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CAD Forums => Vertically Challenged => Land Lubber / Geographically Positioned => Topic started by: Jeff H on January 24, 2012, 10:26:56 AM

Title: Why are Civil plans 17,000 miles from the orgin?
Post by: Jeff H on January 24, 2012, 10:26:56 AM
I am sure there is a reason and not familiar at all with civil work flow, but it seems every site plan I get is a whole state away from the orgin.
 
Just wondering.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on January 24, 2012, 10:33:47 AM
Because we use State Plane or other coordinate systems to align the work to it's actual location on the panet.
Unlike most Architectural plans, that are often tied to nothing in the real world, as is say 0,0,0.

This leads to some interesting discussions regarding each professions methods.

The Architects would be well served to base their actual site plan on the actual surveyed location.
Although some do, most wont, and that's all I'm going to say about it.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: alanjt on January 24, 2012, 10:35:27 AM
State Plane coordinates.
Since our drawings are in Florida North zone, I redefine the origin to match the coordinates, so hatch patterns (ar-conc) don't look out of wack.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Jeff H on January 24, 2012, 10:35:58 AM
Makes sense to me and does not really cause any more work and I am not fussing about it.
Was just wondering.
Thanks
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: alanjt on January 24, 2012, 10:44:19 AM
fussing about it.
Man Jeff, stop whining about it! :-P
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on January 24, 2012, 10:50:03 AM

Was just whimpering and whingeing about it.


Don't be such a little girl...   ;-)
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Krushert on January 24, 2012, 10:56:49 AM
This leads to some interesting discussions regarding each professions methods.

The Architects would be well served to base their actual site plan on the actual surveyed location.
Although some do, most wont, and that's all I'm going to say about it.

Yeah .............. right.  What ever you say. :roll:
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on January 24, 2012, 11:10:01 AM
This leads to some interesting discussions regarding each professions methods.

The Architects would be well served to base their actual site plan on the actual surveyed location.
Although some do, most wont, and that's all I'm going to say about it.

Yeah .............. right.  What ever you say. :roll:


Although some do, most wont, and that's all I'm going to say about it.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Jeff H on January 24, 2012, 11:42:08 AM
It's my thread and I bitch if I want to, bitch if I want to.
 
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: alanjt on January 24, 2012, 11:43:44 AM
It's my thread and I bitch if I want to, bitch if I want to.
You would bitch too...
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Slim© on January 24, 2012, 03:39:33 PM
Civil/Survey = REAL WORLD

Architects = Fantasy
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Krushert on January 24, 2012, 10:14:01 PM
Civil/Survey = REAL WORLD

Architects = Fantasy
Ahh lets put that to the test.  Lets take a dozen civilians off the street that know nothing about our trades and explain to them our layering name conventions.  See which convention gets understood first. :evil:
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Dinosaur on January 24, 2012, 10:22:52 PM
You will first have to explain to all of them why the artichokes have drawn everything 12x what it is supposed to be and warped the Earth's surface so North appears to always point to the top or left of the sheet regardless of the true position.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: alanjt on January 24, 2012, 10:25:18 PM
Civil/Survey = REAL WORLD

Architects = Fantasy
Ahh lets put that to the test.  Lets take a dozen civilians off the street that know nothing about our trades and explain to them our layering name conventions.  See which convention gets understood first. :evil:
I thought Architects just put everything on the "0" layer and changed the color. :P
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Dinosaur on January 24, 2012, 10:37:55 PM
I thought Architects just put everything on the "0" layer and changed the color. :P
Shhh ... my old boss probably still does that and he is a civil engineer / surveyor.  I used to threatened to take away his computer keys.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on January 25, 2012, 07:54:17 AM
Civil/Survey = REAL WORLD

