# Tangent between 2 Circles

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Is there a tool in CA that will automatically create a tangent arc between two circles...see attached pic?

I've tried the Arc Tool..."Start/Tangent/End Arc...but, either that isn't the correct tool or I don't know how to use it (very possible).

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1 minute ago, solver said:

Not sure I understand what you want to do, but maybe this video will help.

No...not "lines" between two circles.  I'm trying to draw a circle tangent to two circles.  I know how to do it the "long" way...just wondering if Chief has a tool like AutoCad..."Tangent/Tangent/Radius".  Which...with just a few clicks will draw a circle tangent to 2 circles.

Thanks!

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Speaking of "Circles".  Is there a way to draw a CAD Circle and as your drawing it specify either the exact radius or the diameter you want?

Let say I want a Circle 10' in diameter...I select the circle tool and draw, hit "tab"...and it brings up the "X" and "Y" dialogue box.  If I put 10' in both...I don't get a 10' radius or diameter.

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One extra click but I just open the Circle DBX and input what I want for radius or diameter.

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If you use the Circle about center tool, and hit tab as you draw you can select End Point Relative to Start and Polar and then your Distance Input is the Circle's Radius.

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When you say you know how to do it the "long way", I'm guessing you mean using the Geometric Construction method taught in Drafting School?

See attached plan.

Untitled 5.plan

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11 minutes ago, HamlinBC said:

When you say you know how to do it the "long way", I'm guessing you mean using the Geometric Construction method taught in Drafting School?

See attached plan.

Yes...but that was 1974.  Certainly there has been an advancement?

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33 minutes ago, Chopsaw said:

If you use the Circle about center tool, and hit tab as you draw you can select End Point Relative to Start and Polar and then your Distance Input is the Circle's Radius.

That's what I was looking for.  Thanks!

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Yes sir, chief has make "arc tangent" tool once you "lock centers" of the two arcs drawn over the two circles you want to locate their tangent arc. 3 clicks only!! May be I have to make a video, though I am sure you understood the point I am trying to make..

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Here is a crappy video. Hope sound is is OK this time, though English isn't my default language...

Any way, I hope that helps.

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This is what I'm talking about...can CA do this?

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Yes! Chief givis you the center of the tan tan circle automatic. The only difference  is AutoCAD does the circle for you, while in chief you have to draw the wide circle manually based on the auto center it gives you. The concept is there(shown in video above) and the same, but Hey that is AutoCAD and it is primarily for Cad works, Machine drawings etc...

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4 hours ago, HamlinBC said:

When you say you know how to do it the "long way", I'm guessing you mean using the Geometric Construction method taught in Drafting School?

See attached plan.

Nice illustration in your example plan.  Just one thing I think might be worth noting.  You don't actually need the 2 extra lines for trimming your circle.  If you've drawn the 3rd circle correctly, all you should need to do is group select the 2 original circles, click the trim tool, and then click it fence select the larger part of that 3rd circle.

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4 hours ago, yusuf-333 said:

Here is a crappy video. Hope sound is is OK this time, though English isn't my default language...

Any way, I hope that helps.

I watched...but it doesn't look automatic to me.

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5 hours ago, yusuf-333 said:

Here is a crappy video. Hope sound is is OK this time, though English isn't my default language...

Any way, I hope that helps.

4 hours ago, yusuf-333 said:

Yes! Chief givis you the center of the tan tan circle automatic. The only difference  is AutoCAD does the circle for you, while in chief you have to draw the wide circle manually based on the auto center it gives you. The concept is there(shown in video above) and the same, but Hey that is AutoCAD and it is primarily for Cad works, Machine drawings etc...

Good stuff Yusef.

For anyone having a difficult time hearing or understanding Yusef,  He basically demonstrated how to properly use (IMO) the Make Arc Tangent tool.  You essentially need to draw 3 arcs (the circles themsleves won't work).  There are ways to speed the process up a bit though using a different arc creation mode and a few other minor methods but the rules remain the same...That is, you need to use arcs to get any good automated tangent behaviors.  It would indeed by nice if Chief were to make a tool like this for circles as well.

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6 hours ago, Chopsaw said:

If you use the Circle about center tool, and hit tab as you draw you can select End Point Relative to Start and Polar and then your Distance Input is the Circle's Radius.

