3D Dynamic block Stretching 3D objects

[SteveD]

I'm using MEP 2014. I've made a dynamic block in 3D of a cable ladder rack. I'd like it to stretch and automagically add rungs at regular intervals. It also has an optional sized rack in visibility, (which hasn't been fully implemented yet, due to the stretch problem). The array of additional rungs works fine, but I can't get the sides to stretch properly. They either don't change or just move along with the rungs. I must be missing something because this should be an easy one.

Thanks for any help.

3DLadderDynamic.dwg

[steven-g]

Forgive me if I'm wrong, but I was under the impression that 3D solids don't stretch, I don't have access to them using LT, I just have a vague recollection of seeing something similar previously, because dynamic blocks use the standard stretch command, I don't think you can do it, you would need to change the content to something that would work with just the normal stretch command.

[ReMark]

3D models can be stretched using their grips. Another way would be to "stretch" them using the Move Faces command.

[SteveD]

These are just extruded polygons. In MEP 2014, when selected they show grips at the apexes and an arrow grip for stretching along the Z axis. When 3Drotated to the correct orientation, they retain this stretching ability outside of the block. Maybe that's the answer-they change inside the block?

 

Thanks for the reply.

LadderSide.dwg

 

Just tried it and they do stretch inside the block editor.

[SteveD]

3D models can be stretched using their grips. Another way would be to "stretch" them using the Move Faces command.

 

So the question becomes, how does the grip stretch differ from the stretch action in a dynamic block? You can also change the length of an extrusion in Properties.

[steven-g]

But does it stretch with the stretch command, not grips or properties, just the plain old stretch command with a selection window.

[SteveD]

No, but neither does a single line. And a line does in the block, but the solid doesn't.

[steven-g]

A line stretches, so does a polyline, a circle doesn't and neither does a region.

[SteveD]

A line stretches, so does a polyline, a circle doesn't and neither does a region.

 

I just tried it and the line didn't stretch, it just moved. Same with the circle. But still, if the 3D solid stretches in and out of the block, why does the stretch action not work? See the original post for the block, check it out and see if anyone can figure out why it doesn't. I'm pretty sure I missed something basic.

[steven-g]

Maybe stretch does work differently, I did try an exploded copy of your block and the solid doesn't stretch (in LT, but then there are no grips either, LT can only view solids). It seems strange that a line won't stretch for you, but the behaviour you mention is the same as that for geometry that won't stretch, the fact that it moves is how regions etc behave during a dynamic stretch action, so I doubt it is a setting.

[Cad64]

Maybe this series of videos will help:

 

I also found this thread. Since your profile says you're using MEP, nestly's post about "clearances" may be of interest: http://www.cadtutor.net/forum/showthread.php?83145-Can-I-make-a-3D-dynamic-Block

[lainezjohn2]

Si se puede lograr que los lados se estiren, pero se hace con thickness en vez de solido 3D.

[Cad64]

Si se puede lograr que los lados se estiren, pero se hace con thickness en vez de solido 3D.

 

This is an English speaking forum. Please post your replies in English.

 

Here is Google's translation:

If you can achieve that the sides are stretched , but is made with thickness instead of solid 3D