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psu503
14th Jul 2011, 06:27 pm
So the problem I am having is when I try join lines and/or make a polyline. I am trying to model an electron lens and have all the measurement and angles correct but Autocad does not want to allow me to join the lines so that I can make a 3D model for export. When it does allow me to join all the line or make a polyline, the lines are not straight. Granted I have to zoom in to see the deviation in the line but my connecting lines are not orthogonal like they should be. Here is a picture of what I am trying to make. If anyone has any suggestions or tricks that a beginner would not know that would be great.

Thanks all.

The main problem area is the gray part 28700 (Don't know if you can see my attachment)
28699

ReMark
14th Jul 2011, 06:32 pm
Other than the obviously curved lines I see nothing that should/would cause you any problems.

Post the drawing. Someone here will take a look at it and tell you where you might have gone wrong.

psu503
14th Jul 2011, 07:58 pm
file:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot.pngfile:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot-1.pngfile:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot-2.pngfile:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot-3.pngfile:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot-4.pngfile:///C:/Users/nkuperma/AppData/Local/Temp/6/moz-screenshot-5.pngDid I not post the drawing? Not sure how to do that.

Also I am wondering if it is common for polylines to not connect at 90degree angles and also some corners are being cut off. When I click on the line and zoom in, there is a red dotted line that shows where the corner should be but the actual line is trimmed short. With the curved surface, what I did was create a line and then as the points I input 100 data points for the curve I needed to model. I got the points using excel and copied and pasted the points directly into autocad (not sure if this is the standard way to make a curve from a given equation but it seemed to work for me).

rkent
14th Jul 2011, 08:12 pm
So the problem I am having is when I try join lines and/or make a polyline. I am trying to model an electron lens and have all the measurement and angles correct but Autocad does not want to allow me to join the lines so that I can make a 3D model for export. When it does allow me to join all the line or make a polyline, the lines are not straight. Granted I have to zoom in to see the deviation in the line but my connecting lines are not orthogonal like they should be. Here is a picture of what I am trying to make. If anyone has any suggestions or tricks that a beginner would not know that would be great.

Thanks all.

The main problem area is the gray part 28700 (Don't know if you can see my attachment)
28699

You can't join splines, pick on the spline, then right click to bring up a menu, pick spline, then convert to pline. Now use join to connect them all. Better yet use the region or boundary command and pick in the middle of a closed area.

The spline has way too many points in it, this will make the model hard to work with, especially if you make this into a 3D object with revolve, etc. When you convert the spline as above, use a small number when asked, or draw over the top of it with the pline command and use spline option in pedit to show it curved.

psu503
14th Jul 2011, 09:06 pm
Thanks, I Will try the region or boundary commands. One thing that I noticed with the join command is that not everything joins. I converted the curve to a polyline and everything but when I join one some portions of my project join together. different regions join together but not as one unified object. I am just trying to learn all the tricks and subtleties to CAD.

ReMark
14th Jul 2011, 11:31 pm
You can't substitute arcs for the curved sections? Arcs and lines can be joined via the Pedit command.