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Dear PTC.....

headrush

New member
Fix your @$%*&! sketcher constraints! The supposed conflicts shown are not actual conflicts. If fact, in the situation I am looking at right now, there are no conflicts. Yet I can't create the geometry I need. All I want is an arc which is tangent to two lines. The radius of the arc is undefined (it can be whatever radius is required). The arc can attach to the lines anywhere. After trying 10 different ways to do a very simple thing I finally succeeded. When a 3 second task turns into a 10 minute task productivity is reduced by a factor of 200.

You've been at this for 35 years and your software is still an EPIC FAILURE! In fact sketcher constrains used to work fine, which means the software is getting worse.
 
I concur. Often I've had to break up a feature into several separate features to make the sketch easier to make. It seems to me the more elements in the sketch, the more unlikely pro is to assume the correct constraints. It can be very frustrating. I've even tried to purposely sketch way out of scale so no constraints are assumed and then add them later, but pro will assume additional constraints as you are adding them. I agree that this has not always been as big of a problem as it is now. This is someplace that large improvements could be made.
 
This is a fairly common problem with people new to the, "Pro/E way of thinking".

In general, you should try to limit your sketched sections to no more than 12-15 entities (lines, circles, arcs etc.). If you need more than that, then you run the risk of over constraining things and having the sketched section "get out of control".

Keeping your sketches simple and small, you will ultimately have better control over your design and more robust results.
 
Headrush, I too have struggled with the situation you described: arc tangent to two lines. It shouldn't be as difficult as it often is. I am in the habit of using the Racetrack Shape from the Sketcher Palette as much as possible just to avoid fighting to get the tangent constraints to work they way I intend.

Using config settings to disable some of the Intent Manager's constraint creation has also been helpful. For instance, the Intent Manager puts equal length constraints on line segments about 100 times more frequently than I want to, so I have the option sketcher_equal_length_constr set to no.

One other random item about 3 point tangent end arcs which took me a long time to learn: after you click the initial end point on an segment you see a green circle with four quadrants. If your cursor leaves the circle through one of the quadrants which align with the segment then you get a tangent constraint, if it leaves through one of quadrants perpendicular to the segment then you don't get a tangent constraint.
 
Thanks for the helpful replies. You learn something new every day. Often we just deal with a situation rather than find a solution.
 
What really drives me crazy is the opposite condition with a Fillet.

Two additional construction lines are created to represent the theoretical intersection.
The problem is when you are adding a fillet between a sketched line and existing geometry, the construction lines are created without dimensions or constraints.

What used to be a simple one-click feature has turned into several operations consisting of dimensioning and constraining extraneous lines I don't need.

It's simpler to just sketch a radius and trim the corner lines
 
I'm not saying this eases everyone's pain, but this seems to help me out a lot when my sketch exceeds a single digit number of entities. Has anyone held Shift while sketching? It temporarily disables automatic constraining. Yes, I've experienced arc tangency troubles to which I've had to play with it a little to get it right and have, case by case, learned what is most likely going to work the first time around. I've also experienced the 'opposite fillet' problem, yet the majority of the time, Shift makes sketching a great deal easier.
 
Of course, you can also RMB (Right Mouse Button) on any constraint and disable it individually. RMB over each constraint several times to see each available option.
 
What really drives me crazy is the opposite condition with a Fillet.

Two additional construction lines are created to represent the theoretical intersection.
The problem is when you are adding a fillet between a sketched line and existing geometry, the construction lines are created without dimensions or constraints.

What used to be a simple one-click feature has turned into several operations consisting of dimensioning and constraining extraneous lines I don't need.

It's simpler to just sketch a radius and trim the corner lines

Use a Circular Trim and you won't get these construction lines. This entire thread is a result of not fully understanding the tools. Every tool has rules and if you don't follow them, it doesn't work as expected. There are techniques and best practices for feature creation. Large numbers of entities in a sketch is a very basic no-no. Simple sketches and more features is always a better method.

I'm not sure why there is a problem with the tangent arc. Sounds like something is up with the technique being use. I've never had a problem with such a thing.
 
maybe i missed something, but i agree abouyt keeping your sketches "simple" and a recomendation from PTC (old one) is that a sketch shouldnt have more than 30 enteties. If your sketch contains a lot of enteties, i bet your model will be more difficult to update, iow "less robust"

As mentioned before , use shift button, and use you RMB to controll the constrains while sketching.

//Tobias
 
I don't try to draw to many arcs because they are aggravating. I just draw the lines and use the fillet tool to connect them. This works great when you want to draw an arc tangent to two circles.
 
Use a Circular Trim and you won't get these construction lines. This entire thread is a result of not fully understanding the tools.

I understand them just fine.
Like I said before and you have confirmed,
Fillet used to be a one step operation and now it has turned into a multi-step operation consisting of a combination of constraining and dimensioning or trimming and deleting.

That is a step backward
 
I agree. I like the new fillet tool. I fillet the corner, give it a radius just as before. I like having the theoretical corner as it gives more control when needed. When it is not just don't mess with the construction lines.
 
Fix your @$%*&! sketcher constraints! The supposed conflicts shown are not actual conflicts. If fact, in the situation I am looking at right now, there are no conflicts. Yet I can't create the geometry I need. All I want is an arc which is tangent to two lines. The radius of the arc is undefined (it can be whatever radius is required). The arc can attach to the lines anywhere. After trying 10 different ways to do a very simple thing I finally succeeded. When a 3 second task turns into a 10 minute task productivity is reduced by a factor of 200.

You've been at this for 35 years and your software is still an EPIC FAILURE! In fact sketcher constrains used to work fine, which means the software is getting worse.

Just hold down 'shift' when drawing the arc and then constrain the arc once drawn. Think that feature has been there for 35 years as well ;)
 

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