# Points for tangents to two circles

12 messages
Open this post in threaded view
|
Report Content as Inappropriate

## Points for tangents to two circles

 In case anyone finds it useful ... https://www.thingiverse.com/thing:2421943"Some simple OpenSCAD to get the points for lines that are tangential to two arbitrary circles. I found myself bodging this a lot so used Prof. Google to get some equations to do it properly. Enjoy!" _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 what is the prof google ? On 06/07/17 16:36, Ian Oliver wrote: > In case anyone finds it useful ... > > https://www.thingiverse.com/thing:2421943> > "Some simple OpenSCAD to get the points for lines that are tangential > to two arbitrary circles. > > I found myself bodging this a lot so used Prof. Google to get some > equations to do it properly. > > Enjoy!" > > > > _______________________________________________ > OpenSCAD mailing list > [hidden email] > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org_______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 On 2017-07-06 18:33, Mr C Camacho wrote: > what is the prof google ? Just googling for likely pages and my scad files link to the ones I used. I was really just flagging that the maths are stolen and I just did the monkey see, monkey do. _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 oh right! doh! I was thinking there was some soon to be shuttered google service that would take sets of data and produce a formula! On 06/07/17 19:31, Ian Oliver wrote: > On 2017-07-06 18:33, Mr C Camacho wrote: >> what is the prof google ? > > Just googling for likely pages and my scad files link to the ones I > used. I was really just flagging that the maths are stolen and I just > did the monkey see, monkey do. > > > _______________________________________________ > OpenSCAD mailing list > [hidden email] > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org_______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 I was trying to write a script to draw tangents of circles a while ago: http://forum.openscad.org/Script-to-replicate-hull-and-minkoswki-for-CSG-export-import-into-FreeCAD-td16537.htmlI can't remember where I got the maths from. Nophead supplied this very neat answer, that allows for different radii of the circles, and negative radii for concave shapes - hull and minkowski can't do that!: http://forum.openscad.org/Script-to-replicate-hull-and-minkoswki-for-CSG-export-import-into-FreeCAD-tp16537p16556.htmlIan
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 On 2017-07-06 22:52, droftarts wrote: > Nophead supplied this very neat answer, that allows for different radii of > the circles, and negative radii for concave shapes Wow, and very nice it is too. A neater way of creating the very shape I wanted from my tangent code, as it happens, and easier to use! _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 I use it for complex belt paths around different sized pulleys, for example an H-bot I a working on.On 7 July 2017 at 11:22, Ian Oliver wrote:On 2017-07-06 22:52, droftarts wrote: Nophead supplied this very neat answer, that allows for different radii of the circles, and negative radii for concave shapes Wow, and very nice it is too. A neater way of creating the very shape I wanted from my tangent code, as it happens, and easier to use! _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 Hi nophead Presumably you've added a bit to the script that adds up the length of the tangents, and the arcs of where the belt is on the pulley, to come up with the belt length? Ian
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 This post was updated on . I may be doing something similar here but in reverse? Finding the tangent points for two lines and a circle.
Open this post in threaded view
|
Report Content as Inappropriate

## Re: Points for tangents to two circles

 Yes I think you generate the same shapes but with different starting data.On 22 July 2017 at 13:41, irevdev wrote:I may be doing something similar  here but in reverse? Finding the tangent points for two lines and a circle. -- View this message in context: http://forum.openscad.org/Points-for-tangents-to-two-circles-tp21782p21898.html Sent from the OpenSCAD mailing list archive at Nabble.com. _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org