# Thread: making surfaces from lines

1. ## making surfaces from lines

Having trouble with what looks like a basic function, can't seem to make a surface inside a rectangle of lines.
First I make 4 points, say 0,0,0 0,5,1 5,5,2 5,0,3
Then I use line/join to make 4 lines, rectangular shape.
Now I want to have a surface inside this rectangle, so I'm trying to use: 4 edged surface
Select first chain, and indicate direction, OK. Then it says select next chain in sequence, so I hit F3 to finish.
Then it says select next chain, but all 3 of the other lines become highlighted in red?? I try selecting the line on the opposite side of the rectangle, but the arrow that appears for selecting the 'direction of chain' is pointing in the wrong direction.

what's going wrong?

2. why do you try to use Loft or Rule feature.

3. You need to do the following:

1. Select the first line, then direction, then right mouse button.
2. Select second line (opposite first), then direction, then RMB.
3. Third line as above.
4. Fourth line as above.

Here is a picture of the results.

Chris

4. You can also use (Surface from Curves) and it only takes 1 mouse click.

5. The result of those lines with those coordinates are not all on one plane so actually the "Surface from Curves" will not work. But a "Cross Sectional Surface" will work though.

6. ok thanks for the tips, I'll give them a try
kevin

7. ## Cross Section Explanation

Kevin,

Here is a link to a video demonstrating how to create a cross sectional surface using the line coordinates you posted.

The cursor is highlighted yellow and left clicks are shown as a blue ring around the cursor and right clicks are shown as a red ring.

The rules are as follows:

1. Left click to select entity.

2. The location of the cursor in relation to the midpoint of the line determines direction ( all entities are to be selected in the same direction)

3. Left Click locks directional arrow.

4. Right click ends selection.

Repeat for next section,

After all sections have been chosen, a final right click creates the surface.

More complex chains use the same method, but the additional entities are selected as part of their section.

http://www.onecnc.com/support_videos...ct_surface.exe

OneCNC-USA

8. Thanks for your helpful list of rules, I see now how easy it can be.

Is there a web site that lists the rules, or the support videos? The link you sent is directly to an executable, not something I'd generally run, and the directory listing at the parent website is blank.

I've just signed up with the club at onecnc.com, perhaps in there?

thanks
Kevin

9. kevin,
They have some more videos on a FTP sever at onecnc.com that you can log on to and download.