Draw an arc of a specific length

I need to draw an arc that has a radius of 96" and is 16" long. I can get it done but with a complicated work-around and figure there must be a better way. I learned some helpful things about arcs by reading posts when I searched the topic but didn’t find anything that answers this question directly.
Thanks in advance for any help…

It sounds like you need an extension called Arc Tools from the Sketchucation Plugin Store. It has a number of options for drawing an arc including one for drawing arcs of given radii and lengths.


That is the exact operation I’m looking for… thank you! There’s getting to be a well-worn digital path from my computer to the Plugin Store! BTW what other features of the Arc Tools plugin do you find yourself using?

Glad that helps.

I guess I don’t really use any of them but I remembered there was an extension. I had to hunt it up this morning and install it so I could make the GIF.

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I’m going to do a tutorial for my Digital Jobsite Channel about framing round walls with a conical roof for a ‘turret’ room and need to get stud spacing accurate for exterior sheathing and this is just the ticket!

I downloaded this tool, but it doesn’t let me edit the arc length to a specific value, either while I’m drawing it or after it has been drawn. I can edit the number of segments and the radius, but not the length. It’s not greyed out, but when I click into the length box, it won’t accept my value.

In fairness, the extension is about 5 years out of date, so there’s a chance it just doesn’t work with SUPro 2019, which I’m using.

Arc length isn’t editable in the Entity Info panel. You would need to enter the value while drawing the arc. Make sure you aren’t clicking in the Measurements window before typing the value.

I just installed it in SU2019 and it works fine for me.

DaveR, while drawing an arc, once I’ve clicked on the radius point then clicked on the length point and begin the third part of the process (dragging out the arc) the measurements box is showing degrees rather than length. I can enter 12’ or whatever, but it doesn’t draw a 12’ long arc. What am I missing?

From your description it sounds like you’re selecting the wrong option from the menu. Make sure you are selecting Arc:Center, 1 Point, Length and not Angle.

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Fabulous… that worked! Thanks so much DaveR!

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