Trouble with point stretch actions

[R.Gerritsen4967]

I'm having some trouble with point stretch actions in a dynamic block. See attachment.

All the vertices of the polyline have point parameters with a stretch action attached to it.

I have also added two linear stretch parameters to change distance A and B.

The trouble I have is with point 5 as indicated in the drawing.

For stretch action A, I need point 5 to move to the left (or right).

For stretch action B, I need point 5 to move down (or up) with a multiplier of 3.

I played around with the stretch action for point 5, but I'm only able to get this to work for stretch A or B, not both at the same time.

Any suggestions?

[Libbya · Accepted solution]

No need for any of the chained points.  Those are just adding complication.  The following screencast shows how to do what you are asking.  At the end of the video I show two different ways to deal with the lower linear parameter depending on how you want the behavior of the limits.  

https://knowledge.autodesk.com/community/screencast/1d81ce4f-4711-4443-968a-da4268a010cc

[j.palmeL29YX]

After analyzing your block I must confess that I don't understand how it should work.
Can you please sketch some examples that show how the block should look like after changing the parameters Distance A and Distance B?

[R.Gerritsen4967]

@Libbya,

Thanks, I'll look into it.

@j.palmeL29YX 

This is a simplified version of the block I'm trying to make.

The block represents a cross section of a steel plate. This plate will be attached (butt-weld) to another plate at position B. The difference between the thicknesses of both plates is a measure for the taper.

So in this block I want to choose the thickness of the plate (distance A) and the thickness of the plate that will be attached to it (distance B).

The taper should always be 1:3.

To be more precise, this plate is a sheerstrake (used in shipbuilding)

For my question on this forum, I omitted the deck plate. The plate that is to be attached at position B would be the shell plate. So for the final version of the block I also need to incorporate the deckplate thickness, and adjust the position of the sheerstrake accordingly.

[j.palmeL29YX]

Something like the attached one? 

[R.Gerritsen4967]

I already made something like this. But I wanted a block without using constraints.

[R.Gerritsen4967 · Accepted solution]

@Libbya,

Thanks, your screencast helped a lot. Had to change a few things though.😁 (added another stretch action for parameter A)

Attached is the version I'm happy with.

[j.palmeL29YX]

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@R.Gerritsen4967 wrote:

I already made something like this. But I wanted a block without using constraints.

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Why don't you tell and show us something like that right at the beginning?
But my answer was not so much about the solution, but rather about what you want to achieve in the end. (And for demonstration I posted a quick and easy to realize example). So far I understand, the two horizontal dimensions shall be able to be changed (in a given range) and the chamfer at the bottom should maintain a constant angle.
My question remains unanswered: What all should the block be able to do? Which values should the user be able to change (for example also the total height?), which constraints should be considered (for example no constraints?), ...?

My next attempt -> see attached block pa-test_1

[EDIT]: Oops, I'm too late .   (" the version I'm happy with")