Re: Formula for percentage arcs anyone?

From: Don Slusarczyk <don_at_slusarczyk.com>
Date: Wed, 04 Sep 2013 00:20:04 -0400

Mike,

In ACAD all you have to do is first draw a horizontal line that is the
length of your chord. Say 5", so draw a 5" horizontal line. Then if you
want a 5% arc then .05*5 = .250" so use the ACAD command "OFFSET", enter
the distance of .25" then select the line, then to offset the line, just
select an area above the line to offset in that direction. Now you will
have two parallel 5" long lines 0.25" apart. Then use ACAD command
"ARC", the start point will be the front of the lower line, then select
the midpoint of the upper line as the second point, then select the end
of the lower line as the end point. It will create the arc containing
those three points. Then just delete the horizontal lines and you will
be left with the 5% arc.

Don
>
> Greetings.
>
> I am trying to reproduce a 5% airfoil in AutoCAD and I'm not having a
> lot of luck. Everything seems to default to degree arcs, which isn't a
> problem, however I cannot find a formula to convert between the two.
>
> Anyone have the formula handy?
>
> Regards.
> Mike Kirda
>
Received on Tue Sep 03 2013 - 21:19:31 CEST