Architects = Fantasy
Ahh lets put that to the test.  Lets take a dozen civilians off the street that know nothing about our trades and explain to them our layering name conventions.  See which convention gets understood first. :evil:
That would depend entirely on the organization, and or if they had bought in to the NOT NCS for their works.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Dent Cermak on January 28, 2012, 10:36:47 PM
It's more like:
Civil/Survey = Model Space
Architects = Paper Space.
And it's a REAL long streatch to laud Architectural layer name conventions. X-DES-GRD-FLR-BEM-REV1-LATTADOODOO?
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 06, 2012, 02:37:37 AM
All this banter is fun and all, but to get back to the original topic, here's something that may provide some useful information about the whole theory around using Grid Projections like State Plane or UTM:

http://www.ejsurveying.com/Articles/Working_with_Grid_Coordinates.pdf

The basic idea is that effects of "curvature of the Earth" and "elevation differential" get automatically corrected for, by using a Grid System with Floating Scale Factor.  This lets us pretend that we're in a straight Cartesian grid, even though we're Surveying on the surface of the Earth (a sphere where the ground level potentially changes by a lot, especially in mountainous areas).  Net result is that we can use simple trig in our calculations, and all the other details are abstracted out into the Grid Projection + Geoid Model, where the computer takes care of the grungy details.  (There are no Surveyors who are members of the Flat Earth Society - except maybe as a joke - because we can easily see the effects of Earth curvature in our every-day work...)
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Jeff H on February 06, 2012, 09:39:39 AM
Thanks Sinc,
 
That article helps to make sense of it all.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Birdy on February 06, 2012, 08:47:12 PM
This thread raises an issue that I have been pondering.  That is, AutoCAD's ability to accurately calculate points.  My understanding is that ACAD can accurately calculate to something like 14 significant digits. 

If your civil origin is at some predetermined municipal point on the map, and the clients house sits on a 5000 acre site, and is say, 45,000 square feet.  Said 'origin' may be rather far from the actual architects geometry.  Maybe a few miles, for arguments sake.  Now I come along to fabricate all the millwork in that house and I need accuracy to 0.1mm.  (Our CNC machines can achieve this quite easily I believe.)

If we all follow the origin started by the civil drawings, am I likely to run into problems with my drawings because I am relatively far away from (0,0,0)?

My question is, isn't it good cad practice to not draw so far away from the origin?  I'm not looking for an argument here, but an education.  :-)
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 06, 2012, 09:08:43 PM
Being distant form the origin typically only aggrieves autocad in trying to figure out hatch patterns.
This is due in part to how they are calculated.

Your mill work, and profiles for the Door Frames, and Chair Rails...would most likely be drawn as separate details.
These details would most likely be drawn from some arbitrary start point in a new file, or even at or near 0,0.

So the origin of the Civil coordinate system would have no impact on your millwork detail drawings.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 06, 2012, 09:12:11 PM
My question is, isn't it good cad practice to not draw so far away from the origin?  I'm not looking for an argument here, but an education.  :-)

The accuracy issue is important, that is why I think AutoCAD has insertion base INSBASE. As an architect I usually take the civic survey or base plan, save a copy to my working file, purge, color bylayer, etc, and set INSBASE to the lower left corner of the property line. Then I xref the plan with insertion point at 0,0,0. If I get an update from civil, I only have to fix INSBASE.

My building often has the same insertion point, or something logical like a grid line intersection, center of buiding, etc., though in the early design phase we may not know all those details and the propertly line is safer. The key is to keep a copy of the property line in my plan file so that there are no mistakes aligning the building on the site plan.

Dan
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 06, 2012, 09:20:42 PM
My question is, isn't it good cad practice to not draw so far away from the origin?  I'm not looking for an argument here, but an education.  :-)

The .......
Dan

All of the above is great, now tell him where you draw the details for the custom millwork.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Kerry on February 07, 2012, 03:48:11 AM

17,000 miles is about 3/4 the way around the world isn't it ?
... but if you've far enough North it could be next door.

... perhaps that demonstrates perfectly my ignorance of civil stuff.

 :lol:
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 07, 2012, 12:08:43 PM
All of the above is great, now tell him where you draw the details for the custom millwork.

