DI - shortening ARC
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Attach drawing files and screenshots.
Post one question per topic.
DI - shortening ARC
Now I want to shorten the total length of the arc to 2.8 with the green line pieces following the endpoints of that arc.
How does the DI (DIVIDE) protocol exactly work? shortening the arc piece shortens it one sided only. So I have to split in in halves and shorten the single halves?
How do I make follow the green pieces the endpoints of the arc?
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Christoph
Christoph
Re: DI - shortening ARC
Still not clear to me how to specify the entity that does the division. A point? A line?
Anyway, I divided, deleted the right segment of the arc, then shortened the left one (using the properties dialog), then mirrored the left and now it's looking like in the above screenshot.
Now, how do I snap the green lines to the arc endpoints of the red arc? The line pieces should stay with one point anchored at the circle ends (white circle) .
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Christoph
Christoph
Re: DI - shortening ARC
DI doesn't needs a previously selection. Just launch DI, select the entity which has do be divided and watch the mouse pointer - it will partly change to a dash dash point line which indicates the divide (or cut) position. That is as usual snap sensitive.
If I understand the task correctly then I would use the rotate tool for the green lines and then trim the white lines to merge again with the green lines. The Center point for the rotation is the center of the red arc.
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Re: DI - shortening ARC
Should 2.8 be the length or the cord of that arc? Can you attache an example dxf of this situation?
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Re: DI - shortening ARC
The greens are radii with a center.
Here appropriate 'moving' is to rotate.
You can select the uncut red and enter a new sweep angle or arc length in PropEdit.
Or, you can reduce/enlarge this arc in any way that suites your needs.
Symmetrically as your solution or not.
To alter the actual chord of the arc you need some contruction lines.
Cutting up the red might only serve something if you really need two co-radial arcs.
You'll end up with gaps or crossings as yours.
Done asymmetrical firts rotate your red by mouse around the center as you would like it.
Mid straight up in your case.
Now rotate the greens by mouse around the center so you rejoin them with the ends of the red.
The larger diam. is simply trimmed to the greens.
All that rotating requires lots off clicks.
Sometimes it may be easier to simply redraw new radii and trim them.
Regards,
CVH
Here appropriate 'moving' is to rotate.
You can select the uncut red and enter a new sweep angle or arc length in PropEdit.
Or, you can reduce/enlarge this arc in any way that suites your needs.
Symmetrically as your solution or not.
To alter the actual chord of the arc you need some contruction lines.
Cutting up the red might only serve something if you really need two co-radial arcs.
You'll end up with gaps or crossings as yours.
Done asymmetrical firts rotate your red by mouse around the center as you would like it.
Mid straight up in your case.
Now rotate the greens by mouse around the center so you rejoin them with the ends of the red.
The larger diam. is simply trimmed to the greens.
All that rotating requires lots off clicks.
Sometimes it may be easier to simply redraw new radii and trim them.
Regards,
CVH
Re: DI - shortening ARC
Despite of the fact that it was easiest to just delete the green lines and draw two new lines letting them snap to the endpoints, I'm passing the dxf anyway, maybe to learn a quicker way. Something like having the red point as center of rotation, grab the white line at the yellow endpoint let it snap to the magenta endpoint of the arc. The green lines are the desired result.
(N.B. in my example it wasn't that important whether it was the cord length or the arc length I wanted to reduce - it was neglectable in that case)
- Attachments
-
- chassis_bracket_experiment.dxf
- (106 KiB) Downloaded 314 times
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Christoph
Christoph
Re: DI - shortening ARC
Pls follow layer state setting mentioned in the drawing.
Regards,
CVH
PS
This makes a slot 2.8 wide.
The arc is not 2.8 long!
Regards,
CVH
PS
This makes a slot 2.8 wide.
The arc is not 2.8 long!
- Attachments
-
- chassis_bracket_experiment.rev.dxf
- (117.55 KiB) Downloaded 340 times
Re: DI - shortening ARC
I believe, I did not make clear enough, that the initial green pieces were not going to be radii pieces again.
They simply were intended to connect to the shortened arc ends.
But thanks anyway for the detailed work out.
They simply were intended to connect to the shortened arc ends.
But thanks anyway for the detailed work out.
Last edited by Krischu on Thu Sep 19, 2019 4:52 pm, edited 1 time in total.
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Christoph
Christoph
Re: DI - shortening ARC
Click them
Pick the end marker
Tow
Pick the end marker
Tow
Re: DI - shortening ARC
Thanks. That's exactly what I wanted to know. And where can read about the markers and their meaning? How to swap the meaning of the markers? What is the red and what the blue marker?
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Christoph
Christoph
Re: DI - shortening ARC
I read it in the QCAD Book ...
With the Reverse (RV) tool. But that is pretty irrelevant for CAD. If the drawing is meant for further CAM processing then we have a different story ...
Red = start, blue = end of the entity
Work smart, not hard: QCad Pro
Win10/64, QcadPro, QcadCam version: Current.
If a thread is considered as "solved" please change the title of the first post to "[solved] Title..."
Win10/64, QcadPro, QcadCam version: Current.
If a thread is considered as "solved" please change the title of the first post to "[solved] Title..."