How do I constrain this circle to the mid point

[matthewpolack]

Hi,

I'm trying to constrain this circle to the mid point of the shape below...so that if I make the larger rectangle wider...the circle stays locks to the centre. No matter what I try..the circle stays where it is...and the rectangle moves wider...how can I lock these together?

https://a360.co/3a5Kil4

Thanks for any clues on how I would do this!

[jeff_strater · Accepted solution]

for just this part, you need a Coincident constraint between the circle center and the construction line:

But, as you can see in the screencast, that ONLY fixes one issue.  You will need additional constraints and dimensions to make this entire sketch fully parametric.

[matthewpolack]

Thanks so much for the reply. I'm struggling a bit to get my head around these constraints...I can see I need to lock everything down as much as possible from the start in their overall positions...as later on it becomes a bit of a 'constraint' puzzle. Thank you! Appreciate the tips!

[hamid.sh. · Accepted solution]

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@matthewpolack wrote:

... I'm struggling a bit to get my head around these constraints...I can see I need to lock everything down as much as possible from the start in their overall positions...as later on it becomes a bit of a 'constraint' puzzle...

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That's why it is recommended to make the sketch as simple as possible. your sketch is way too complicated and crowded. You'd better avoid offset, fillet and mirror in sketch and leave them to solid or surface.

[davebYYPCU · Accepted solution]

Quick basic sketches are easy to read, fillets in the modelling window,

use Origin for Symmetry, 

Basic sketches makes for shorter timelines too.

Might hep....

[matthewpolack]

Thanks! Great tips.

[matthewpolack]

Thanks for that! Good to know!