Place line tangent from the end of an arc

[MSSmith]

How does one draw a line tanget from the end of an arc.

 

I noticed the tangent snap stops at the end of the arc but one can still place a line beyond the end of the arc, thus no longer tangent.

 

Thanks.

[rkent]

1. Draw a line from the endpoint of the arc to the center point, draw a line perpendicular to the line at the end point. You can draw the line and move it, or have polar set to relative to last point, etc.

 

2. If the arc has just been drawn, start line command, hit enter twice, draw your line. If the arc was drawn previously, simply redraw the arc, start the line command, hit enter twice, draw line, erase arc.

[nod684]

you can also use UCS > OBject pick on the side / end of the arc where you want to draw your line, then draw your line

switch back to UCS > World when done

Edited November 29, 2012 by nod684

[rkent]

you can also use UCS > OBject pick on the side / end of the arc where you want to draw your line, then draw your line

switch back to UCS > World when done

 

That is a better solution, never thought the UCS would align to an arc that way. Thanks.

[eldon]

1. Draw a line from the endpoint of the arc to the center point, draw a line perpendicular to the line at the end point. You can draw the line and move it, or have polar set to relative to last point, etc.

 

If you were to alter the order that you drew the first line, that is from the centre of the arc to the endpoint, then your next line could be drawing the tangent itself.

[rkent]

If you were to alter the order that you drew the first line, that is from the centre of the arc to the endpoint, then your next line could be drawing the tangent itself.

 

Nice, makes things even easier, I still like the UCS the best.

 

Just beat it, beat it dead.

[CyberAngel]

1. Draw a line from the endpoint of the arc to the center point, draw a line perpendicular to the line at the end point. You can draw the line and move it, or have polar set to relative to last point, etc.

 

All this time I suspected there were tools I should have been using to do things like this. Apparently there aren't.

 

Another possibility for the OP is to start a polyline arc segment at the beginning of the arc, follow it (e.g. pick midpoint as second point), and go from there. The Polyline command gives you that tangent for the next segment by default. You can always come back and erase the first segment (or the original arc, which is now duplicated).

[Mike_Taylor]

Don't forget about geometric constraints.

[JD Mather]

All this time I suspected there were tools I should have been using to do things like this. Apparently there aren't.

 

Geometry Constraints (but they are kind of clunky in use in AutoCAD, fairly transparent in use in next-generation tools).

 

Mike beat me to it - but he didn't add pretty pictures....

 

[nod684]

That is a better solution, never thought the UCS would align to an arc that way. Thanks.

 

you're very much welcome