Techdraw dimension between line and arc tangent

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vectronic
Posts: 33
Joined: Sun Feb 18, 2018 9:44 pm

Techdraw dimension between line and arc tangent

Postby vectronic » Sun Apr 26, 2020 11:21 pm

Hello,

Is there anyway in techdraw to define a measurement as indicate by the red arrow on the attached annotated screenshot?

The best attempt I have had is to insert a cosmetic index (by eye) on the arc, and then do a measurement from the line to the arc - less than optimal. However for some reason I am now experiencing a bug where I can't seem to add a cosmetic index, so can't even do this...


Thanks very much.

Nick
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chrisb
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Re: Techdraw dimension between line and arc tangent

Postby chrisb » Mon Apr 27, 2020 12:40 am

You can do this in the model by creating appropriate seams. TechDraw is probably the wrong place to add such stuff (normal to circle and an edge - or should it be the center point of the line?).
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wandererfan
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Re: Techdraw dimension between line and arc tangent

Postby wandererfan » Mon Apr 27, 2020 12:59 am

vectronic wrote:
Sun Apr 26, 2020 11:21 pm
Is there anyway in techdraw to define a measurement as indicate by the red arrow on the attached annotated screenshot?
The best attempt I have had is to insert a cosmetic index (by eye) on the arc, and then do a measurement from the line to the arc - less than optimal.
@chrisb has it. When I need to do something tricky, I add construction geometry in 3D, then include it as Source for the View.
You can always hide the construction lines with the line decorator.
However for some reason I am now experiencing a bug where I can't seem to add a cosmetic index, so can't even do this...
details please. :) I don't get a lot of feedback on the cosmetic functions unless they crash.
vectronic
Posts: 33
Joined: Sun Feb 18, 2018 9:44 pm

Re: Techdraw dimension between line and arc tangent

Postby vectronic » Mon Apr 27, 2020 9:24 am

wandererfan wrote:
Mon Apr 27, 2020 12:59 am
details please. :) I don't get a lot of feedback on the cosmetic functions unless they crash.
With pleasure :-)

I have recorded my actions here to add a cosmetic vertex -> maybe I am doing something wrong? As far as I can see this isn't desired behaviour and I'm sure it didn't work like this previously.

https://www.loom.com/share/2a25b6f0fae9 ... b08f59a79b

I attach the cad file before the recording and after the recording.

Thanks
Nick
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example.FCStd
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example-after.FCStd
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vectronic
Posts: 33
Joined: Sun Feb 18, 2018 9:44 pm

Re: Techdraw dimension between line and arc tangent

Postby vectronic » Mon Apr 27, 2020 9:58 am

wandererfan wrote:
Mon Apr 27, 2020 12:59 am
@chrisb has it. When I need to do something tricky, I add construction geometry in 3D, then include it as Source for the View.
You can always hide the construction lines with the line decorator.
I have attached a screenshot of the sketch used to drive the geometry where I have a tangent construction line. I am using this to constrain the distance to the line. This constraint distance is what I am trying to expose in the techdraw drawing.

I must admit I am a bit clueless on how to proceed with your suggestion. I think instead of using a construction line, I think I would need to use external geometry in the sketch, but there is no external geometry to reference in this case.

The construction line done has a point on circle constraint as well, but I believe because it is a point on a circle, there is no edge at this point which appears in the geometry.

If you could provide any suggestions for how I should proceed it would be much appreciated.

Nick
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chrisb
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Re: Techdraw dimension between line and arc tangent

Postby chrisb » Mon Apr 27, 2020 11:22 am

The construction line doesn't contribute to the geometry as seen from the outside. You can create the circle from two arcs, that's what I did in my example. Similar with the line: split it in two tangential lines of equal length.
vectronic
Posts: 33
Joined: Sun Feb 18, 2018 9:44 pm

Re: Techdraw dimension between line and arc tangent

Postby vectronic » Mon Apr 27, 2020 11:26 am

chrisb wrote:
Mon Apr 27, 2020 11:22 am
The construction line doesn't contribute to the geometry as seen from the outside. You can create the circle from two arcs, that's what I did in my example. Similar with the line: split it in two tangential lines of equal length.
Thanks very much! Understood. I will give it a go.
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wandererfan
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Re: Techdraw dimension between line and arc tangent

Postby wandererfan » Tue Apr 28, 2020 1:16 pm

vectronic wrote:
Mon Apr 27, 2020 9:24 am
I have recorded my actions here to add a cosmetic vertex -> maybe I am doing something wrong? As far as I can see this isn't desired behaviour and I'm sure it didn't work like this previously.
Should be fixed by git commit 1fc2e755dd. Was not handling secondary views in projection groups properly.

Thanks for reporting!
vectronic
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Re: Techdraw dimension between line and arc tangent

Postby vectronic » Mon May 11, 2020 9:48 pm

wandererfan wrote:
Tue Apr 28, 2020 1:16 pm
Thanks for reporting!
Thanks for implementing!

I have taken the useful advice in this thread and re-done the sketch as two arcs and this indeed lets me add the desired measurement in techdraw. However it has has lead me to another unexpected issue in part design....

Now that the 'stud' is created by a pad of two arcs (instead of a circle) it seems I am unable to apply a fillet on the top curved edge of the 'stud'. I assume this is because a fillet on an arc is not possible, but it is allowed on a full circle...?

See screenshot.

Any suggestions how to paint myself out of this corner? :(
Screenshot 2020-05-11 at 22.43.02.png
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M4x
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Re: Techdraw dimension between line and arc tangent

Postby M4x » Tue May 12, 2020 8:10 am

Could you please provide your (example) file?

Thank you very much!