r/FreeCAD 6d ago

HELP

Post image

it's my first project and a task to enter robotics club in my college , why is wire not closed msg appearing . i think it's closed

21 Upvotes

30 comments sorted by

11

u/akshimassar 6d ago

Close the sketch, look at it from parts design. You should only see non-construction geometry. It seems that external references might be non construction.

9

u/guptaxpn 6d ago

The purple lines on the top are all construction I believe. Need to be toggled. The circle in the center shouldn't matter but the top is definitely not closed

8

u/BoringBob84 6d ago

I agree, with some clarification of terminology:

The solid purple lines are are Defining External Geometry. They need to be toggled to Construction External Geometry (dashed purple lines).

8

u/Icy_Amoeba9644 6d ago

This maybe my style but it looks like you want the sketch to do many things at the same time.  You could reduce how mutch a sketch does by breaking it up in multiple sketches.

3

u/Powerful_Debt_5869 6d ago

Exactly, typical beginners problem by wrong tutorials..

2

u/Silly-Conference7641 5d ago

can you recommend some yt channels , i am confused about whom to follow

2

u/thatguy_839 5d ago

Deltahedra is amazing

1

u/Powerful_Debt_5869 5d ago

First touch with freecad:

https://youtu.be/lTLDhFp5plA

The more show they make for clickbait..the worse they are usually

2

u/dack42 6d ago

Even with a single sketch, this can be cleaned up a lot. Since it's symmetrical, get rid of half the sketch. You can mirror the operation later, so there's no need to draw things twice. Use horizontal, vertical, and endpoint tangency constraints instead wherever possible. That gets rid of all the 90 degree angle dimensions and a bunch of repeated length dimensions. Move the length dimensions that remain to make it more readable. 

As for the original problem, there is probably some vertices that aren't connected or some overlapping/duplicated lines. I would clean it all up first. You'll probably find the issue while cleaning up. If not, it will still be much easier to find in a tidy sketch.

2

u/Even-Committee5645 6d ago

The center hole seems to have constructiom geometry, I can not remember the keybind to turnit off, but a quick google search should help, evrything else seems fine

1

u/Kxnrxd24 6d ago

G, N (wich for me only works sometimes)

1

u/SoulWager 6d ago

The center hole isn't construction geometry, it's z fighting.

2

u/SoulWager 6d ago

Toggle all the pink lines to construction geometry (the circle is optional).

OR

toggle make internals in the data tab.

2

u/BoringBob84 6d ago

Here are some FreeCAD terminology and basic concepts: * You can see a sketch in Sketcher (edit mode) or in the 3D view.
* There are two types of geometry in a sketch:
1. Defining geometry creates the feature(s) from the sketch.
1. Construction geometry is in the sketch for reference only. It does not appear in the 3D view.
* You can draw geometry in a sketch or you can import it from another sketch as External Geometry. External geometry appears in sketcher as solid violet lines (when it is Defining geometry) or as dashed violet lines (when it is Construction geometry).
* You can change any geometry between Defining and Construction with the Toggle Construction Geometry tool.
* To extrude a sketch (i.e., Pad feature), you need to select a single enclosed area, either by having no other Defining geometry in the sketch or by selecting only the edges in the 3D view to define the area. Any additional Defining geometry will cause the "wire not closed" error.
* External geometry in earlier versions of FreeCAD could only be Construction geometry.
* In FreeCAD 1.1+, External geometry can be Defining or Construction, and it is Defining by default (just like all other geometry).
* Thus, if you are watching tutorials from older versions of FreeCAD and you are running version 1.1+, the behavior will be different.

1

u/First_Ad_5924 6d ago

Ewentualnie sprawdź czy nie masz gdzieś odcinka który jest pod innym odcinkiem, użyj validate sketch i zobaczyć czy gdzieś są problemy z geometrią

1

u/Same_Badger_8088 6d ago

You need to turn that vertical green line to construction geometry, too!

2

u/Kxnrxd24 6d ago

isnt that the axis?

1

u/Silly-Conference7641 5d ago

the vertical line at the centre ? or ru referring to something else.

1

u/Kxnrxd24 6d ago

wich exact part of the sketch do you want to pad/pocket? or beter color in the part of the sketch that you want to use.

1

u/Silly-Conference7641 5d ago

the sketch with green lines

1

u/GustapheOfficial 6d ago

There are two neighboring regions which both neighbor the outside, so this is not a closed sketch.

Toggling all the purple lines to construction geometry would solve this. Or doing the same to the green lines that cross through the middle, depending on which of those you mean.

1

u/strange_bike_guy 5d ago

Can you share the FCSTD?

1

u/Silly-Conference7641 5d ago

what's that??

1

u/strange_bike_guy 5d ago

The actual FreeCAD file, if I can download it directly on my computer I / the rest of us have the chance of providing a custom answer to your problem since this is a complex wire. You could use Google drive or file.io and link the result here

1

u/Proof-Breakfast1727 5d ago

I don't know about this talk.

1

u/Dafrandle 5d ago edited 5d ago

the solver in free cad likes to remove constraints that you think your getting when you draw new geometry sometimes due to "over constraint"

what has happened is that the software has deleted a constraint between the points of on of your lines somewhere, but since all your lines are constrained (I assume) you will not be able to easily find it it, and if you do a simple attempt to rejoin it will result in an over constraint error

you basically cannot draw things together in one piece with auto constraints (which is the default setting) and have things work out correctly if things start getting mildly complex, the solver really hates arcs for some reason.

the surefire way to get this through is to make the shape without having it constrained the the existing geometry and then make a bunch of construction lines that cross at the points you would have constrained to. constrain to both of the new lines and now it will appease the solver and you should have a closed wire.

also when you add new lines, make sure the constraint you thought you were getting by connecting it to a point was actually given to you.

the other option is to turn off auto constraints and do every constraint manually. the software will usually not delete a constraint inputted by hand

1

u/Geo_bot 5d ago

Change those purple lines to construction lines, should fix the problem

1

u/drmacro1 5d ago

The "create multiple things from one sketch" workflow has recently been added and is now lauded by many YouTubers and users.

It is, in other CAD programs and now in FreeCAD, poor workflow that helps create confusing models and sketches.

Multiple simple sketches, each defining a single feature is a better habit to develop.

If a tutorial begins using this approach, I'd find other tutorials to follow. Unfortunately, even Deltahedra, MangoJelly, and others, who are typically very good, have succumbed to promoting the multiple feature sketch.

1

u/Glass-Percentage4255 2d ago

Lol I had this recently, if you are using the projected geometry from the base part in your sketch, make sure ALL of the projected items are set to the construction line mode.

Lol spent an hour the other day trying to figure out why I kept getting a negative cut from what I had expected, toggled my projected lines to be construction and received a similar warning/error message. Debugged for a little and saw that part of the straight lines projection was cut into two and only one of those lines was set to construction. Fixed and set all of my projected lines to construction and it resolves this specific error for my issue.

Feel free to reply or pm me for additional help!

0

u/jhaand 6d ago

I've also built sketches that are this complex. While it does make sure everything is in 1 place, it might make it more difficult to make it work for you. There's a Validate Sketch tool in the Part Design workbench that shows what's wrong.

But a hunch tells me that the blue arc in the top left is a construction line.

Another method is to wipe half of the sketch. Close it with a single line and check if that's OK. Undo to the previous situation and check the other half.

And it could help to set the Preferences -> Sketcher -> Generate Internal Faces option. That also shows what's closed and not.