That depends on how you set up your drawings. I draw all my details for a sheet in the same file, with viewports for each scale. We have a template with titleblock grids for all scales from FULL to 1/8", and the 1:1 scale has the left corner at 0,0

For elevations, I have 0,0 equal ELEV. 0'-0", so that I can just do an ID to check the height of something. The x direction usually is a grid, but not so important, just not 17,000 miles away...

Dan
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 07, 2012, 12:13:54 PM
All of the above is great, now tell him where you draw the details for the custom millwork.

That depends on how you set up your drawings. I draw all my details for a sheet in the same file, with viewports for each scale. We have a template with titleblock grids for all scales from FULL to 1/8", and the 1:1 scale has the left corner at 0,0

For elevations, I have 0,0 equal ELEV. 0'-0", so that I can just do an ID to check the height of something. The x direction usually is a grid, but not so important, just not 17,000 miles away...

Dan

As you stated earlier you MOVE the Civil Plans  to suit your practices.
So how I set up my drawings has no impact on where you draw your millwork details.
As you said, you start at 0,0.
Which is pretty much what I said happens.

So the answer to Jim H; is that the accuracy of autocad is generally not going to be an issue in regards his millwork.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 07, 2012, 12:19:11 PM
Which is pretty much what I said happens.

No disagreement, I was posting in response to Jim H's request for education/information.

Being distant form the origin typically only aggrieves autocad in trying to figure out hatch patterns.

This is easily fixed by setting SNAPBASE to a point near the hatch,  and updating the hatch geometry by HATCHEDIT. The hatch now has an internal relative origin near it and resolves correctly.

We do this all the time for custom tile patterns and controlling the start point.

Code - Auto/Visual Lisp: [Select]
  1. ;;; HatchTouch - Update selected hatch pattern start to current SNAPBASE point
  2. ;;;   (For realigning ceiling grids or brick modules, for example)
  3. (defun-q c:HATCHTOUCH ( / hn hs ha)                                                     ;
  4.   (princ "\nSelect hatches to TOUCH to update snapbase origin")
  5.   (if (setq ss1 (ssget ":L" '((0 . "HATCH"))))  ;only allow inserts on unlocked layers
  6.     (progn
  7.       (foreach e1 (xyz_sel2lst ss1)
  8.         (command "-hatchedit" e1 "properties" (XYZ_CMDACTIVE ""))
  9.       ) ;foreach
  10.     ) ;progn
  11.     (princ "\nNo hatches selected")
  12.   ) ;end if
  13.   (command "select" ss1 "")
  14.   (princ)
  15. )
  16. ;;;  (C.) 1996 by Vladimir Nesterovsky <vnestr@netvision.net.il>
  17. ;;; sel2lst is also on Reini Urban's site (see URL in the quotings).
  18. ;;; convert SELection set to LiST of e-names
  19. (defun-q xyz_sel2lst ( sel / l len )
  20.   (if (= 'PICKSET (type sel))
  21.     (repeat (setq len (sslength sel))
  22.       (setq len (1- len)
  23.             l   (cons (ssname sel len) l)
  24.       ) ;setq
  25.     ) ;repeat
  26.   ) ;if
  27. )
  28. ;==========================================================
  29. ; Continue pausing until exited command mode
  30. ; nil = pause
  31. ; otherwise pass string to use
  32. ;==========================================================
  33. (defun-q XYZ_CMDACTIVE ( passcmd / )
  34.   (if (null passcmd) (setq passcmd pause))
  35.   (while (not (= 0 (getvar "cmdactive")))
  36.     (command passcmd)
  37.   ) ;end while
  38. )
  39.  
  40.  
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 07, 2012, 12:23:52 PM
I'm aware of the problem (hatch Patterns) and the fix for same (SNAPBASE)

Someone might find that of use.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Birdy on February 07, 2012, 02:06:05 PM
So, being 17,000 miles away from the origin has little or no affect on my drawings accuracy, except for maybe hatches, which can easily be remedied?  Is that correct?

