how to constrain

[Anonymous]

im a first time user. I've drawn the main shape and extruded to make rectangular prism. im wanting to 2-D draw lines and dimension and constrain. when drawing lines how do I constrain so that they snap to the edge of the face of the rectangular prism im working on? I draw three lines that make a U but when constraining one line, the other 2 don't move… and when I dimension another it goes out of the main shape. how should I set up everything so that the lines are as one piece and they don't actually move independently.... ie when I move the horizontal one to be centred to the main shape they all move together

[Anonymous]

You can use 'project geometry' when you have selected a 2D face or plane on which to sketch,  this will take care of the lines moving around relative to each other as they are constrained to the line/face picked. The projected geometry will probably be construction lines by default so you will have to change them to non construction lines, then you can extrude them or perform another operation.

Have a look through the tutorials as this will be covered in there.

Hope this helps