Yup.  Good advice Chop. If I might,  a few other things a person could also do that would allow them to use either of the 2 circle tools to enter either the radius or the diameter...

• If I person would like to enter a known Diameter using the Circle About Center tool, enter the desired diameter followed by /2 (divided by 2)
• If I person would like to enter a known Radius using the normal Circle tool, enter the desired radius followed by *2 (times 2)
• If I person would like to enter a known Diameter using the normal Circle tool, simply enter the desired diameter

It's obviously more efficient to just use Circle About Center if you prefer to enter a radius and the normal Circle tool if you'd prefer to enter a diameter but both can be done with either tool.  As Chop mentioned, the key is to use Relative To Start and Polar.

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It's obviously more efficient to just use Circle About Center if you prefer to enter a radius and the normal Circle tool if you'd prefer to enter a diameter but both can be done with either tool.  As Chop mentioned, the key is to use Relative To Start and Polar.

This would definitely save some time for repetitive tasks requiring many circles.  Especially when used with the General Preference of "Open Dialogs to the Last Panel Visited."

Thanks Michael.

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19 minutes ago, Chopsaw said:

This would definitely save some time for repetitive tasks requiring many circles.  Especially when used with the General Preference of "Open Dialogs to the Last Panel Visited."

Thanks Michael.

You're welcome.

BTW, here's a followup to Yusef's video with a couple added tips to help speed things up a bit...

Thanks again Yusef.  I really appreciate what you bring to the table here.

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You're welcome.

BTW, here's a followup to Yusef's video with a couple added tips to help speed things up a bit...

Thanks again Yusef.  I really appreciate what you bring to the table here.

Thanks Michael for the clarification and speeding up the process.

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You're welcome.

BTW, here's a followup to Yusef's video with a couple added tips to help speed things up a bit...

Thanks again Yusef.  I really appreciate what you bring to the table here.

Very clear Michael...thanks!

I do find it incredible that a software as powerful and fully developed as CA is...that this is the best and only way to accomplish this task.

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I used a mechanical design package over 20 years ago that had an easy way to get an arc tangent to two circles.  You identified the circles, specified the arc's radius, and, boom!  You would only fault out if the specified arc radius was too small.

But that was a mechanical design package.  In designing products, machinery, tools, and more, there is a regular need for this feature.

Not so much in residential architecture, unless you are using the software to model objects that are furnishings and fixtures.

I did not check, but I hope someone included this in the Suggestions area so Chief can see it clearly.  It ought to be easy to add.

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Helpful thread - thanks everyone.  What I wish we could do is set all arcs drawn in Chief to lock to center by default.  Is that possible?

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Very nice guys!   I have recently starting doing pool designs working with a pool contractor I have known for a while.   I have done it several ways but went back to using molding poly lines after I realized even the industry standard design tools like "Pool Studio" dont accurately model the bottom transitions.   I have done that in chief using terrain along with roads and curbs....but it is overkill and poly lines are easier to work.

Thanks for the tips given here....that will help a ton in workflow.   Here is a recent project all done in chief (modeled in lumion).   The design is actually a remodel.  The lower half of the pool already exists and we are adding spa/slide beach entry area.   I enjoy pushing the limits of what I can do in chief.

BTW....the slide is actually a staircase.  I just am only showing the "handrail" which I made a custom molding profile for the slide and altered my rise and run to get desired effect.   Wish we had a better 3d molding polyline that would extrude x,y,z but you can still do things....just takes a little head scratching.

[video]

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33 minutes ago, VisualDandD said:

Very nice guys!   I have recently starting doing pool designs working with a pool contractor I have known for a while.   I have done it several ways but went back to using molding poly lines after I realized even the industry standard design tools like "Pool Studio" dont accurately model the bottom transitions.   I have done that in chief using terrain along with roads and curbs....but it is overkill and poly lines are easier to work.

Thanks for the tips given here....that will help a ton in workflow.   Here is a recent project all done in chief (modeled in lumion).   The design is actually a remodel.  The lower half of the pool already exists and we are adding spa/slide beach entry area.   I enjoy pushing the limits of what I can do in chief.

BTW....the slide is actually a staircase.  I just am only showing the "handrail" which I made a custom molding profile for the slide and altered my rise and run to get desired effect.   Wish we had a better 3d molding polyline that would extrude x,y,z but you can still do things....just takes a little head scratching.

[video]

Cool!! Thanks for sharing Justin.