Autocad line arc intersection question

This is probably a dumb question but I'm new at using autocad.

I have a line and an arc that do not intersect. I want to move the
line in the a specified direction until it just touches the arc. I
don't know where the exact point of intersection will be on the arc or
the line. Is there a command I can use to do this?

 

Command Extend. Pick the object you want to extend to (your arc) and
then pick objects that you want to extend. (your line). works in
reverse of of trim. matter of fact if you had a second line that cross
the arc, you can trim the second line while in the extend mode by
holding the shift key. You can do the reverse while in the trim mode.
Just read your command line. it will tell you want to do.

 

Do you want to move it so the line IS crosses at a specific intersecting
point with the curve? If so mark the point somehow, and then move it. You do
know about OSNAPS don't you?

 

'Marking the point somehow' is the problem. I want to move the line
of arbitrary slope in a choosen direction, for example the y direction.
I want to continue to move the line until it just touches the arc of
arbitrary center and radius, I don't know exactly where the
intersection will occur on the line or the arc. I've looked at all the
OSNAPS modes but I don't see one that will work on its own. Maybe
there is not an easy way to do this or maybe I'm just having a brain
cramp. I can approximate by just moving closer and closer iterating to
a solution, but it is tiresome.

 

I don't want to extend, I want to move until the intersection occurs.

 

If you want to move a line so the end of the line touches the arc:

Start your Move command, pick the line -> Specify base point or
displacement: -> Type END -> Pick the END of the line -> Specify second
point of displacement -> Type INT -> Pick the line, then pick the arc.

If you want to move the line so it keeps the same slope, but touches the
arc at some arbitrary point, instead of typing the INT, type NEA, and
then pick the point on the arc where you want the line to touch....

Steve R.

 

ALIGN, with 1 source point & 1 dest. point

 

That's still not it. The second is close but if I pick the point on
the arc and the slope remains then it will likely cut the arc at two
places like a cord. I want to pick a 'direction' for the line to
move, for example the y direction or x direction, then move the line in
that direction until some point on that line touches the arc. Only one
point of intersection.


Here is a design example: suppose you had a plan for an irregularly
shaped curved building. Suppose there was a street running in front of
the building and you wanted to build a sidewalk parallel to the street
but also touches the building at just one point. So you draw a line
parallel to the street then move it in a perpendicular path to the
street until it first touchs or intersects the building.

 

So work backwards:

Start a line from the center of your arc to PER (perpendicular) to the
line that defines the centerline of your street. Where that line crosses
the arc is the point where your parallel sidewalk line should touch the
building.

 

YES! That's it. Whew, problem solved, thank you very much.

 

I have to say that you haven't been making it easy for us to understand what
it is that you want to do.

For this last example do the following:

Method 1:

Draw any line perpendicular to the street on either side of the building.

Draw a line from a TANGENT to the curve to the PERPENDICULAR of the line.

Extend/offset the line as required.

Method 2: (assuming the curve is an arc)

Set your UCS to the street line.

Draw a line from the QUADRANT of the arc with ORTHO on.

Extend/offset as required.

 

Welcome.

 

I apologize for not being clear.

The post by Mr. Steve Rauenbuehler worked perfect for what I am trying
to do.

I'm actually working on guitar body shapes not a sidewalk, but that
example would have been even more confusing than the one I already
gave.

Thanks