Also, what benefit is it to me to be 17,000 miles away just because the civil drawings are?
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 07, 2012, 02:14:48 PM
For non-civil/survey drawings, I recommend that you do not put your drawings 17,000 miles away, but locate the original intentionally close. To deal with background drawings from others, use XREFs and change the INSBASE, or just move them after attaching.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 07, 2012, 02:19:13 PM
So, being 17,000 miles away from the origin has little or no affect on my drawings accuracy, except for maybe hatches, which can easily be remedied?  Is that correct?

Also, what benefit is it to me to be 17,000 miles away just because the civil drawings are?
Correct on first part...


The second part depends on whether you want to fiddle around with the Civil site plan NOT lining up with your version of the site plan with no added benefit to you for doing so.  And the potential issues of things not being aligned in space should you decide to use your own arbitrary coordinate system (0,0) instead of the real world.

The potential for error and the issues that arise from that; being your responsibility.
One method has no such potential for erros, the other does.

Unless you like doing work that need not be done for free; and with the added benefit of introducing errors that could be terribly expensive. I really can't say.

Here is a handy decision matrix for you:

If all you are doing is shop drawings for millwork, then none of this has any impact on you or your methods. Use (0,0)

If you are coordinating a site plan with the Civil Engineer or Surveyor, then it does. Use the real world.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 07, 2012, 08:10:17 PM
Also, what benefit is it to me to be 17,000 miles away just because the civil drawings are?

I have to agree that it's somewhat puzzling as to WHY the State Plane coordinates are so big.  I don't think I've ever heard an explanation.

I know that when the original State Plane coordinates were created, a bunch of people got together somewhere and came up with the systems, based on their own set of concerns.  But I've never heard any details about the thought-process that went on.

In the original State Plane system, many of the coordinates were smaller.  For example, here in Colorado, the NAD27 State Plane systems use a false easting of 2,000,000, but the false northing is 0.  So while the Eastings are very large, the Northings end up being more like 300,000.  Why they chose an Origin in New Mexico (or was it Arizona?) for Colorado State Plane systems is something I don't know.  Maybe it was just to create "overlap" between zones...  No idea.

But a key reason for the different false northing/easting values is to prevent any confusion between Northing and Easting.  When using Colorado NAD27 State Plane, I always know that the numbers in the 2,000,000 range are eastings, and the numbers less than 1,000,000 are northings.  Similarly, if I'm using Colorado NAD83 State Plane, then I know that the numbers in the 3,000,000 are eastings, while the numbers around 1,500,000 are northings.  And by simply looking at the coordinates, I can immediately identify which coordinate system they are in (well, at least as long as someone doesn't use one of those nasty bastardized "Modified State Plane" sort of systems that look indistinguishable from State Plane coordinates), as well as which one is the Northing and which one is the Easting.

So I understand that much...  But I really can't say why they decided to use false northings/eastings in the millions.  Or how they chose the origins of each zone.  Maybe they also wanted to choose values that were distinct from UTM, or something...  No real idea.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Krushert on February 08, 2012, 07:24:04 AM
I still do not see why I or any other architect has to stop using 0,0 as a coordinate system all together just becuase we have to make your lives easier.  I have said it before and I will keep saying it.  It is a sense of scale.  A apartment unit in 15,000 sq ft dorm building is handled the same as a builing on a 15,000 acre.  YOu treat as a block that you loacate and rotate accordingly.  The building is just one big block (or xref).  It is not like I am setting my base point for a block of a toilet at the 0,0 coordinated of the building (tied to the State Plane or not).

 The only time I need to manuplate a site plan is to extract some basic information like where grades lines are hitting my building.  The actual rotating of a builing in a file should be done by the civil folks, that is their job.

Just my simple probably ingnorant opinion.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 12:53:51 PM
Don't really understand your post.  I also don't understand why you would do an architectural plan in State Plane.  There's nothing in that to make OUR lives any easier.

