How do I find the 16 needed constraints

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keithsloan52
Posts: 1091
Joined: Mon Feb 27, 2012 5:31 pm

How do I find the 16 needed constraints

Post by keithsloan52 » Tue Jan 14, 2020 7:47 pm

See attached file
Hide_Door2.FCStd
(7.1 KiB) Downloaded 15 times
drmacro
Posts: 306
Joined: Sun Mar 02, 2014 4:35 pm

Re: How do I find the 16 needed constraints

Post by drmacro » Tue Jan 14, 2020 7:57 pm

The number/word "16 degrees" is clickable.

When you click on it, the objects that are not constrained are highlighted in green.
openBrain
Posts: 3089
Joined: Fri Nov 09, 2018 5:38 pm

Re: How do I find the 16 needed constraints

Post by openBrain » Tue Jan 14, 2020 8:35 pm

First, there are a lot of 16-constraint sets that work. Also there a lot (much more) that don't work. :)
Then FC by itself will not make it magically happen for you. This is human cleverness to find which set is correct and fits what you want.
You need to learn and practice to gain skill/knowledge/know-how. ;)
However having good geometry knowledge ease things. Reading chrisb's tutorial is also a good entry point to understand DoF concept (as applied in solver of sketcher).
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bejant
Posts: 6059
Joined: Thu Jul 11, 2013 3:06 pm

Re: How do I find the 16 needed constraints

Post by bejant » Tue Jan 14, 2020 8:56 pm

The endpoints of the upper 2 inner rectangles are missing some Coincident Constraints:
20200114a.png
20200114a.png (2.6 KiB) Viewed 249 times
keithsloan52
Posts: 1091
Joined: Mon Feb 27, 2012 5:31 pm

Re: How do I find the 16 needed constraints

Post by keithsloan52 » Wed Jan 15, 2020 8:19 pm

Okay I got down to seven, but now seem to be stuck
Hide_Door2.FCStd
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drmacro
Posts: 306
Joined: Sun Mar 02, 2014 4:35 pm

Re: How do I find the 16 needed constraints

Post by drmacro » Wed Jan 15, 2020 8:54 pm

The reason you are stuck is many of the end points of your geometry were not coincident and thus were not constrained as yet.

I would recommend you use the rectangle tool to draw rectangles, it will produce rectangles with coincident corners.

I have attached my take on what you are attempting, just for reference.
Attachments
Hide_Door2-mac.FCStd
(7.5 KiB) Downloaded 6 times
openBrain
Posts: 3089
Joined: Fri Nov 09, 2018 5:38 pm

Re: How do I find the 16 needed constraints

Post by openBrain » Wed Jan 15, 2020 10:00 pm

You can use the Sketcher ValidateSketch tool to find open vertices and missing coincidences. ;)
keithsloan52
Posts: 1091
Joined: Mon Feb 27, 2012 5:31 pm

Re: How do I find the 16 needed constraints

Post by keithsloan52 » Wed Jan 15, 2020 10:36 pm

Thanks
keithsloan52
Posts: 1091
Joined: Mon Feb 27, 2012 5:31 pm

Re: How do I find the 16 needed constraints

Post by keithsloan52 » Thu Jan 16, 2020 6:11 pm

Okay I am now trying to make two circular holes in sketch001.
Hide_Door2-A.FCStd
(26.76 KiB) Downloaded 11 times
They seem to display as construction lines and I try toggle them.
Or do I need to drill them separately?

Thanks
drmacro
Posts: 306
Joined: Sun Mar 02, 2014 4:35 pm

Re: How do I find the 16 needed constraints

Post by drmacro » Thu Jan 16, 2020 6:27 pm

When the lines of a sketch are blue, that means they are construction geometry. Choose
Toggel_construction.png
Toggel_construction.png (950 Bytes) Viewed 103 times
to toggle from/to construction mode.
door_w_holes.png
door_w_holes.png (3.34 KiB) Viewed 103 times
Attachments
Hide_Door2-A-mac.FCStd
(29.33 KiB) Downloaded 2 times
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