how to start a sketch at coordinate z at a height?

[vib]

like in the attachment,i can creat a box from XY plane(which implies Z=0),and i can pull(extrude) to a height ,to say 100,a solid created.then from this plane i want to creat a header at a different XY region.How i can freely draw a sketch (locked) in this plane like i draw in Z=0,XY plane?I have tried UCS(creat a new ucs at the top of the former solid) in 3d,but when i projected to top view to draw the box ,it is still drawn in Z=0 plane,and pull up or down from that plane ,but what i want to creat is an object from height maybe 60 to 100,or even 60 to 70,it do not touch Z=0 at all.This problem confused me for severals days!

[vib]

by the way how to use leader and text to note the solid in 3d,shame to make the note in drawing in other soft.

[MSasu]

Not sure that understand, you were looking to draw in a plan, other than current 0? You should move temporary the UCS (translate on Z) to the desired elevation, draw what you need and revert to previous UCS or WCS when the sketch is done. Only after this final step you should validate the elevation of said sketch.
Please don’t forget that while the UCS is moved, the listed coordinates are expressed in current UCS; thus when you translate it on Z, the draw plan will be always 0.

[ReMark]

Look into the OSNAPZ system variable or maybe ELEVATION?

[Dadgad]

Use dynamic input, and use POLYLINE command or POLYGON or CIRCLE or RECTANGLE.
When specifying your first point use direct data entry like 0,0,200 , and in that way as all of these commands
draw on a plane which is parallel to the X, Y plane in your UCS, you will wind up drawing at the elevation entered in your
first point input.

Command: 11
PLINE
Specify start point: 200,200,500
Current line-width is 0.0000
Specify next point or [Arc/Halfwidth/Length/Undo/Width]: <Ortho on>
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: <Osnap on>
'_+dsettings >>Tab Index <0>:2
Resuming PLINE command.
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: '_+dsettings
>>Tab Index <0>:2
Resuming PLINE command.
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]:
Specify next point or [Arc/Close/Halfwidth/Length/Undo/Width]: c

For better viewing and enhanced control, do your PRESSPULL or other modeling commands from an isometric perspective, in this way you can enter direction and it
won"t default to zero elevation on the Z axis.

[ReMark]

If one were drawing multiple objects at an elevation other than that of 0.00 what would be the quicker way of doing it?

[Dadgad]

If one were drawing multiple objects at an elevation other than that of 0.00 what would be the quicker way of doing it?

I would just draw it or them on the current layer, then LEVITATE it maybe my Levity is misguided,
perhaps ELEVATE would be better.

[sp]

you could go to tools/new ucs/ then object and pick top plane.

[Denimoth]

You can set your UCS origin to whatever height you want using the 3 coordinate values, or by clicking on an endpoint of an existing 3D model.
Command: UCS
Specify origin of UCS or [Face/NAmed/OBject/Previous/View/World/X/Y/Z/ZAxis] <World>: Origin
Specify new origin point <0,0,0>:0,0,60

Now whenever you draw an object, it will be at the height you set your UCS to.

[rkent]

by the way how to use leader and text to note the solid in 3d,shame to make the note in drawing in other soft.

You need to manipulate the ucs to do this. In your example the ucsicon has x,y plane shown as if on a top view with Z pointing up. Use the UCS command and rotate the UCW so the Z is pointing toward you from the left plane. Try using UCS, Object, select the object for A. It takes some practice, the newest releases make manipulating the UCSicon much easier, not that that helps you any.