Plane in Cad

[User2012]

When an appropriate object snap in CAD doesn't appear (see dwg file attached, the only snap that I got was "Center") in order to draw some construction lines on a curved surface, I am wondering whether we have access to "Plane" in CAD (e.g., Front Plane, right... in the same way we do in solidworks)!

[rkent]

I am on 2013, there are 3DOSNAPs, check the icons at the very bottom of the screen for that one. Right click and set the ones you might need.

[User2012]

Actually both 2d and 3d object snaps are on! I assume because my 3D model is more like a curved surface(see dwg file enclosed), other snaps can't be applied. So I wish I could use the Plane in the same way i do in SW. But honestly, I never tried Plane in CAD! So no clue how that works!

[JD Mather]

But honestly, I never tried Plane in CAD! So no clue how that works!

SolidWorks is CAD?

In AutoCAD - UCS.

[User2012]

SolidWorks is CAD?

In AutoCAD - UCS.

If I got it right, I should drag UCS on the surface that I would like to work on. But still I have a hard time to draw on a curved surface even though the object snap is on ( see the link). Becaz of that, I though that there might be the "Plane" or some other ways to do this in Cad as well!

http://www.screencast.com/users/CAD_...7-1140e0770ec1

[kencaz]

AutoCad does not work that way... What is your intent?

[User2012]

I just wanna draw a 2d sketch on a curved surface in cad.

[JD Mather]

A plane is a plane is a plane - in SolidWorks or AutoCAD or any CAD program.
A plane cannot be a curved surface.
A curved surface is not 2d so you cannot possible have a 2d sketch on a curved surface.


You can create a plane (UCS in AutoCAD) anywhere you need it to draw a 2d sketch.
You can project (various ways) 2d sketch to curved surface.

The command is UCS. (you will need to become very familiar with this command so find the Help reference)
Just like SolidWorks you might need some pre-existing reference geometry. Once you understand the process it is the same in any CAD program.

If I got it right, I should drag UCS on the surface

Where are you getting your (erroneous) information?
What book are you using?

Attach your file here.

[User2012]

I understand that the plane cannot be a curved surface and a curved surface is not 2d!
I just thought that I should creatework planes to draw the right sketch on a curved surface and then project it to the surface! But now I realize that I have to use UCS in AutoCad instead. Can I simply drag the UCS icon into the drawing?

PS- I'm gonna learn more about it for sure!Thanx for the Info.

[JD Mather]

Can I simply drag the UCS icon into the drawing?

No.
The UCS is Exactly the same as creating a plane in SolidWorks.
A plane is defined by 3 points.
an origin
x direction
y direction
SolidWorks and AutoCAD have different aids to define these 3 points, but once you understand what is happening in the background you should be able to create a plane (UCS) in any desired location. This is perhaps the most confusing part of 3D for beginners, but nail it and you will be much more comfortable working in 3D.

I recommend that you type UCS Enter
Hit F1 key
review each of the options and bring up question here one-by-one on any option of the UCS command that you do not understand.