ESPECIALLY since, when it comes to Civil work, we NEVER trust Architectural drawings.  We use the Structural plans, from the Structural Engineer.  We view the Architectural plans as "the pretty drawings" that indicate how the final construction should look...  They don't really come into play at all when it comes to the Site layout.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 08, 2012, 01:07:27 PM
I would suggest that the 'site plan' be done on real world coordinates for ease of coordination between the two disciplines.
The Architects Building would be an attached reference file, done at whatever coordinate scheme they desire.
Located correctly with respect to the site plan, based off of the Surveyed property lines, which in most cases would reference State Plane.

In this fashion the Civil need not try to figure out where and or at what angle the building sits on the actual site.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 08, 2012, 01:20:15 PM
ESPECIALLY since, when it comes to Civil work, we NEVER trust Architectural drawings.  We use the Structural plans, from the Structural Engineer.  We view the Architectural plans as "the pretty drawings" that indicate how the final construction should look...  They don't really come into play at all when it comes to the Site layout.

Funny, as an architect I never assume structural drawings to be dimensionally accurate. Structural engineers almost never spend the time to keep their drawings updated with all the minor tweaks that occur as part of architectural development.  I never xref their plans, only take structural member sizes off their drawings and draw in my plans, then check all dimensions as part of my coordination. For site layout coordination I always include the property line in my site plan and floor plans to make sure everything aligns. We are often on board before civil, sometimes even before survey, and so I locate my plans with 0,0 as the lower left corner of the property line. Often I will rotate the building plan to orthogonal to XY axis as there is no benefit in drafting all our dozens of plans in rotated UCS. My site plan is in true orientation, with the floor plan xreffed and rotated, using the property lines to match up.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 02:58:20 PM
Funny, as an architect I never assume structural drawings to be dimensionally accurate. Structural engineers almost never spend the time to keep their drawings updated with all the minor tweaks that occur as part of architectural development.

Wow...  I guess that points out the value of forums like this, where each of our collaborative disciplines can start to get an idea of how the others think...

The typical flow is that the Architect has the vision, and creates the building that is desired.  Then that data MUST be transferred to the Structural Engineer, who is responsible for making sure the whole thing doesn't collapse.  And the Structural Engineer takes into account MANY things in that assessment.  When a Structural Engineer comes up with caisson locations, etc., we as Surveyors then trust that judgement.  Locating the building correctly on the site then becomes our responsibility, but we use the Structural Engineer's calculations to layout the foundation of the building.  We DO NOT trust the Architectural drawings...  Maybe because those tend to change the most during development, and they often end up being the files that have the sloppiest linework (in our experience).  But also because details of facade, wall thicknesses, etc., no longer matter.  The architect can continue to change details like that right up until the thing is built, as long as the changes don't affect the structural integrity of the foundation.  The important thing is the foundation layout, as defined by the Structural Engineer, which we stake in the right location based on the Site Plans.  With Architectural plans, we can get into all sorts of arguments about "What exactly does 'corner of the building' mean?  Is it the internal wall structure, the facade, the foundation, something else...?"

If you work with Structural Engineers who produce drawings that are not dimensionally accurate, then I'd be worried....
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Birdy on February 08, 2012, 03:00:31 PM
ESPECIALLY since, when it comes to Civil work, we NEVER trust Architectural drawings.  We use the Structural plans, from the Structural Engineer.  We view the Architectural plans as "the pretty drawings" that indicate how the final construction should look...  They don't really come into play at all when it comes to the Site layout.

