concentric constraint problem in Hands On Exercise

[Anonymous]

Hello,

I am learning Fusion 360 by diving in to some demos and tutorials. I'm working on fully defining/ constraining 2-D sketchs. I am in this example:

"Learning > Sketch > Hands-On exercises > Fully-defining a Sketch > Steps 10 - 13" 

I am working on the example, and have set up the plate, the cut-outs and so-on. I have mirrored the cut-out across the construction line bisecting the plate. I am trying to apply a Concentric Constraint to the centre of the two arcs on either side of the cut-out, step 10 in the procedure. The Concentric constraint is greyed out., and I cannot invoke it at all. I've tried invoking it first5, then the centre-points, I've selected the centre-points and then tried to select the constraint, I've selected the arcs rather than the centre points, etc. but cannot get this constraint to stick. Any suggestions as to how to proceed?

Thanks! 

[ahreum.ryu · Accepted solution]

Hi @Anonymous, 

Welcome to the Fusion 360 community! 

when you want to add the concentric constraint, you should choose the circle line (not point). here is my video please take a look at this. 

As another workaround, you are able to choose point and add the coincident point.

I think it doesn't matter if you choose whether concentric or coincident. because our  purpose is to combine of 2 points. 

If you need more help, please let me know. 

Many thanks

[Anonymous]

Thanks Ahreum,

When I re-constructed the arcs using the  "Sketch > Arc > Three-point Arc" tool, it worked as per your video. My mistake was that I did the initial construction in my first trial using the "Sketch > L (Drag with Button-pushed)" to get the curved arcs. 

Dean