Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Level of Detailing

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Very well stated Michael.


On 8/21/06, Michael Hemstad <mhemstad(--nospam--at)> wrote:
As noted by Dave below, and also by Daryl and Chris, there are a lot of reasons why drawings are noted as "Do Not Scale."  We try very hard to draw everything to scale, the first time.  But two things happen:  some of the details are typical of several areas, and thus can't be to scale; and some of the details get changed as the drawings progress.  I make no apologies for the first; and not much for the second, as we do not have the endless fee needed to make perfect drawings twice  ;<)     In fairness, we try very hard to make everything to scale, often more than once; but sometimes toward the end of difficult jobs human nature gets in the way.  I have worked with technicians, excellent technicians, who refused to make drawings not to scale with a religious fervor.  They made very good drawings, and their jobs were always over budget.   Will Haynes' snootiness is not appropriate; the architect and his indecision is usually the reason for drawings not being to scale, and our drawings are usually more to scale than theirs.  And if we want to split hairs, any detail with break lines is NTS.  Ever use break lines in your wall sections, Will?
As Daryl notes, the printing process used to result in rather a lot of dimensional instability in the plan paper.  The xerographic reproduction now used itself causes less distortion, but the paper is still subject to dimensional changes due to changes in ambient humidity.
I found this thread amusing, as I just bought scales for the EIT and Intern who kept borrowing mine.  They are happy to use them; the paperless office is still just a pipe dream, especially on retrofit and rehab work.  Nice crisp edges on those new scales....
We routinely scale drawings for design, as it is quicker and typically accurate enough; but it's not something you want to do with your eyes closed.  For instance, dedicated sections might be safe, but anything that's supposed to cover more than one situation (especially any detail cut with a SIM) is dangerous to scale.  Plans are usually safer to scale than details.  Every four or five dimensions, I try to verify what I've just scaled.  It turns out to be an excellent form of quality control on the drawings.  If I don't have the information to design it, the contractor probably can't build it.  We frown on contractors scaling drawings primarily as a quality control measure.  If we missed dimensions on our drawings, we want to know about it so we can fix it; if we changed dimensions on our drawings without re-drawing it, then we really don't want anyone scaling it.
Mike Hemstad, P.E.
Minneapolis, Minnesota
Dave Lowen wrote:
I spent a little time doing an informal survey of estimators, PM's,
draftsmen, shop and field people and found that about one in six owned a
scale. Most of the younger people had never bought one. Some of the folks
that owned one said they seldom used it, some said they never did, one said
his is in a drawer somewhere at home.
One of the reasons I was given for this is that although a majority of
architects and engineers specify scales on every plan, view, section and
detail, there is also a covering note that the drawings are not to be
scaled. I would suggest those that practice this to not waste money putting
the scale on the drawings.
Another reason is that many people who use your drawings have new furniture
that does not lend itself to the massive drawing sizes some firms use so
they have them plotted no larger than 24 x 36 which makes the scale
My work is initially drawn to scale as Will suggests but all drawings are
noted "do not scale". My reason for doing this is to cover any subsequent
changes where only the dimensions and not the picture are changed. This is
not laziness on my part, it is economics.
Dave Lowen
V 519 587 5797
F 519 587 5138
E jatech(--nospam--at)
-----Original Message-----
From: Will Haynes <
gtg740p(--nospam--at) >
Date: 2006/08/12 Sat PM 02:02:11 CDT
Subject: Re: Level of Detailing
As an Architect and builder, I see absolutely no reason why every aspect of
a structural design isn't drawn to scale. IMO its pure laziness that
details are drawn NTS. With the sophistication of CAD programs today, there
is no excuse for not drawing to scale.