topic Find sketch objects centre point in Fusion Support Forum

Find sketch objects centre point

ssashton — Fri, 17 May 2019 17:00:17 GMT

Hi Guys,

I hesitate to ask this because it must ave been answered already but I have done a Google search and also watched an umber of Lars' videos and am still at a loss.

How do you quickly find the centre point of a number of sketch objects and pick it up for alignment purposes?

For example I have a pattern of 4 circles that I want to align with centrally to a rectangle (holes in the corners of a plate). I can use dimensions but that's a pain.

In AutoCAD this would be simple - draw a line between each diagonal and then it will automatically pick up the line intersections as a move point. That doesn't work for me in Fusion, unless I specifically draw a point on the line intersections first. It doesn't allow me to select line intersections by default. Is there some sensible reason for this I'm missing?

Also, what if the centre point is not so obvious like a wiggerly pattern that needs to be positioned inside a rectangle. Is there an easy way to position the shape inside the rectangle so it has an equal amount of space around the extremities?

Thanks!

Re: Find sketch objects centre point

HughesTooling — Fri, 17 May 2019 17:40:58 GMT

It looks like you have an L shape between 3 of the holes to maintain their positions, so draw one diagonal line then use a midpoint constraint, select the diagonal line then the centre point of the rectangle. Might want to make the diagonal line a construction line.

Mark

Re: Find sketch objects centre point

HughesTooling — Fri, 17 May 2019 17:46:25 GMT

@ssashton wrote:

Hi Guys,

Also, what if the centre point is not so obvious like a wiggerly pattern that needs to be positioned inside a rectangle. Is there an easy way to position the shape inside the rectangle so it has an equal amount of space around the extremities?

Thanks!

To answer your last question. It depends on what the geometry is made up from. You can draw a rectangle roughly around the geometry then add constraints, for arcs add tangent then coincident for lines but the problem comes with splines as you can't add tangent constraints. Have you got an example.

Mark

Re: Find sketch objects centre point

ssashton — Tue, 21 May 2019 13:37:01 GMT

Thank you! Your answer was very helpful.

If I draw a center rectangle the center point is already there. If I draw a 2-point rectangle it is not.

Is there a way to find the center of a 2-point rectangle without needing to draw a line between each corner?

Re: Find sketch objects centre point

HughesTooling — Tue, 21 May 2019 13:47:59 GMT

There is but it depends if you have a point to constrain too, you will need to create 2 Horizontal\Vertical constraint though.

If you select the Horizontal\Vertical constraint then select the point you want to constrain too then press Shift and hover over the midpoint of a line you should be able to select the midpoint to add the first constraint, then repeat for the other direction.

Should end up like this. You need to select the midpoint on the line second. I just found a bug where it fails if you select the line midpoint then the centre point.

Mark

Re: Find sketch objects centre point

g-andresen — Tue, 21 May 2019 14:00:08 GMT

Hi Simon,

try it this way:

günther

Re: Find sketch objects centre point

HughesTooling — Tue, 21 May 2019 14:08:22 GMT

@g-andresen You still need to add constraints though.

Here's a screencast I made to report the bug. Second half shows how to constrain to a point, after 25 second point.

Mark

Re: Find sketch objects centre point

g-andresen — Tue, 21 May 2019 14:59:22 GMT

Hi Mark,

to find the center, you don't need any constraint but only if it is to be determined.

günther

Re: Find sketch objects centre point

ssashton — Mon, 10 Jun 2019 13:56:27 GMT

What exactly is the SHIFT key doing here?

Re: Find sketch objects centre point

HughesTooling — Mon, 10 Jun 2019 14:06:38 GMT

The shift key enables midpoint constraints.

Mark