# Thread: Arc Length... How do you do it?

1. ## Arc Length... How do you do it?

Registered forum members do not see this ad.

Mmmmk. I have to put anomalies into a pipe at certain degrees and locations. I am given the OD, and the OD arc length distance from 0° to the anomaly. So what I do is trig and calculate the degree via "arc length=2πR*(C/360)". Get my angle, draw my line from center.

Is there any easier way of just placing an arc start point, the radius and how long you want it!?!?!?!

2. You can draw an arc of the radius needed, any length. Then use Lengthen command to set to actual length needed.

3. Do not remember in AutoCad but in DraftSight you can use DRAW -- ARC -- START END RADIUS which i think rkent is telling you.

4. Registered forum members do not see this ad.

if you are happy doing a bit of calculation, you could streamline getting the angle.

Divide the arc length by the diameter. This gives the angle in radians which you can enter when drawing your arc. Probably 4 decimal places is enough and put an "r" immediately after the numbers. AutoCAD will understand that the angle is in radians without having to change the angle units.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts