1. ## Contour from points

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Hi Guys,
My name is Kyle and I have been in the Cad buisness for a few years now I am currently in school and have a really stupid question. I received a drawing that I needed to do topo on. My teacher is telling the students to draw each contour. there are random countour shots on this drawing is there a way that I can build a surface from points inserted to a drawing? I know im going to get flamed about this but I cannot do it the way the teacher is asking. The points are not given a x,y,z cordinate they are drawn in 2d so i was hoping there was a way I could make them useable to build a surface. Please tell me there is hope.

Thanks again Kyle.

2. Do these points have elevation text beside them.....if they do then I have a lisp routine that will allow you pick the point, then pick the text, and it will create a 3D point there with the Z value of the text......

3. Why can't you do it the way the teacher is asking? Just interpolate where the contour would cross between 2 points; do it enough times and you should be able to draw the contour lines by "connecting the dots". Maybe the teacher wants you to gain an understanding on the method of contouring.

4. Are you at school for cad or for surveying, as lpseifert said interpolation is a valuable skill to learn.
so you have some random spot levels, draw a line between 2 points and if the line is say 10 units in length and the height difference is 5 then each 1 unit (xy distance) is a change in 0.5 height difference this will help you locate the contour/s between the spot levels.....

btw - there are no stupid questions just stupid people for not asking

5. Another easier way to interpolate is to use a scale ruler and set square.....the way we used to do it pre computers.......

Bit too hard to explain it here though........

6. What.. before computers.. there was never such a time...next thing alan will be going on about french curves.. not the good ones though

7. Hmmmmm.... Raaaiiilllllwwwaaaayyyy cuuurrrvvessss

oops, sorry - this isn't chat is it?

it should be remembered that when a teacher gives out an assignment it's not to produce whatever the assignment tells you to produce, it's to utilise the scenario to impart a knowledge to you - so if you aren't willing to have a stab at it, jack the course in

this forum is great for finding out the half a dozen other ways to achieve the same thing, and gives you a much deeper and broader knowledge than your college syllabus is designed to cover - don't cheat on those assignments though, we can't be there for your exam

8. Originally Posted by Alan Cullen
Another easier way to interpolate is to use a scale ruler and set square.....the way we used to do it pre computers.......

Bit too hard to explain it here though........
Wow, that's old school Alan.

9. Killergtz
First of all: welcome in the forum!
I renamed this thread; all the questions and answers posted in the forum are sources for other AutoCAD users, so please use relevant titles to make the forum easie to search.
As the answer to your question: try to draw a spline trough the points of the same contour.

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WOW thanks for all the replies guys didn't think this question was gonna be such a hit. Now I think I need to fill you guys in on a few things before I continue. My teacher for this class quit two weeks ago and we have a archtectural teacher trying to cover our civil class. I am much more experienced in the civil field than my teacher is but have not worked in the field in quite a while. My current teacher only has a few weeks (2) to be exact to give us a final project and final exam. This particular project that she gave us was to take these spot shots and as lpseifert said interpolate contours between them on a sheet of paper (DONE). Now after this she wanted us to go into cad and insert the contours (just splines or polylines not really contours) once you have placed them all correctly like you did on your sketch she wants you to extrud these lines up to there elevations. (LOL) Now I hope this makes it a little more clear on y I do not want to do it the teachers way. Once you extruded these lines they want you to fillet them all to make an elevation. Ok so after read some of the post here is what I have

X 395 This is all I have a bunch of these random elevation numbers there are no coordinates or x,y,z descriptions please guys I remember adding points into a existing surface to help aid in correcting a topo that looks awful but have never done it without survey points and information. I want to build a surface out of these points can it be done?

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