Sketch: Construction Lines Moving Unexpectedly

[kevinwatts]

Construction Lines Moving Unexpectedly

1. In the following Sketch, construction axis lines were placed and anchored.
2. Four additional construction lines of the same length were then added aproximatly 1 inch eather side of the center axis.
3. Each of the four construction lines were then selected along with their respective center axis line and their respective location from the center working axis was dimensioned to 3.75 inches.

The contruction lines are moved as defined by the dimension, as expected. However, notice that the lines have also randomly shifted along their perpendicualr axis. I have not seen this before. This should not be happening.

Note: Construction Lines prepared, with main working axis lines locked, before dimensioning.Note: Construcion Lines have shifted after dimensions added.

[Brady_Fulton]

I think you need to lock down (fully constrain) that middle vertical line. Maybe a coincident (Midpoint to the origin) or a Symmetry (endpoints to the middle horizontal line?

[kevinwatts]

Thank you Brady for your sugestions.

Yes, It is a good idea to insure that the X/Y axis construction lines are locked in position. In this example, both were locked down before adding any other elements to the sketch.

As a rule of thumb, I would not think it practical to constrain all of the other construction lines. Unless you know that is the desired effect that you want to have maintained moving forward with the sketch.

I belive that the "jumping" movement as shown was solved in a previous update some time in the past.

Kevin

[TheCADWhisperer]

Can you File>Export and then Attach the *.f3d file here that exhibits this behavior?

[kevinwatts]

I suspect that this is caused by a "test code routine" that is used for debugging.

When dimensions are added to the sketch, several of the perpendicular the construction lines shift 0.75 inch.

Only 6 lines were drawn in the sketch to find this error. Therefore it is not hard to reproduce. It is not unique to a design file.

Lines should not move unless you move them and/or add dimensions.

Kevin