Sketch Instabilities

[barrykingwill]

Sketch Instabilities

My instability woes continue.

You may recall a short while back I claimed that referencing a plane, or creating a new plane and copying a sketch onto it, put the new sketch in a totally different location (but on the plane)

Now I have often copied onto new planes where it has worked, but there seems to be some instability in the process.

I now worked out that the way off the model was actually mirrored about (in my case) the X axis.
So I set about mirroring it back, so as to get the sketch where I initially intended it to be.

See the following screen capture immediately before the mirror action. You can also see the outline of the source sketch from where it was copied (in the place we I intend it to mirror back to.)

Next see a close up of the sketch so as to familiarize oneself with the shape.

Next see the preview of the mirror, in which all looks normal

Next see the mirrored sketch (and for that matter the original sketch too, at the bottom of the screen)

Note it has become corrupted.

Lastly we delete the original, from whence you can get anything from what you expect, like

or even the following "dogs breakfast"

The last "effect" happened merely as a result of deleting the original sketch (but it did not always happen...a couple of undo's got me back to the correct original, but the same mirror process ended up with the former (almost correct) effect.[/img]

 

[marm37co]

My instability woes continue.

:shock:

Your sketches haven´t all restrictions. Some lines haven´t the horizontal and vertical restrictions, for example. This can cause the error. You view the DOF remaining. This value must be equal o about to zero to obtain better results in your problem.

If you want copy various sketches use the option copy in the sketch menu or use the feature catalog.

I think that in sketches Alibre is good.

 

[barrykingwill]

Thanks for the reply.

I am not saying sketches are not good in Alibre.

This is the first time this has happened, and I have created many sketches. I also use the copy function all the time, but one cannot use copy when you want mirror (you will notice this sketch is not symmetrical in any direction, so I have to use mirror. I have also used mirror many times without a problem.

Normally when you copy a sketch from one plane to a new plane (even a nun fully constrained sketch) it normally puts it back in the same place (when the planes are parallel to each other). In this case it mirrored the sketch of its own accord. Hence I set about mirroing it back, and that process failed as shown above.

This sketch comes out of a model which is showing other instabilities in the features, which Alibre support are looking into, but this specific sketch modification was done on an older version (thought to be stable).

 

[cherkey]

You should try the auto dimension (Sketch|Auto Dimension...) before the Mirror operation. It should help 'hold it all together'
I find that to be a very helpful tool...
Chris

 

[swertel]

When you post images, could you please make sure that they are 640x480 or less. This thread takes a very long time to load.

The better netiquette would be to start your problem here, state that you'll post images in the BINARIES group to illustrate your point. Further discussion can than be in the binaries or this group. With a real newsreader, this technique is much easier because you can send your post to two groups at once, but please keep in mind the people with dial-up connections when attaching images to threads.

 

[barrykingwill]

Scott

Do you really expect people to bounce back and forth to look at images in the binaries section, which is in another location of the forum.

I fully agree to use it for 1 image or for step files etc.

Just opening another section of the forum can take me 30 to 40 seconds, and then I need to do that for every image.

I certainly would not bother.

Also you cannot add text between images to explain what you mean if the images are not with the text.

It takes long enough to upload them onto another site and reference them in this thread. It took me about 30 minutes to post that thread, including making the files and uploading them to an independant server. However I will endevour to make the image smaller.

I guess another alternative is to put it all in a WORD or PDF file, and past the URL link. That might be more clinical.

Actually thinking about it, that is what I will do next time, for long illustrated explanations. Use an external file with an URL for access.

Regards

barry

 

[barrykingwill]

Re:

You should try the auto dimension (Sketch|Auto Dimension...) before the Mirror operation. It should help 'hold it all together'
I find that to be a very helpful tool...
Chris

Chris thanks for this tip.

I immediatly tried it on this sketch (well an uncorrupt version of it)

It has locked Alibre up solid (in computation) for the last 45 minutes. I guess I should have tried it on a simpler sketch first. Did not realise it was such a labour intensive operation.

But thanks for the tip. I tend to manually dimension what is needed, and not dimension what is not needed.

 

[barrykingwill]

Re:

It has locked Alibre up solid (in computation) for the last 45 minutes.

Hey... a cup of coffee (actually almost beer time here) later and a yak with a colleague, and I cam back and it was finished. Took about 55 minutes, I guess....did not specifically time it.

Can barely see the sketch for all the dimensions, bet hey, it did it.

Impressed.....not by the time, but by the result.

 

[cherkey]

Hey, did the Mirror operation work then?
Chris

 

[barrykingwill]

I did not mirror it.

This model seemed to have feature related instabilities / corruptions too, so I went back a few versions, and used the auto dimension on the older versions's sketch.

In that case, when I transferred the reference of the plane (of that sketch) from a face (which I was about to delete) to rather reference another plane) and then the sketch actually remained in the same place and did not self mirror, as was the case illustrated here, so all was sorted.

So I did not have to mirror it cos it did not move of its own accord.

 

[cherkey]

So all is well...good to hear
Chris