6 Replies Latest reply on Apr 30, 2013 8:29 AM by John Burrill

    Why my whole sketch is'nt black?

    John Chimbani

      hi guys

       

      Im in desparate need of help here. I just started learning solidworks and unfortunately i'm stuck...I have homework ive been working on for the better part of 2 weeks without getting it to work. Im doing the course online so unfortunately it takes time before i get a response from my teacher. The thing is has repeatedly mentioned the fact that its important that our sketchlines are all black, without really explaining why! Now im having an issue getting my whole sketch to be black. The thing is its worked when its simpler drawings like sqaures and such. This time though my homework is basically two reactangles stuck together with 3 point circles at each end. The actual sketching is not an issue, but when i start to add my dimensions it seems i can never get the circles to be black. What am i doing wrong???

        • Re: Why my whole sketch is'nt black?
          Ray Howard

          John, it sounds like your sketch is under-defined. You just need to add some dimensions or relations to fully define your sketch. Also, search the help for "Fully Define Sketch", this should get you all you need to finish your task....

          • Re: Why my whole sketch is'nt black?
            Per Engberg

            Screenshot 000073.pngTry dragging the geometry. Any geometry that is possible to move/drag/change is under constrained. Another possibility is to use the automatic dimensioning feature (tools, dimensions, fully define sketch).

             

             

            • Re: Why my whole sketch is'nt black?
              Alan Stoldt

              Some basic constraint to consider.

               

              Hoprizontal and Vertical lines may appear adn also may be so, but not have the Horizontal Constraint, or Vetical Constraint, and so are underdefined. These are easy ones to miss until the have bitten you in the rear enough times.

              • Re: Why my whole sketch is'nt black?
                John Lhuillier

                It sounds like you're missing some relations & would imagine it's the tangency ones for the 3 point circles. Somthing that helps to see whats related is to turn on the sketch relations icons by going to VIEW > SKETCH RELATIONS & pick that so that it is turned on. It will display little icons with the relations that are added to all of the sketch entities. This will help you to see what is & what may not be related. I keep mine turned off because it will clutter up a sketch pretty easy but helps when you;re trying to troubleshoot sketching issues.

                • Re: Why my whole sketch is'nt black?
                  Raghvendra Bhargava

                  hI JOHN,

                   

                  dimension vice if u want to do get your skecth fully black use "Fully defined sketch " option...

                  Right click on sketch entity and option is there..FULLY.JPG

                  In snap you can se...

                  • Re: Why my whole sketch is'nt black?
                    John Burrill

                    John, have you tied your sketch to the origin of the part?

                    Basically, the reason they tell you that you want your sketch geometry to be black (and that should include endpoints and centers) is because Black indicates the geometry's degrees of freedom are all fully constrained so that dragging sketch segments and points doesn't produce any change in the geometry.  You should do the solidWorks tutorial on sketching to get a clearer idea of this.

                    OK, so back to my original point about the sketch origin.

                    You need to have your sketch somehow related to the geometry of the model that you're working on, be it to the origin, reference planes or other geometry.  Chosing the geometry you externally constrain is dependent on the design intent of your model. 

                    If you still can't get the sketch pinned down, post a screen capture of your sketch (while you're in edit mode) or post the part itself and we'll be happy to give you some advice.