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How do I enter coordinates to "close" the property lines properly?

Thanks.

There are two things you need to do to imput the information from a boundary survey.
1) Switch your Angle Type to Bearings
2) Switch your Scale Type to Decimal

You be able to find the format to use for these items with the online Datacad Manual. I hope this helps.

boofredlay wrote:How do I enter coordinates to "close" the property lines properly?

As far as "closing" the property lines go ... I have found over the years that the plat information of the sites that I have had to input rarely ever actually closes, with the exception of simple rectangular sites. The math just doesn't close. Usually, the discrepancy is less than an inch.

Steve,
I have found the same thing. I usually just end up stretching one of the lines to make the boundary "close". Surveyors use a ratio to determine if they are within closing limits, so the large the site, the more the lines will be off.

Hello Guys,

The surveyors use an 'error compensation' to distribute each particular difference proportionally for every segment. So, they can close polygonals with the best accuracy as possible.

The increase of accuracy of DataCAD, by using double precision in V11 will make DataCAD much more useful in this area.

And more, today's mass increase of GPS will require better dealing with big numbers for describing real world coordinates.
Dave and Crew are aware of the limitations that still are present, and we hope they will be able to address it for V12.

Regards,
Miguel

Miguel Palaoro wrote:The surveyors use an 'error compensation' to distribute each particular difference proportionally for every segment. So, they can close polygonals with the best accuracy as possible.

So ... what you're saying is that none of the surveyor's lines are actually what the numbers say they are ... XXX.XX' - Nxx(d)xx'xx"W, etc. etc. etc.? Does this also mean that when I input the legal information per the plat (using the numbers), I should also have to somehow cheat all of the lines?

Miguel Palaoro wrote:...The increase of accuracy of DataCAD, by using double precision in V11 will make DataCAD much more useful in this area.

We use to have the same gaps everyone was use to on pre-11 version of Datacad. But since 11, I don't think I have had to fudge any sites yet. Double presision has been great. Probably done about 200 7000-60000 sq.ft. lots. I'm sure like Miguel says there are still some limits when dealing with the "Mars" type measurements, but for us it's been great.

Hello Steve and Josh,

I don't know how much am capable to understand and explain it, but will share my mind with you trying to explain some understanding. Later perhaps we can come back to extend some more of this subject that is very absorving.

Indeed Topography and Cartography are not the same thing. Both disciplines deal with coordinates, but none of them can be considered the absolute 'true' for the coordinates information. Roughly it would be:

When you survey using a landed device, you will get a relative coordinate to some reference mark, which already includes some kind of correction. This is topography.

When you make the survey using a GPS you will get an absolute coordinate, related to the Earth as an ideal sphere. This is cartography. To make usable this data you must correct it using a so called 'Geoid' which considers a defined altitude over sea, by nothing more then a conventionned data, accepted by each country individually.

DataCAD now can make the drawing representation of any survey, by any origin, and Release 11 has achieved a great proximity to the most accurate as possible, and my hope is that the remaining problems with data presentations, when the place is very far from the origin, will be addressed soon.

BTW, I'm sure we are all in the right track.

Thanks,
Miguel

Ok, I cannot seem to find anywhere in any of 5 manuals I have access to that tell how to draw property lines using bearings.

Would someone please guide me through the process.

I found an old post on the subject.
Thanks anyway.

Here was the post:
-------------------------------------------------

Change your Angletyp to "Bearings" in the Settings menu and set the Startang to point towards North(usually straight up the page).
Change the coordinate setting (Insert key) to Relative Polar(Distance/Angle)
Change the Scaletyp according to unit of measurement(Decimal, Engr, etc.).
Now, to enter coordinates simply start a line with your mouse/cursor, hit the spacebar and you're prompted to enter the "Distance" and "Angle".
The distance is (hopefully) self explanitory. To enter the angle use periods(.) in lieu of degrees, minutes & seconds. (ie N45.15.32W)
No spaces or tick marks and upper or lower case don't matter.
Hit the space bar to begin the next line at end of previous line, and so on.
To check your survey accuracy, the last coordinate entered should close the boundary and the cursor should end up at the exact "point-of-beginning". If it doesn't then either you have made an input error or the survey is incorrect.

Typically when I want to draw property boundaries I do the following:

1. Start New Drawing....
2. Go to Settings...Scaletype...F3 Decimal
3. Go to Settings...Angletype...F2 Bearings
4. Set my input mode to Rel. Pol.

Now simply click where you want your start point....enter the distance....type out the bearing using "." (periods as the separators)
IE n5.22.34e for North 5 degress 22 minutes 34 seconds East

This should help get you going.

I found that entering property lines using bearings and distances to be one of the easiest tasks to do, especially with a Cad program like datacad.
Maybe it is because of my two summers spent surveying. Unfortunately it is a difficult concept for others, maybe because they are so ingrained in drafting floor plans using orthagonal coordinates.

The hardest part is reconciling difference between the compass direction (true north) and the orientation of the plan as laid out on the sheet. Much of our work relates to existing buildings so we begin with the floor plan and the site plan comes later.
Engineers usually orient the site plan the best way it fits on the sheet, along with a north arrow, so now you have a third orientation to deal with when you get the cad file from the civil engineers!
Add in a "project north" so you can do the finish material schedule, as true north is commonly about 45 degrees from the way you have orientated the floor plan.

And yes, most of the surveys do not close, most by an undiscernable amount when plotted out a scales typically used for site plans and would never be noticed when drawn by hand.

Xrefs are especially useful when putting the building on the site or putting the adjacent site information on the floor plan.