

Are you sure that your steel reinforcing fits into the masonry cavity? Without Cad this space is deceptive and what you specify on the sketch may be improperly finalized by your draftsman. I was recently asked by an expert witness to use a cad package to drawing the true diameter of the rebar and dimension of the concrete column. It quickly became evident that the engineer specified too much steel in the column and that it would not all properly fit including the vertical ties. The engineer who designed the column reinforcement was being sued for failure of the columns. This type of inaccuracy is too easy to pass along to the production team.

I can't tell you how many times I have received sketches for associates who I've shared work with that provide me with sketches that turn out impossible to construct. Why waste valuable conceptual time if the detail ends up useless because the rebar ends up too tightly packed or the shear transfer can not work in the manner represented.

"I guess I come at this bias based on my experience with a previous employer.
I worked for a brilliant engineer.  I really admire his talent.  I used to go
into his office and ask him questions about the design I was proposing.  His
first response was always "have you cut a section through there yet?  Let me
see it."  All too often I would have to say no and go back and do it.
Usually the answer would pop out at me while I was sketching it."
 

The same answer "pops out" when drawing the section using a cad tool. The argument is not the tool but the repose - the timeout to leisurely sketch the true condition and work through the design process using objective thought. So where is the difference? If you wish to save time, I suggest the cad program which often can cut the section automatically rather than to rebuild it from scratch.


The design steps are always the same - Cad or Manual sketching does not change this. Only the tools are different. A skilled user of each technique can make the most productive each. The second difference is that once I have worked out the solution, I can simply paste it into my detail page and add a few notes - something you can not do with a sketch unless you pay as close attention to the accuracy.

I think that there is a bias to manual sketching. I believe the bias is that it is a time honored and respected art form deserving of protection from change. The problem is that older engineers (I am about 50) consider new tools such as cad as being "artless". They consider all cad drawings to look alike - and without the romanticism of the past.
This can not be farther from the truth as Cad can and often does imitate art. The results from a skilled user of the software can create a drawing which would fool most into thinking it was done by hand.

"I think, at least that is how I took it, that this idea of sketching is what Mr. Ketchum
was referring to.  Unfortunately I do not have his original post to verify
it."

And I believe it was because he did not have an alternative. Most technicians love technical advancements. I remember visiting H. B. Daniel's in Los Angeles and looking forward to purchasing new drafting instruments. At the time, producing a drawing by hand was a very special process that I took great pride in. A few years later, I did not want to go back to manual drafting. In the process, I began to see Cad as a challenge. first I wanted to create a drawing that was indistinguishable from hand methods. Then I wanted to use fonts and lineweights to improve my presentation. Then it was hatching and shading to further enhance my package.

I guess I was hanging on to the "artistic concept of drafting carried down for hundreds if not thousands of years". The realization is that Cad offers the same challenges - the ability to create a personal, unique package that would be recognized as your work. The main advantage of cad was that I did not need to focus on lettering and lineweights any longer, but could seriously think about sheet layout and presentation - a very neglected form of the art.

I have reviewed many packages by others. The majority of engineers that I have plan-checked (a part-time venture) do not pay attention to their package, nor are the concerned with presentation. The one thing that sets you and Michael and I off from these whom I've checked is our desire to either embrace the art or improve upon it. This is a great tribute to pay to our field.

I guess I'll end the argument with this. I admire anyone who is willing to take the time to insure that he devotes sufficient time to the creation of a solution and to the presentation of his or her work. This is exemplary of those of us who have a great respect for the profession and the art of design. The instrument of our efforts does not matter in the least - only the ability to recognize the creativity we try to communicate with and to use it effectively. In this respect, a pencil is as convincing as a Cad.


The next time you sit down to work out your problem on sketch paper, think of me doing the same process and ask yourself if there is anything that you are doing with a pencil that I can not do by a computer program. I'll be doing the same.

In respect to the others on this list, I would be very happy to take this discussion private if you can to continue. I think I have said all I can in the defense of the medium unless you enjoy the debate as much as I have.

Regards
Dennis