"Trim" tools don't "join" properly

[propstuff]

Greetings,

I regularly need to make polylines and polygons out of circles. lines and arcs to be extruded into solids for further manipulation. ( think of a lever crank arm: place 3 circles on a page, place 3 lines that cut into the circles and make a "triangle" with circles at each vertex, and then join the circles to the lines with the fillet and trim tool.)

Using the Fillet and Trim, and the Trim tool, the lines and arcs are supposed to be trimmed back till the ends of the 2 lines etc are coincident with each other. Using the Compose command on a closed series of lines should then yield a single closed polyline.

The problem is that -more often than not- one or many of the trimmed intersections fail to join properly, and 2 or several polylines are created.

Even going individually to each intersection and picking up the end of the line segment, moving it away and "resetting" it using the Snap Constraints fails. The Snap says it has found the end of the other line or arc, but when Composed, it fails to join.

Often the only way to make it work is to use the parametric constraints and "force" the end points to be coincident. Very time consuming, and annoying when half the time it works properly and half the time not...........

How do I make this work ALL the time??

N.

[Kaare Baekgaard]

You may consider to use the connect/combine tool. It will connect or combine not only two lines, but also two arcs or a line and an arc.

[Kaare Baekgaard]

You may consider to use the connect/combine tool. It will connect or combine not only two lines, but also two arcs or a line and an arc.

By the way: make sure, that the "snap to grid" is disabled when you manually try to connect two objects.

[Guest]

The smart cursor cue you get when you connect the lines so the compose and connect combine tools work can determine if the objects will connect or not.

If a line is connected to an ARC the ARC END cursor cue needs to read when drawing a line to or from an arc.

If it's a circle that's been clipped, POINT should be the cursor cue. HOwever, as Karen suggested, if you have Snap to Grid constraint on, the POINT can be to either the clipped circle OR to a point on the grid. Hence the good idea to turn that constraint off.

[propstuff]

Hi Kaare and Katie,

I don't use the Snap to Grid (as a general rule).

The Combine/connect tool is one I use in this respect along with the trim etc, and it is perhaps rather more reliable than the trim tool, but the same problems occur.

The smart cursor cues I use extensively ("arc end" etc) but I'm starting to think that these are part of the problem.

That is; when cues say they have "found" the end of the line/arc etc and the click is done to place the end of the next line etc, the two points do not coincide. This inaccuracy is dependant on zoom level it appears.

I've yet to pinpoint why and where exactly what is causing the problem :-(

N.

[P Retondo]

propstuff, I tried the circle and line experiment, in a slightly different way. I used the "split by point" tool to make the circle into an arc at the intersection with a line, and found what I think is a bug. When I split a circle at such an intersection, it became an arc of less than 360 degrees. One side of the arc lay on the intersection, the other side some distance away. This appears to be a replicable problem. When I split that arc again at another line intersection, the arc end point did not lie on the intersection. I could actually draw a line between the split point and the actual intersection that had a fairly large magnitude (L = .08" on an arc of 3' radius).

I will submit a file illustrating this problem to bugsubmit. It is likely that the same chunk of code involved in this bug is responsible for the problem you are observing.

On further experimentation, it appears that a 360 degree arc is an illegal object - try to make one and see what happens. I also found in a couple of test files that the "split" tool failed to operate on an arc at the intersection point, and I had to create a fresh file, in which the exact same operation worked.

[ 08-20-2003, 01:54 AM: Message edited by: P Retondo ]