## Tangents to a circle or arc

This section is for useful tips and tricks for Aspire

### Tangents to a circle or arc

Sometime my brain works sometimes it's just really slow..

Create the circle at the desired location
Draw two vectors from the center of the circle at the desired angle
Offset each vector the radius of the circle
Clip the unneeded part of the circle and you will have two vectors tangent to the circle

To create tangents to a center point arc draw temporary vector lines at 90° to the desired tangent lines
Create the center point arc
Draw vector lines snapped to arc ends at 90° to temporary vectors

Dale
You will get old if you live long enough!

Dale

dhellew2
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### Re: Tangents to a circle or arc

Good judgement comes from experience.

FixitMike
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### Re: Tangents to a circle or arc

Great tip, Dale. Thank you!
Michael Tyler

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### Re: Tangents to a circle or arc

FixitMike, Thanks, but I already have the tangent gadget and have used it.

It doesn't work too well to create tangents at a specific angle.
It only creates tangent vectors between two circles which can be made to work if the angle of the tangent lines are not critical, or by doing some trig calculations to size the circles and the distance apart necessary to achieve the desired tangent lines at specific angles.,.

Michael T, hope you can use it.

Dale
You will get old if you live long enough!

Dale

dhellew2
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### Re: Tangents to a circle or arc

The offset function is quite useful for this and other constructions. I often use it to construct a fillet between two arcs. Offset both arcs by the radius of the desired fillet, and draw a circle with the desired fillet radius centered where the offsets intersect, and then trim away. Sometimes you have to draw lines between the centers of the fillet and the original circles first, as the trim tool doesn't always recognize tangent points as intersections.
Good judgement comes from experience.

FixitMike
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### Re: Tangents to a circle or arc

Mike, Is this what you are creating? Dale

You will get old if you live long enough!

Dale

dhellew2
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### Re: Tangents to a circle or arc

Dale: No. Here's a picture of what I was describing.

Good judgement comes from experience.

FixitMike
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### Re: Tangents to a circle or arc

Thanks Mike, now there are a couple new uses for offsets. Dale
You will get old if you live long enough!

Dale

dhellew2
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