Cannot Trim Circle between tangents

[Bane]

Hi,
Sometimes I have problems with AutoCad Map 3D.
I drew two connected lines. Using the command Draw > Circle > Tan, Tan, Radius, after selecting two tangent lines and give the radius, I drew a circle and everything is o.k.. Now I want to trim a part of circle and want only part between tangent points to stay. I can't do that very often. When I try to find the points of intersection (or tangent points) between lines and circle, they don't exist.

Why this happen?

[CarlB]

If you're in a drawing area with large coordinates (say over 1,000,000 for x or y), all sorts of strange things like this can happen.

[SLW210]

Try posting the drawing or at least a screen shot.

[Bane]

Yes, I am in the drawing area with coordinates over 4000000. But why this happen? If I understood you well, this should not be happened if I use the same object at drawing area near the origin?

I tried this now. When I copy the same objects near the origin, and try to trim the circle at this area, whole circle is erased.

Maybe I must find a place in the space where this can be done?:D
So many strange things happen...

[Bane]

O.k., here is the dwg.

Try posting the drawing or at least a screen shot.

[Alan Cullen]

The mapping grid coordinates you appear to be using will work normally in Map 3D 2008, so disregard that aspect as suggested by Carl. That issue would definitely be a problem in vanilla acad.

I've had this problem often, I just draw a line from the centre perpendicular to each tangent, and use them to trim.

[CarlB]

After copying to near 0,0 there's still the problem that what you drew is still not really tangent. So re-draw tangent lines, then you can trim.

Alan, I hadn't heard that Map 3D had fixed the precision error inherent in AutoCAD. Source?

[SLW210]

For whatever reason, I cannot get that radius to intersect with the circle at 600, but other radii will, some larger and some smaller.

[Bane]

Drawing lines (using osmode 1) over existing lines didn't bring anything new to me. I will draw using Alans' advice till further.

[quote=CarlB;133979]After copying to near 0,0 there's still the problem that what you drew is still not really tangent. So re-draw tangent lines, then you can trim.

[Bane]

Try with different lines and circles. The problem will occur very often.


For whatever reason, I cannot get that radius to intersect with the circle at 600, but other radii will, some larger and some smaller.

[CarlB]

Drawing lines over existing lines didn't bring anything new to me
..yes, because the lines you draw are still not tangent, try drawing lines using "tangent" osnap, closer to the origin.

[Alan Cullen]

Carl, years ago when we ran vanilla acad, that was a big problem, when we changed to Land Desktop, at the advice of our acad reseller (who said Land Desktop had fixed the problem), we never had the same problems again. So I'm just assuming that all vertical civil versions of acad have also fixed the problem. Having said all that, I would not be at all surprised if there were still some minor issues existing with the mapping coords.

[Bane]

I have tried this. It's ok near the origin, but problem still exists if I use large coordinates for X and Y.

I can't move my drawing over the drawing space every time since it is strictly defined in space. We must note that this is very annoying bug in AutoCad Map 3D 2008. I hope this will be fixed in next version.


..yes, because the lines you draw are still not tangent, try drawing lines using "tangent" osnap, closer to the origin.

[Alan Cullen]

I agree with you, Bane, it is an annoying bug, and it happens way too often.

[hellnback]

I've had this problem many a time. Very annoying, sometimes it works othertimes it doesn't. As Alan said draw lines from the centre perp to the tan lines and trim to those.

[hellnback]

Also get a similar problem when trying to join arcs to a tangent polyline, for some reason it thinks that the end of the arc isn't on the end of the polyline, even though I just trimmed it. So I have to manually move the arc to the end.

*useless bit of random information*

[Alan Cullen]

hellnback,

Use multiple PEDIT with a fuzz factor of 0.001. That's what I do for that same problem.

Oh, dear, another aussie helping.... :twisted: :P

[hellnback]

hellnback,
Use multiple PEDIT with a fuzz factor of 0.001. That's what I do for that same problem.
Oh, dear, another aussie helping.... :twisted: :P

Yeah, I'm always having trouble with the FUZZ...:lol: