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How to align rectangle with the path of a circle

gary_smith251gary_smith251 Member Posts: 9

Hey Folks, Just getting started with oneshape and cant seem the find the correct search terms to solve my problem

Im designing a simple bearing mount for use in a turntable that will follow a set curve, so to do this i created a construction line circle with the rails diameter of 325mm, I then used this to sketch the block so that it rides over this circle, all good. Now when trying to add a cutaway for the bearings to sit into im struggling to find the correct method of constraint to align the cut out with the rail without overconstraining my sketch.

Perhaps im doing this all the wrong way but the best way to learn is usually by doing it wrong.

In the below image the im thinking the midpoint of the line should be constrained to the contruction line of the circle rotating the part to the correct orientation, or is that thinking all wrong?

I have tried adding a point and constraining that but that did not work.

https://cad.onshape.com/documents/5d7cd2dc6f4d13b8c91dfc3c/w/8db3dc82ad6a4bc8fe9949f2/e/1f21e07c509c63703a525865?renderMode=0&uiState=66e40631471afc7f2e86e191

Best Answer

  • glen_dewsburyglen_dewsbury Member Posts: 822 ✭✭✭✭
    Answer ✓

    You're trying to run over a horizontal constraint. Remove this and the coincident between midpoint and arc will work.

Answers

  • robert_scott_jr_robert_scott_jr_ Member Posts: 508 ✭✭✭

    Hey Gary. Please make your document public. Right now we can't see what constraints your sketch has. Do I understand correctly that you want the centers of the two short sides of the rectangle to be coincident with the circle? - Scotty

  • glen_dewsburyglen_dewsbury Member Posts: 822 ✭✭✭✭
    Answer ✓

    You're trying to run over a horizontal constraint. Remove this and the coincident between midpoint and arc will work.

  • gary_smith251gary_smith251 Member Posts: 9

    Sorry Scotty thought that was done via the sharing link, please try this one

    Bearing Block

    Im still strying to wrap my head around the nomeclature so if coincident means that the centre point of both short edges are alligned to the arc of circle then yes that is what im trying to acheive. in my head this would mean the centre line of the bearing should reside directly on the rail

    this is the part im trying to replicate as thought it provides a simple enough challenge to learn the fundementals whislt doing the training course. as you can see the bearing is at an angle so that it runs true on the circular rail below it

  • gary_smith251gary_smith251 Member Posts: 9

    Hi Scotty,

    https://cad.onshape.com/documents/5d7cd2dc6f4d13b8c91dfc3c/w/8db3dc82ad6a4bc8fe9949f2/e/1f21e07c509c63703a525865?renderMode=0&uiState=66e41c28b9fa683c1c7e5fa5

    please try that link, think that should solve it. Im still trying to wrap my head around the nomenclature but if coincident means that the midpoint of the two short sides align with the arc of the circle then yes that is what i'm trying to acheive

  • robert_scott_jr_robert_scott_jr_ Member Posts: 508 ✭✭✭

    Yep. Link works. Glenn has got the fix and explanation. Yes, coincident is:

    occupying the same place or position

  • gary_smith251gary_smith251 Member Posts: 9

    Thanks guys I really appreciate the assist. I'm assuming that constraint is added as part of the centre point rectangle sketch as I don't remember adding it myself

    Either way got the part finished and printed tonight and seems to function fine, just need to test fit it now and modify to suit

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