Jump to content
howitzer

Survey: How important is linework accuracy?

Recommended Posts

I'm interested in what others do and/or think, wondering if I'm on track, or whacked out.

 

How important is it that linework be accurate? By accurate I mean, lines that are supposed to be parallel are indeed parallel, not a couple seconds off... two lines that are supposed to meet at their endpoints, do indeed meet at their endpoints, not overlap... things like that.

 

My position is, or has evolved to be, that you save yourself so much time and trouble and heartache in the long run if you're accurate from the very beginning. It's easier to do it right from the start than it is to do it wrong then make it look right, especially where dynamic labeling is concerned. Even if it ostensibly 'doesn't matter because it won't be built that close anyway'. If I'm laying out a sidewalk, for example, I expect the sides of the sidewalk to be parallel. I expect lines/arcs to be tangent (excepting the rare scenario where you have no choice for whatever reason).

 

Others in my firm do not believe I should be so dogmatic about it, that there are times where it's just wasting time for something that will never matter. Yet, in my experience, my rear end has been saved from blame because my linework was accurate. If nothing else, there's potential liability reasons.

 

Your thoughts?

Share this post


Link to post
Share on other sites

To me it is actually easier and quicker to do things accurately, and it looks so much nicer. From the stand point of getting something like a sidewalk built it probably doesn't matter, but I can't bring myself to "sketch" with CAD.

Share this post


Link to post
Share on other sites

Your listed as CIVIL so with GPS setouts, 3d machine control accuracy is becoming more important. Its so easy to do it correct using snap and ortho to say it does not matter is not the sign of a good designer.

Share this post


Link to post
Share on other sites

I probably spend half my time making other peoples drawings accurate, I have to take off quantities from drawings supplied by others, and it is so much easier to do that if polylines are closed and not made up of overlapping objects, it's a fairly simple formula to find the length and width of a wall given perimeter and area, but only if that information is accurate. For a 160 apartment tower block, it can take me nearly a week to clean up the drawings and get things on sensible layers. It is then just a question of days to take off the quantities and create the schedules, doing all that normally is 3 to 4 weeks.

And by far the best drawings, in general, come from the structural engineers, that's just a question of checking for odd errors. Drawings from Architects, that's just hoping that you can find a few that are straight. I think many of the errors are due to how "other" programs are converted to dwg.

Share this post


Link to post
Share on other sites

It's too easy to draw it accurate and correct to accept anything less. Like rkent, I see no reason to sketch with AutoCAD.

 

I fix any and all drawings I get or come across with inaccurate CAD work, if I am to work in them, if someone just wants something printed, I rarely bother to check it over for such things unless it just doesn't look right. Like steven-g, I find some programs convert poorly to dwg.

Share this post


Link to post
Share on other sites

It's been my experience that, once an error creeps in, it will get carried through everything that connects with it. An architect will use fractional units and believe that getting within 1/4" is close enough. In other words, he'd never see a difference as large as .12. After a few more near misses, each one amplifying the ones before, he'd wonder why his stuff wasn't lining up properly.

 

As SLW210 says, there's no excuse for doing it wrong when you have the tools to do it right. The people who will use your drawings are expected to work within certain tolerances. You owe it to them, and everyone else, to do the same.

Share this post


Link to post
Share on other sites

Accuracy is paramount in the world of design. Anyone who tells you otherwise should be doing something else.

 

A defect in a measuring device used to polish the mirror for the $1.5 billion Hubbell telescope made it virtually useless. It took a second mission (and additional monies) to fix the problem.

Share this post


Link to post
Share on other sites

I thought the ease of drawing accurately was one of the benefits of using a computer aided drafting program. If you don't want accuracy, use a pencil.

Share this post


Link to post
Share on other sites

Thank you all for your replies. It sounds like we're all pretty much on the same page... no pun intended.

 

I like the word 'sketch' for what I am describing. I think that's highly descriptive. The way I portrayed it is that, if accuracy isn't important, then we can buy some lesser program than AutoCAD and save a lot of money... but we don't, because accuracy IS important.

 

Turns out that I am not the only one who fixes things that aren't right when I get a drawing from someone else. Even if it's someone within my own company. If I get a drawing from an architect my mind is already conditioned to know that I will be reconstructing the majority of their drawing. I once had to trash literally an entire site layout once because not a single thing was accurate. Even the arcs for curb returns was just a series of short lines, all wildly inconsistent in length, that looked fine in a plot on paper, but served no useful purpose whatsoever.

Share this post


Link to post
Share on other sites

My drawings are not accurate at all I even tell people don't use my drawings to confirm the distance or the size of some feature that may be on the drawing. Most of the time the drawings I get are vectored PDFs that I convert to DWG. Then I have to scale them up. Of course doing fire alarm drawings accuracy of the drawing is not the most important part it's showing where the devices are going and how many. I know it sounds strange but my drawings are only for a relationship between devices installed and to where they are going. Any thing that requires any accuracy I show in a typical or a detail with dimensions. Rule of thumb is not to have your thumb where the hammer is going to hit. Translated leave the hammer alone and don't hold nails.

Share this post


Link to post
Share on other sites

In my line of work, line work and Layer Management are crucial as we design and build here. We fab most of our own parts. I work for a modular building manufacturing

company. Our modules have to fit together both horizontal and vertical as we do a lot of 2 story schools. If parts don't line up and fit it costs the company both time and

money. It's always better to do it right the first time. Speaking for myself, My pet peeve is lines on top of lines.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×