is it possible to set the angle between two pairs of lines equal to each other?

ron_zimmerman

I want the angles between two pairs of lines to be equal, but I want it to be variable.  Obviously, I can dimension both angles to be 20 deg or any other size by typing in a value.  
When I make the length of two lines equal, I can drag one endpoint and all the equal length lines will automatically update with no length dimension.  
I want to do this with angles.  
The equal constraint will not pick dimensions. 

brian_brady

I would really, really like this feature for angles. Even a way to make dimensions equal would do the trick.

NeilCooke

Can you make some of the lines parallel? Also another trick that might help is to create a construction line on each set that makes up a closed rectangle then make the construction lines equal - this will only work of course if the angled lines are of equal length. One final way is to create a variable outside of the sketch and drive both dims with that. 

brian_brady

NeilCooke said:

... One final way is to create a variable outside of the sketch and drive both dims with that. 

In my way of thinking, a parametric model should have the minimum number of dimensions necessary to define a sketch. If features are supposed to be and stay equal to each other, there should only be one dimension and a number of equal constraints.

I run across this problem often for sketched fillets. OS automatically adds a dimension to every fillet (unlike lines and arcs and circles that can be dimensioned later). If I have 2 or more fillets that I want the same, I have to accept the dimension, leave the fillet tool, delete the dimension that was just added, and create an equal constraint for the duplicate fillets. Very unlike the rest of the OS sketching tools.  As (another) aside, I would like to see equal running inferences while sketching. This would save a lot of time where you have to make the same size circle or line or anything else in a sketch. Currently you have to sketch them all then use the equal constraint tool and start picking pairs. Which leads me to another aside, why can't more than 2 items be selected for an equal constraint?

NeilCooke

brian_brady said:

NeilCooke said:

... One final way is to create a variable outside of the sketch and drive both dims with that. 

 Which leads me to another aside, why can't more than 2 items be selected for an equal constraint?

You can if you preselect all the edges first then press the equal constraint.

ron_zimmerman

Neil,
None of the lines are necessarily parallel.  
I was able to use congruent triangles to control the angles by controlling the length of the lines.  It's just a lot of extra steps.  
Is there a tutorial on creating and using variables?

emmett_weeks

@brian_brady, if you select sketch curves before clicking the equal constrain tool (or pressing e), it will apply the equal constraint to everything at the same time. It'll still make multiple equal constraints, but it distributes them efficiently and saves mouse clicks. This works with other constraints as well. If a circle and two lines are selected and then the tangent icon (t) is clicked, it will make the circle tangent to both lines.

The fillet workflow does need a rework. If multiple fillets are made at the same radius in a row, it will create equal constraints between fillets rather than make a new dimension for each, but the way the fillet tool works makes this workflow a bit buggy. @lougallo, can you add Brian Brady to the improvement request for this?

brian_brady

emmett_weeks said:

@brian_brady, if you select sketch curves before clicking the equal constrain tool (or pressing e), it will apply the equal constraint to everything at the same time. It'll still make multiple equal constraints, but it distributes them efficiently and saves mouse clicks. This works with other constraints as well. If a circle and two lines are selected and then the tangent icon (t) is clicked, it will make the circle tangent to both lines.

The fillet workflow does need a rework. If multiple fillets are made at the same radius in a row, it will create equal constraints between fillets rather than make a new dimension for each, but the way the fillet tool works makes this workflow a bit buggy. @lougallo, can you add Brian Brady to the improvement request for this?

Thanks. I have been first selecting the tool, then the geometry (habit). Regarding the fillets, I just tested this and it works only if you don't enter a radius value right after selecting the first corner to round/fillet. If a value is entered, then the next one wants a value as well. I think the better workflow would be to not require a number (just like lines and circles) but allow for a value entry. If no value is entered, every fillet is independent in size, no equal constraints. If a value is entered, then all following fillets are equal until a new value is entered.

I will adjust my workflow with this new knowledge. This is why I encourage my students to visit the forum if they can't figure out how to do something. Lots of people are willing to lend a helping hand.

edit: I noticed that the same size workflow only works if you select the vertex not if you select two lines instead. It would be nice if this were consistent. 

ron_zimmerman

@NeilCooke
I went through the variable creation and use tutorial.  The feature script 'measure distance' is what I need.  However, it appears that sketch features don't work.  When I create the measure distance variable and select two lines or two points in a sketch, I get an error message "did not regenerate properly.  cannot resolve entities".