Funny, as an architect I never assume structural drawings to be dimensionally accurate.
Structural engineers almost never spend the time to keep their drawings updated with all the minor tweaks that occur as part of architectural development.  I never xref their plans, only take structural member sizes off their drawings and draw in my plans, then check all dimensions as part of my coordination. For site layout coordination I always include the property line in my site plan and floor plans to make sure everything aligns. We are often on board before civil, sometimes even before survey, and so I locate my plans with 0,0 as the lower left corner of the property line. Often I will rotate the building plan to orthogonal to XY axis as there is no benefit in drafting all our dozens of plans in rotated UCS. My site plan is in true orientation, with the floor plan xreffed and rotated, using the property lines to match up.

heh. I never assume anyone's drawings to be dimensionally accurate.  :-)
I burned that bridge bridge behind me long ago.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 03:06:33 PM
heh. I never assume anyone's drawings to be dimensionally accurate.  :-)
I burned that bridge bridge behind me long ago.

Yes, you can always run into incompetence.  Never take anything for granted.  Luckily, though, most of the people we work with on a regular basis are pretty good.  So we can usually trust their work, although as Surveyors, we're often the final QA check, so we have many things we do to make sure everything gets built correctly.  But we DO have to be a lot more careful when working with "unknowns", aka people/companies we haven't really done stuff with before.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 03:11:54 PM
I would suggest that the 'site plan' be done on real world coordinates for ease of coordination between the two disciplines.
The Architects Building would be an attached reference file, done at whatever coordinate scheme they desire.
Located correctly with respect to the site plan, based off of the Surveyed property lines, which in most cases would reference State Plane.

We pretty much do this, although you can run into problems with pre-fab buildings on State Plane.  The usual problem we see is that the Engineer "forgets" (or more-likely, doesn't understand) that distances on the State Plane grid are not necessarily the ground distances.  That can really wreak havoc in some situations.

But as Surveyors, we typically reference the Structural Plans into the Site Layout.  This also accounts for the fact that the Structural Plans are usually done with UNITS=Inch, and we (as Surveyors) hate that.  But by referencing the Structural Plans into the Site Layout, we can set points in the Site Layout, and everything works fine.  I still kind of wish Structural Engineers and Architects would stop using inches, but we can deal with it.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: mjfarrell on February 08, 2012, 04:01:45 PM
It isn't the Structural or Architects 'fault' that inches are a problem.
It is how autodesk has chosen to program for use with those units.
Instead of simply giving them dimension styles that read feet and inches, instead of scaling the workplane.
Not being a programmer I may be oversimplifying this, however there is no valid reason in my mind why is shouldn't have been created that way from day one.
And then we would ALL be working with the same units insdie cad, and we would all be happier for it.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 06:28:25 PM
We actually don't really have any problem with the Inches drawings...  As I said, we simply XREF them into the correct location in the Civil plans, and everything works.

We just don't like inches on general principle.   :wink:

The only thing that upsets me is those rare instances when we get Site layouts done in feet and inches, with control point coordinates given in feet and inches...  Now THAT'S annoying.  Luckily, I can only think of two times when I saw this.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 08, 2012, 09:43:10 PM
It is how autodesk has chosen to program for use with those units.

I've heard that AutoCAD was intended for all ranges of disciplines, and given the limitations of numerical accuracy, the generic unit was intended to be flexible. For Astronomers a unit could equal a Parcel, for molecular engineers a unit could equal a nanometer.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 08, 2012, 09:48:52 PM
Locating the building correctly on the site then becomes our responsibility, but we use the Structural Engineer's calculations to layout the foundation of the building.  We DO NOT trust the Architectural drawings...

There are lots of different ways of working, all the work I have done is design focused and as the architect I direct the location of everything in the building that I can see and locate all columns, all walls, all foundations, etc. When I work with a structural engineer who will dimension every structural element, then my job is to review and coordinate all those dimensions. I do that manually by checking prints, highlighting correct/redlining etc. I also check all the steel shop drawings for dimensions as well. Some engineers won't be bothered with updating dimensions and put all that on us.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 08, 2012, 10:18:36 PM
There are lots of different ways of working, all the work I have done is design focused and as the architect I direct the location of everything in the building that I can see and locate all columns, all walls, all foundations, etc. When I work with a structural engineer who will dimension every structural element, then my job is to review and coordinate all those dimensions. I do that manually by checking prints, highlighting correct/redlining etc. I also check all the steel shop drawings for dimensions as well. Some engineers won't be bothered with updating dimensions and put all that on us.

