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# How to Draw Arc with Known 3 Parameters?

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dery
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Post Options    Thanks(0)    Quote  Reply Topic: How to Draw Arc with Known 3 Parameters?
Posted: 28.Jan.2024 at 08:07
I would like to ask technical drawing question.
How do you draw arc with radius of 400 that pass through point A and tangent to the Red line as shown in attached image?
Please show me the step-by-step and its construction geometry.

Edited by dery - 29.Jan.2024 at 01:20
dery
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Post Options    Thanks(0)    Quote  Reply Posted: 29.Jan.2024 at 19:46
philippe JOSEPH
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Post Options    Thanks(0)    Quote  Reply Posted: 29.Jan.2024 at 19:49
How to draw an arc with three known parameters ?
-1- Offset the red line by 400 on the lower side.
-2- Draw a circle of radius 400 centered on the point "A".
-3- Draw a circle of radius 400 passing by the intersection between the offseted red line and the circle centered on the point "A".
-4- Trim the circle on the red line and the green line and you have got your arc.
Kent Cooper
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Post Options    Thanks(0)    Quote  Reply Posted: 30.Jan.2024 at 15:43
 philippe JOSEPH wrote:....-3- Draw a circle of radius 400 passing by the intersection between the offseted red line and the circle centered on the point "A".....
... bearing in mind that there are two such Circles, and two resulting Arcs tangent to the red line through point A [unless point A is close enough to an end of the line that one of the tangency points would be off the end].
philippe JOSEPH
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Post Options    Thanks(0)    Quote  Reply Posted: 30.Jan.2024 at 17:24
Hello Kent and Dery, I have placed in the CAD/BIM Blocks library my file :
HOW TO DRAW AN ARC-PJH.dwg.
I see only one arc but I can be wrong.
dery
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Post Options    Thanks(0)    Quote  Reply Posted: 31.Jan.2024 at 08:55
 philippe JOSEPH wrote:Hello Kent and Dery, I have placed in the CAD/BIM Blocks library my file :HOW TO DRAW AN ARC-PJH.dwg.I see only one arc but I can be wrong.

Hi Mr. Joseph, can you create the CAD/BIM block that can be opened in AutoCAD 2014 please? Thanks

Edited by dery - 31.Jan.2024 at 09:37
philippe JOSEPH
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Post Options    Thanks(0)    Quote  Reply Posted: 31.Jan.2024 at 11:37
It's in the CAD/BIM BLocks : HOW TO DRAW AN ARC-PJH-2014.dwg
dery
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Post Options    Thanks(0)    Quote  Reply Posted: 31.Jan.2024 at 14:32
Hi Mr. Joseph. I saw your drawing already. However I still don't understand. How do you obtain those angles? Please advance and explain.
dery
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Post Options    Thanks(0)    Quote  Reply Posted: 31.Jan.2024 at 14:56
Hi Mr. Joseph, currently I am at this step (please see attached image). Can you tell me please what should I do for the next step? Thank you so much.

philippe JOSEPH
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Post Options    Thanks(0)    Quote  Reply Posted: 31.Jan.2024 at 17:41
Dery, the "step by step" method is in the CAD/BIM Block library.