# I want to make an arc from a fixed length in SketchUp web

I’m modeling a high tunnel. I want to use 8’ cow panels or make the arc. The width of the tunnel is 32’, and i want to see what kind of arc 6, 7, and 8 panels will make, so I can decide how many panels to use. So how can I make an arc that spans from one side to the other where the circumference of the arc is say 48’? Because I have 48’ of material to make the arc with? I want to set the circumference, not the angle.

If you go into the entity panel with your arc selected, it will tell you the length. There’s still some guessing, but it’s a start.

Edit:: here’s a guesswork arc, 32” base, 8(ish)’ circumference. (Not your exact measurements, but same principle)

I drew an arc that spans 32. (I used meters but the outcome is the same.)
In entity info I changed the sides to 6.
I measured 1 side and moved the top of the arc down to the point where 1 side was ~8.
Then I copied the arc to times and changes the number of segments to 7 and 8 and did the same until the segments were approximatly 8…

Arc fixed sides.skp (24,9 KB)
Edit: I just converted my drawing to Feet for your convienience…

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@dschips wants a 32 foot base, not inch…

Understood. I was just typing.

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