That sends shivers down my spine...  You think you can trump decisions made by the Structural Engineer...?

Well, I guess as long as you haven't been sued yet....
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 08, 2012, 10:48:06 PM
Who said trump? If I ask for something that doesn't work structurally, our engineers tell us and we work it out. My point is that when I design a building, I make sure I know where everything goes.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 09, 2012, 02:31:31 AM
How does the state plane grid apply to this drawing?
(units = km)
http://autodesk.blogs.com/between_the_lines/2011/02/the-solar-system-drawn-to-scale-in-autocad-dwg-scale-is-everything.html (http://autodesk.blogs.com/between_the_lines/2011/02/the-solar-system-drawn-to-scale-in-autocad-dwg-scale-is-everything.html)
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 09, 2012, 03:01:43 AM
Well, my general response to THAT is "Are you INSANE...?"

Sorry if that seems harsh...   But REALLY....?  Do you seriously think Solar-System-Scale DWGs have any relevance to Civil plans?
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 09, 2012, 03:51:03 AM
I'm actually very distressed about DanAllen's comments.  I think they reflect poorly on both our professions.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: Krushert on February 09, 2012, 07:40:55 PM
There are lots of different ways of working, all the work I have done is design focused and as the architect I direct the location of everything in the building that I can see and locate all columns, all walls, all foundations, etc. When I work with a structural engineer who will dimension every structural element, then my job is to review and coordinate all those dimensions. I do that manually by checking prints, highlighting correct/redlining etc. I also check all the steel shop drawings for dimensions as well. Some engineers won't be bothered with updating dimensions and put all that on us.

That sends shivers down my spine...  You think you can trump decisions made by the Structural Engineer...?

Well, I guess as long as you haven't been sued yet....
Are you  saying a structural engineer drives the team aka trumps the architect?

Architects define the shape and location of stuff.  Structural engineers make it stand up.  At my last job, the sturctural engineer works for us so there is a clear chanin of command.  But a good sturctural engineer will push back when things do not work.  Only a knot head of an Architect would not listen to his team.    And I like Danallen would check shop drawing for size and loaction conformace to the design.  A good team would does that.

Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 09, 2012, 09:19:52 PM
I'm actually very distressed about DanAllen's comments.  I think they reflect poorly on both our professions.

I'm not understanding what distresses you. But to be clear, while as the architect I do set the design and location of the building and elements within, I do that as part of a team of engineers, designers, the owner, etc. We generally intend to work with, collaborate, take input, ask for recommendations, learn from, etc, all the disciplines on the team, structural, civil, landscape, MEP, lighting, acoustics, you name it. But ultimately I am responsible for coordinating all the work with the architecture, and that usually means reviewing and redlining drawings as part of coordination. I understand there are hacks in every field, but on my projects, for the civil to discount my drawings because "structural dictates" is just wrong.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: danallen on February 09, 2012, 09:22:24 PM
Do you seriously think Solar-System-Scale DWGs have any relevance to Civil plans?

No, I just posted to talk about how AutoCAD's units can be inches for architectural, and feet for civil, and there is a reason for that in the context of what AutoCAD is capable of. I've never had a problem scaling up civil and survey drawings by 12 when we xref.
Title: Re: Why are Civil plans 17,000 miles from the orgin?
Post by: sinc on February 09, 2012, 11:24:18 PM
I think we may be all saying the same thing, from different viewpoints.

The Architect is the "artist", who drives it all.  But that can be radically affected by the property boundaries and topology, which fall into the domain of the Surveyor.  That data can then reflect back into the Architect's design.  The Structural Engineer must then make sure the Architect's design doesn't fall down.  The Civil Engineer must make sure details like water, sewer, etc. are taken care of.  The Surveyor again becomes responsible when it comes to site layout.  The Builder is then responsible for making sure the end result reflects the Architect's vision.

None of us can do our job without the rest...