TANGENT

[malonicivil1]

hello, good morning

I would like to know if it is possible, in the creation of a family of Revit set parameters so that two circumferences be tangent to each other and for example, when changing the radius of one of them, automatically changes the radius of the other. Thanks a lot.

[RobDraw]

A couple of formulas in your parameters should get the job done. Your desired output will determine the complexity of these formulas.

Make a simple family and build on it. Start with two circles with the same radius. Decide on one to be the "master". Set the second radius to pull the radius from the "master". Also set a length between center points and make that twice the radius.

Next you can try to do the same with two different radii. This time the length will be the sum of the two radii.

Give it a shot and shar what you come up with.

[ToanDN]

There should be a tangent constraint icon where it occurs. Padlock it.

[barthbradley]

You mean this? 

[malonicivil1]

Hello, thank you for the idea but it´s not that case exactly...it is like that, what I want to do, 2 int tangent and 2 ext tangent. Any idea to relate those 2 radius? Thanks!

 

[malonicivil1]

sometimes it appears a symbol of tangent doing other tests but I can´t padlock it

[barthbradley · Accepted solution]

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@malonicivil1 wrote:

Hello, thank you for the idea but it´s not that case exactly...it is like that, what I want to do, 2 int tangent and 2 ext tangent. Any idea to relate those 2 radius? Thanks!

 

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This is how you build it: 

Get it?

"If you build it, they will come."  😉

[ToanDN]

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@malonicivil1 wrote:

sometimes it appears a symbol of tangent doing other tests but I can´t padlock it

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I was thinking about something else until seeing your screenshot.  See my response on the other thread of yours.

[malonicivil1]

hello, I have finally solved it, keeping the point of tangency in the same position and applying the formula:  DISTANCE BETWEEN CENTERS OF 2 CIRCUMFERENCES TANGENT INTERIORS = (R-r)* cos angle formed between the horizontal and the line that joins both centers with each other. I have managed to keep the points of tangency in their correct place. Thanks to everybody for the ideas!