How to determine and design 2 arcs?
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How to determine and design 2 arcs?
Hi,
I would like to design the object shown in the attached picture.
I have begun with a sketch but don't know
* how to determine the radius of both arcs
* how to draw the arcs. 3 points are requested but I have only 2 (the end of the lines)
Kind regards
ProApe
I would like to design the object shown in the attached picture.
I have begun with a sketch but don't know
* how to determine the radius of both arcs
* how to draw the arcs. 3 points are requested but I have only 2 (the end of the lines)
Kind regards
ProApe
- Attachments
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- 20221002_110316_resized.jpg (456.18 KiB) Viewed 648 times
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- 2 arcs.FCStd
- (7.82 KiB) Downloaded 18 times
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- 2 arcs.JPG (26.58 KiB) Viewed 650 times
Re: How to determine and design 2 arcs?
You can draw the arcs using Sketcher Create3PointArc and then apply Sketcher ConstrainTangent between them and the lines to which they are attached. I attached the file with fully constrained sketch.
- Shalmeneser
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- Joined: Wed Dec 23, 2020 12:04 am
- Location: Fr
Re: How to determine and design 2 arcs?
* Draw an arc with its vertex coincident with the lines (Sketcher_ConstrainCoincident)
* add tangency between the line and the arc : Sketcher_ConstrainTangent
no need for dimensions.
* add tangency between the line and the arc : Sketcher_ConstrainTangent
no need for dimensions.
- Attachments
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- 2 arcs_SHALM.FCStd
- (5.81 KiB) Downloaded 14 times
- Shalmeneser
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Re: How to determine and design 2 arcs?
@NewJoker : Tangency is missing twice.
Re: How to determine and design 2 arcs?
Right, now it will be better:
- Shalmeneser
- Veteran
- Posts: 9474
- Joined: Wed Dec 23, 2020 12:04 am
- Location: Fr
Re: How to determine and design 2 arcs?
- Attachments
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- 2 arcs drawn 2_SHALM.FCStd
- (6.72 KiB) Downloaded 13 times
- thomas-neemann
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Re: How to determine and design 2 arcs?
here is a suggestion 1/2 minute (non-parametric draft /arch and part)
https://www.youtube.com/watch?v=SWrBDWnjETk
Re: How to determine and design 2 arcs?
Hello ProApe, greetings to the community!
One of the many other possibilities ....
- Attachments
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- 2 arcs drawn_domad.FCStd
- (8.87 KiB) Downloaded 17 times
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- 2 arcs drawn_domad.gif (486.81 KiB) Viewed 495 times
Re: How to determine and design 2 arcs?
Sorry, I had problems putting your numerous suggestions -for which I thank you very much- into practice. The GIF was very helpful (is there actually a way to control the playing of a GIF?). A video is of course even more practical, but I didn't recognise the method used in the video.
If I use the tool "Create an arc by its end points and a point along the arc" in the option "End points and rim point" at one of the two points and drag it over to the other I indeed get an arc with its central point, but how can I determine the correct arc diameter since I can move both and how can I fix them?
How can I change the appearance of the dimensions? I didn't find such a setting in the Preferences.
And where do I find a tool not to fix dimensions but simply measure dimensions?
If I use the tool "Create an arc by its end points and a point along the arc" in the option "End points and rim point" at one of the two points and drag it over to the other I indeed get an arc with its central point, but how can I determine the correct arc diameter since I can move both and how can I fix them?
How can I change the appearance of the dimensions? I didn't find such a setting in the Preferences.
And where do I find a tool not to fix dimensions but simply measure dimensions?
Re: How to determine and design 2 arcs?
based on your questions, it sounds like you have a misconception of how the sketcher works...
when you draw something (line, circle etc) in the sketcher there is no need to make this precise, actually it is more or less impossible to do...
you make it precise with adding constraints (like horizontal orientation, lengths, etc), also important is to make sure that points are connected (not visually on the screen, but that points have coincident constraint if they are supposed to be coincident).
maybe work through some of the basic sketcher tutorials on the wiki?
when you draw something (line, circle etc) in the sketcher there is no need to make this precise, actually it is more or less impossible to do...
you make it precise with adding constraints (like horizontal orientation, lengths, etc), also important is to make sure that points are connected (not visually on the screen, but that points have coincident constraint if they are supposed to be coincident).
maybe work through some of the basic sketcher tutorials on the wiki?